OCTOBER’S ECUPSES SEE STARS & PLANETS IMPROVE YOUR ’ OF THE SUN & MOON p .50 IN BROAD DAYLIGHT p. 36 DSLR IMAGES p.72 THE ESSENTIAL GUIDE TO ASTRONOMY
S&T TEST REPORT: A Versatile 100-mm Refractor p. 62 0 0
Comet Buzzes Mars
OCTOBER 2014
How We Discovered the Radio Sun p.30 = • ' • • • . * * ' ' ,* ’ ■ *T-.‘ • ' . 9 Check Out Scopes from Your ' Library p. 66
Visit SkyandTelescope.com Download Our Free SkyWeek App This 4.3° F.o.V. image of Eta Carina (NGC3372) was imaged by Wolfgang Promper using the Tele Vue-NPI 27fli & FLI Proline 1 6803 camera. EASIER IMAGING
Tele Vue and Finger Lakes Instrumentation have tackled the frustration of piecemealling together equipment by engineering o u t eomponents to w o r k in a “turn-key” system. The Tele Vue-NP127fli marries its flat-field, f/5.3 optics witli FLI’s Atlas Focuser, Centerline Filter Wheel, and Proline series cameras. The goal, to create a system that sitnply, rigidly, and squarely locks together and is ready to image. That easy? Wolfgang commented, “re- garding my thoughts it is quite easy, I have used all kinds o f telescopes over the years, different brands and sizes but the Tele Vue-NP127fli was the first one that was perfect out o f the box, without the slightest tweak needed, plus the outstanding sharpness, field correction, and rigidity, to tne it is a perfect instrument.” Testing results have been breathtaking. See fór yourself and learn more ab out the unique features of the NP127fli at Tele Vue.com
‘T e le V u e * 32 Elkay Dr., Chester, New York 10918 (845) 469-4551. televue.com f Visionar y Image: M42, M43 . Santa Barbara Instrument Group SBIG Imager: Tony Hallas 150 Castilian Dr., Suite 101, Santa Barbara, CA 93117 ASTRONOMICAL Camera: SBIG STX-16803 On the cover: OBSERVING OCTOBER M31 is slightly 43 In This Section larger than the Milky Way, but 44 October’s Sky at a Glance it doesn’t best our galaxy in 45 Binocular Highlight There’s more to find online @ every way. By Gary Seronik SkyandTelescope.com 46 Planetary Almanac 47 Northern Hemisphere’s Sky TIPS FOR BEGINNERS FEATURES By Fred Schaaf New to astronomy? Here’s everything you need to jump 20 Battle o f the Titans: 48 Sun, Moon & Planets into the fun. COVER The Milky Way vs. By Fred Schaaf STORY A n d r o m e d a SkyandTelescope.com/letsgo The Milky Way and Andromeda 50 Celestial Calendar By Alan MacRobert galaxies vie for Local Group SKY AT A GLANCE Our popular column highlights supremacy. By Michael Rich 56 Exploring the Moon By Charles Wood celestial delights for the upcom- ing week. Also available as an 30 Discovering the Radio Sun 58 Deep-Sky Wonders app — with sky charts included! The wartime discovery of radio By Sue French SkyandTelescope.com/ataglance emissions from the Sun gave birth to the field of solar radio astronomy. S&T TEST REPORT M O N TH LY SKY PODCAST By J. Kelly Smith & David L. Smith 62 S&T Test Report Listen as we guide you through By Alan Dyer this month’s celestial sights. 36 Stars & Planets SkyandTelescope.com/podcasts ALSO IN THISISSUE in Broad Daylight You don’t need to stop observing 6 Spectrum By Robert Naeye ONLINE STORE just because the Sun is above the Shop our catalog for Moon horizon. By Chris Dalla Piazza 8 Letters globes, sky atlases, and more. shopatsky.com !0 75, 50 & 25 Years Ago 66 Check Out This Telescope! By Roger W. Sinnott An innovative program allows INTERACTIVE SKY CHART newcomers of all ages to borrow 12 News Notes Find out what the sky looks like compact, high-quality reflectors from for your time and place. 42 New Product Showcase public libraries. By John Jardine Goss skychart.SkyandTelescope.com 70 Telescope Workshop 72 Eliminating Band By Gary Seronik ASTROPHOTO GALLERY & Line Noise Enjoy readers’ best images and 76 G allery Here’s a technique that removes upload your own. You can also common artifacts from DSLR and 86 Focal Point submit your images for con- CCD images. By Michael Unsold By Bert Probst sideration for the magazine’s Gallery section. SKY & TELESCOPE (ISSN 0037-6604) is published monthly by Sky & Telescope Media, LLC, 90 Sherman St., Cambridge, MA 02140 SkyandTelescope.com/gallery 3264, U S A . Phone: 800-253-0245 (cu sto m e r service/subscriptions), 888-253-0230 (p ro d uct orders), 617-864-7360 (all o ther calls). Fax: 617-864-6117. Website: SkyandTelescope.com. © 2014 Sky & Telescope Media, LLC. All rights reserved. Periodicals postage paid at Boston, Massachusetts, and at additional mailing offices. Canada Post Publications Mail sales agreement #40029823. Canadian return address: 2744 Edna St., Windsor, ON, Canada N8Y 1V2. Canadian GST Reg. #R128921855. POSTMASTER: Send address changes to Sky Find us on & Telescope, P O Box 420235, Palm Coast, FL 32142-0235. Printed in the U S A . f e j Facebook &Twitter 4 October 2014 sky & telescope LX200 ACF SERIES PROFESSIONAL CLASS TELESCOPES THE BENCHMARK bench*mark Ybench-márkV something that serves as a Advanced Coma-Free (ACF) optical system delivers coma-free, standard by which others may be measured or judged. razor sharp, high-contrast images. Primary Mirror Lock eliminates focus and mirror shift during long Every endeavor has a benchmark from which all others are exposures. judged. From its introduction in 1992, the LX200 has always been a product for which all others compared to. In 2014, Smart Mount™ & Smart Drive™ constantly refines pointing accuracy each time an object is centered and provides Permanent the LX200 ACF still meets this criterion. Superb optical Periodic Error Correction (PPEC). performance coupled with time proven computerized pointing Solid Fork Mount with Heavy Duty 5.75” Gears provide smooth and tracking has made the LX200 ACF series a best-seller in movements with low periodic error for long exposure astrophotography. the high-performance telescope eláss. AutoStar® II controller puts 145,000 objects at your fingertips with the fastest GOTO performance available. OPT Tetescopes B & H Photo Telescopes.com Woodland Hills Adorama Optics Plánét High Point Scientific Astronomics Canada • Khan Scopes 800.483.6287 800.482.8143 800.303.5873 888.427.8766 800.223.2500 800.504.5897 800.266.9590 800.422.7876 800.580.7160 www.optcorp.comwww.bhphotovideo.comwww.telescopes.comwww.telescopes.netwww.adorama.comwww.opticsplanet.comwww.highpointscientific.comwww.astronomics.comwww.khanscope.com fjMEADE INSTRUM ENTS www.meade.com Róbert Naeye Foundedin 1941 by Charles A. Federer, Jr. Spectrum and Helen Spence Federer SKY The Essential Guide & TELESCOPE to Astronomy EDITORIAL Editor in Chief Robert Naeye Senior Editor Alan M. MacRobert Associate Editor Tony Flanders Imaging Editor Sean Walker Assistant Editor Camille M. Carlisle Passing the Torch Web Editor Monica Young Editor Emeritus Richard Tresch Fienberg Senior Contributing Editors J. Kelly Beatty, Roger W. Sinnott W h e n i a s s u m e d the mantle of S&T editor in chief in June 2008, Contributing Editors Jim Bell, Trudy Bell, John E. Bortle, Greg Bryant, in the back of my mind I figured my run would last about 5 to 7 years Paul Deans, Thomas A. Dobbins, David W. Dunham, Alan Dyer, Tom Field, Ted Forte, Sue French, Steve Gottlieb, David Grinspoon, Paul J. before I ’d burn out and turn to other things. I had it just about right. As Heafner, Ken Hewitt-White, Johnny Horne, E. C. Krupp, Emily Lakdawalla, Jonathan McDowell, Rod Mollise, Donald W. Olson, Joe Rao, Dean I write these words in late July, a little more than 6 years after my start, I Regas, Fred Schaaf, Govert Schilling, Gary Seronik, William Sheehan, have informed my colleagues of my intention to move on, and our parent Mike Simmons, Alan Whitman, Charles A. Wood, Robert Zimmerman company, F+W, is now looking for a new person to grab the torch and Contributing Photographers P. K. Chen, Akira Fujii, Robert Gendler, Babak Tafreshi carry it forward. I ’ll stay on until a replacement is on board, and I look ART & DESIGN forward to contributing in various ways after my departure. Design Director Patrícia Gillis-Coppola Illustration Director Gregg Dinderman I’ll be leaving S&T with a heavy heart, but with my head held high. Illustrator Leah Tiscione I’ve enjoyed many wonderful moments during this 6-year tenure: PUBLISHING AND MARKETING meeting countless S&T readers at star parties and trade shows, putting AdvertisingSales Director Peter D. Hardy, Jr. Advertising Services Manager Lester J. Stockman out a magazine and website that people love, and working with a IT Manager Denise Donnarumma Consumer Marketing Joseph Izzo dedicated bunch of people. I can’t thank my fellow editors and art F+W, A CONTENT + ECOMMERCE COMPANY colleagues enough for their tremendous effort and support. As senior Chairman & CEO David Nussbaum editor Alan MacRobert likes to say, “I have one of the few good jobs left CFO & COO James Ogle President David Blansfield in America. I get to work in a no-jerk* zone.” (*Not Alan’s original word.) Chief Digital Officer Chad Phelps VP / E-Commerce Lucas Hilbert I can’t thank all of our contributors enough. I thank Stephen Kent and Senior VP/ Operations Phil Graham Joel Toner of New Track Media for giving me this opportunity. And most VP Communications Stacie Berger Director o f Magazine Marketing & Fulfillment Mark Fleetwood of all, I thank all of you loyal readers for your long-standing support! Editorial Correspondence: Sky & Telescope, 90 Sherman St., Cam Sometimes people w ill ask me at astronomy events how S&T is bridge, M A 02140-3264, U S A . Ph one: 617-864-7360. Fax: 617-864-6117. E-mail: [email protected]. Website: SkyandTelescope. doing, with an expression of concern given the knowledge that print com. Unsolicited proposals, manuscripts, photographs, and electronic publishing is suffering economic hard times. I take comfort knowing images are welcome, but a stamped, self-addressed envelope must be provided to guarantee their return; see our guidelines for contributors at that I leave with S&T standing on terra firma. And based on reader SkyandTelescope.com. surveys and conversations with subscribers, I sleep soundly feeling that Advertising Information: Peter D. Hardy, Jr., 617-864-7360, ext. 2133. Fax: 617-864-6117. E-mail: p e terh @ S kyan d T elesco p e .co m my colleagues and I have maintained S&T’s hard-earned reputation for Web: SkyandTelescope.com/advertising accuracy, quality, and integrity despite challenging circumstances. Customer Service: Magazine customer service and change-of-address Still, a lot of pressures and stresses have built up over the years, and I notices: [email protected] Phone toll free U.S. and Canada: 800-253-0245. sense a deep need to take some time off and try my hand at freelancing. O u tsid e th e U .S . and Canada: 386-597-4387. Product customer service: [email protected] Also, the media world is rapidly evolving, yet I’ll probably always remain Ph on e toll free: 888-253-0230. a traditional print journalist at heart. I just don’t think the complexity Subscription Rates: U.S. and possessions: $42.95 per year (12 issues); and beauty of astronomy can be adequately conveyed in a 140-character Canada: $49.95 (including GST); all other countries: $61.95, by expedited delivery. All prices are in U.S. dollars. tweet, and I worry that the future belongs to media outlets who shout Newsstand and Retail Distribution: Curtis Circulation Co., loudest, not to those who take the time and effort to get the story right. 730 River Rd., New Milford, NJ 07646-3048, USA. Phone: 201-634-7400. Before closing, I wanted to congratulate a contributing editor who No part of this publication may be reproduced by any mechanical, photographic, or electronic process, nor may it be stored in a retrieval system, transmitted, or otherwise always gets the story right: Dutch science journalist Govert Schilling. copied (with the exception of one-time, noncommercial, personal use) without written permission from the publisher. For permission to make multiple photocopies of the Govert has won the prestigious 2014 David N. Schramm Award for same page or pages, contact the Copyright Clearance Center, 222 Rosewood Dr., Dan- vers, MA 01923, USA. Phone: 978-750-8400. Fax: 978-750-4470 Web: www.copyright. High-Energy Astrophysics Science Journalism from the American com. Specify ISSN 0037-6604. Astronomical Society for his article “The Frozen Neutrino Catcher” in The following are registered trademarks of Sky & Telescope Media, LLC: Sky & Telescopeand logo, Sky and Telescope,The Essential Guide to Astronomy, the January 2014 S&T. Skyline, Sky Publications, SkyandTelescope.com, SkyWatch, Scanning the Skies, Night Sky SkyWeek, and ESSCO. Editor in Chief \;±WÁÁ W\ » Nrtn *- 6 October 2014 sky & telescope ©2014 Sky-Watcher USA. Speciffiations subject to change without notice. 20-14*014. W e've m e n tio n e d this b e fo re , but it bears re p e a tin g : We w o n 't be mad if you decide to pay more and get le s s , ju s t ve ry , very d is a p p o in te d . , dollars more. more. dollars , For information on all of our products and services, or to find an authorized Sky-Watcher USA dealer near you, just visit visit just you, near USA dealer Sky-Watcher authorized an find to or services, and products our of all on information For •• ■ • ’ ’ • ’ * ’ * , • ^ ■ . • • . v • All Sky-Watcher USA Esprit refractors come with with come refractors USA Esprit Sky-Watcher All corrector field 2-element included The imaging of kind the With Sky-Watcher USA’s award-winning Esprit triplet APO refractors, you get you refractors, EspritAPO triplet USA’s award-winning Sky-Watcher With otn huad f ] \ v , . x color false glass, Schott and FPL-53 with made design, lens objective air- spaced three-element their With of thousands costing USA's elite Sky-Watcher mind, in astrophotographer get out under the stars. the under out get needto you Everything case. hard foam-lined and plate dovetail rings, mounting adapter, camera reflectivity 99% finderscope, angle right 50 x 9 a entire the across field flat a guarantees WHY PAY MORE TOLESS? GET PAYMORE WHY te usdntgv o. ; * • * the accessories ; the of all with you., give don’t price...along guys the half other at performance the all scmltl lmntd ilig L ^ j | ^ sharpness. and * contrast exceptional yielding eliminated, completely is telescopes from expect would one performance deliver refractors triplet Esprit -nhSa ignl -lmn il ltee, ‘ flattener, field 2-element diagonal, Star 2-inch shift. image zero with focuser smooth, a rock-solid provides system focusing rack-and-pinion helical exclusive Sky-Watcher The plane. imaging Designed with the discerning discerning the with Designed . * ■ . • • „ « % • ' •. • ' * • • % • « „ . *• ' . • •. • '• . • ' . ' 4• Sky-Watcher USAwith Sky-Watcher come Esprits everything see here. you everything L J . . ^ r ^ / . • \V \ . f :'- í Don't forget to follow us on Facebook and Twitter for exclusive offers! exclusive for Twitter and Facebook on us follow to forget Don't k-ace USA Sky-Watcher * ♦ , • ♦i • * , k Scope: Sky-Watcher Esprit 150mm EDT f/7150mm Esprit Sky-Watcher Scope: Ballauer Imager:Jay . d e z a m a e B Cameras included not and mount 150mm Esprit 120mm Esprit 100mm Esprit srt8mm Esprit80m www.skywatcherusa.com ...... $6,39i $3,199 $2,499 $1,649 . Letters A Sky Full o f Friends Paul Greenewich’s essay “Soothing Stars” (S&T: M ay 2014, p. 86) resonates with me. W hile I probably didn’t reach the level of an “official” diagnosis for anything, as a child I also often felt insecure and lonely. Like Greenewich, I found the sky to be “a haven of peace, simplicity, and order.” Now at 57 years old, I ’ve outgrown my childhood anxieties and am even told that I am good with people. Yet, I still find the sky to be a way to recharge. Every night I go out at least once to look at the sky. If conditions are good and my schedule allows, I get out my telescope or binoculars. Even when it’s cloudy I go out and try to catch a glimpse of one of my “old friends” through a gap. A few weeks ago I stepped out later than usual and said out loud, “Oh, hello Mars.” It was my first sighting this apparition, and it really felt like I was greeting an old friend that I hadn’t seen in over a year. I have carried this into the daytime as well, with an equatorial sundial in my wife’s flower garden. Besides tracking the LEAH TISCIONE S&T: daily progression of the Sun’s shadow, the sundial also easily shows the progression speculated to have had) Asperger syn- explanation that the illusion can manifest of the seasons as the Sun’s declination drome includes Albert Einstein, Isaac itself both visually and pictorially, the changes. I take tim e to study it each day. Asimov, and Carl Sagan.” I’m afraid I Terby White Spot still appears quite promi- These sim ple observations o f the clock- must refute the last example. Carl and I nent in the Saturn image in Dobbins’s arti- work of the sky always bring a simple, were classmates at the University of Chi cle. For those of us who can’t reconcile our childlike joy to me. cago, where we both earned our under- eye with Dobbins’s explanation, here’s an Craig MacDougal graduate and graduate degrees, and I was easy way to demonstrate the false nature of Tampa, Florida the best man at his marriage to Lynn neé the Terby White Spot on this image. Alexander. Carl was warm, ambitious, Obtain a white 3x5 index card (or a Before I retired from Case Western charismatic, and enthusiastic about many sheet of white paper) and align the left Reserve University in 1997, I spent many things. He was influential in my choosing edge of the white paper with the right wonderful nighttime hours observing astronomy as a career, and I treasure the edge of the spot. Once aligned, the Terby stars and galaxies at observatories in time we spent together. From what I know White Spot w ill disappear as if by magic. Arizona, California, Ohio, Texas, and of the manifestations of Asperger syn- This is because the white color of the Chile. Those were the days when astrono- drome through reading and contact with paper removes the contrast between the mers were on the observing platform, not persons diagnosed to have it, Carl showed edge of the illuminated portion of the ring in a room watching computers run the not a trace. and the shadowed portion of the ring. telescope, so we actually saw the sky and Peter Pesch Now, slowly slide the index card to the stars. I enjoyed these long hours, usually Beachwood, Ohio right. As soon as you uncover a sufficient alone, at the scope. Thus I can relate with amount of black between the ring and the Greenewich’s description of the ordered, Out, Darn Spot paper, the Terby White Spot w ill magically peaceful night sky. I enjoyed Thomas Dobbins’s column about reappear. It is truly an illusion. However, he also wrote that the “long the illusionary nature of the Terby White Frank Ridolfo list of high achievers who have (or are Spot (S&T: M ay 2014, p. 54). Despite the Bloomfield, Connecticut 8 October 2014 sky & telescope CORONADO THE ULTIMATE IN SOLAR OBSERVATION SolarMaxll 90 Shown Double Stacked Personal Solar Telescope (PST) Prices starting at $3,599 Shown Double Stacked Shown on optional DSM GOTO mount Prices starting at $699 SolarMaxll 60 Shown Double Stacked Prices starting at $1,299 THE SUN ALWAYS RISES Unless you live at our extreme northern or Southern latitudes, you Only the Meade’s Coronado SolarMaxll has the exclusive, can count on this daily occurrence and, unless it is cloudy, you patented, RichView™ system that delivers quick and easy tuning can also count on observing our closest star, the Sun. The Sun’s for highest contrast, yielding detailed views of active regions, weather is always changing; calm one moment, a frenetic mass flairs, filaments and other surface features or, just as quickly, of turbulence the next. Don’t miss an opportunity to witness this retune for prominences on the solar limb. With apertures of through a Coronado SolarMax™ll telescope. 90mm, 60mm and 40mm there is a Coronado solar telescope that will meet everyone’s needs. Meade has you covered. Letters Quasars with a multiple interferograms together in order Backyard Radio Scope to achieve a signal-to-noise ratio adequate Write to Letters to the Editor, Sky & Telescope, The March 2014 issue included an article for detection. 90 Sherman St., Cambridge, mA 02140-3264, on an amateur program of observing qua- The quasar 3C 273 lies at a redshift of or send e-mail to [email protected]. Please limit your comments to 250 words. sars with optical telescopes (“New Jersey 0.16 (light travel time of 2 billion years), Quasar Quest,” p. 34). Although I have whereas 3C 298 has a redshift o f 1.44 Published letters may be edited for clarity and seen the brightest quasar 3C 273 in my (light travel time of 9.3 billion years). It is brevity. Due to the volume of mail, not all letters can receive personal responses. 8-inch SCT, my own quasar observation mind-boggling to me to realize that the program consists of detecting radio-loud energy from these quasars has been travel- quasars with an amateur radio telescope. ing through space at the speed of light My backyard radio telescope consists for billions of years before arriving at my The observatory originally belonged o f two 10-foot T V R O dishes operating backyard. to Frank Evans Seagrave (1860-1934), a as a phase-switched interferometer in a Jim Abshier fam ous Providence astronomer. The soci- 4-MHz frequency band near 1420 MHz. Via e-mail ety has served as the observatory’s stew- The output of my radio telescope is an ard since 1936. It includes four telescopes, interferogram record stored in a personal Invitation to Seagrave Centennial among them the refurbished 8-inch Alvan computer. So far, I have detected 11 qua- Skyscrapers, Inc., the amateur astronomi- Clark refractor for which Seagrave built sars, including the loudest one, 3C 273, cal society of Rhode Island, is proud to the observatory. Interested readers can with a flux density of 46 janskys, and announce the celebration of the 100th explore the rich history and find out more 3C 298, with a flux density of 6 janskys. anniversary of Seagrave Memorial about the event at the society’s website (The jansky is a unit of flux density equal Observatory in North Scituate during our www.theskyscrapers.org. to 10-26 watts per square meter per hertz). annual AstroAssembly 2014 convention David A. Huestis For the fainter quasars, I have to average (Septem ber 26-27). North Scituate, Rhode Island 75, 50 & 25 Years Ago Roger W. Sinnott October 1964 (^■TFLESCOPE SePtember- °ctober Zgrablic (University of Zagreb, Croatia) reported 1939 Sounds from Meteors the instrumental detection of short, low-frequency Sad Centennial “ On “There has been con- sounds from two Leonid fireballs they had August 19, 1839, the sistently, throughout observed from Mongolia. Pulkov[o] Observatory historical times, a minor- was officially dedicated ity o f fireball observers October 1989 in the presence of the who claim to have heard Pulkovo Purge “Accord- Czar o f all the Russias. sounds simultaneously ing to [losif S.] Shklovskii, suminia ■ v.n; ■ iktí^hT The importance of this with seeing a meteor's ‘Pulkovo Observatory event. . . still looms light. These have been had long been a sore large[:] The double-star work and star-position described in many different languages as hissing, spot in the eyes of the catalogues of the Struves, Belopolsky's spec- swishing, whizzing, whirring, buzzing, and crack- Leningrad authorities.' troscopic contributions, and many others are ling. Since the distance between the observer The astronomers there preserved in the literature. . . . and the fireball is too large . . . for ordinary sound were perceived as too “Other countries of the world became jeal- transmission, these noises have been called proud and independent. ous of Russia's scientific fame and sought to ‘anomalous' because they appear to be transmit- Their frequent travels to foreign observatories emulate and surpass it. In France [astronomer ted at the speed of light. . . . and conferences resulted in many ‘suspicious' Francois] Arago pointed out that the accom- “One of the few recent meteors that engen- contacts in the United States and Europe. . . . plishments in the land of the free were being dered anomalous sound reports was the ‘Mad “Overall some 25 to 30 astronomers — 10 surpassed by those in the ‘land of the serfs.' Ann' fireball of September 1, 1962, seen in West to 15 percent of the Soviet Union's total and John Quincy Adams impassionately echoed the Virginia, Virginia, and Ohio. [An] observer near nearly 50 percent of those in Leningrad — were phrase in this country, urging the establishment Covington stated in an interview that a hissing arrested between March, 1936, and July, 1937. of a national observatory." noise made him look up and see the fireball." Almost all of them came from the Pulkovo or Rumors o f dire events at Pulkovo under Soviet Mary Romig and Donald Lamar (RAND Tashkent observatories or from the Astronomi- rule might have inspired this editorial tribute. Corporation) noted that “electrophonic hearing" cal Institute. . . . [M]ost astronomers taken into Decades would pass before full details emerged of might be involved, in which a sensitive observer custody in 1936 and 1937 never returned." the ghastly fates of astronomers during the Great picks up radio-frequency radiation (perhaps Robert A. McCutcheon’s landmark feature Purges underJoseph Stalin, which lasted from because the electromagnetic waves cause nearby detailed for the first time the horrors that had 1936 to 1938 (see the 1989 quotation). objects to vibrate). In 2002 a team led by Goran befallen many astronomers and their families. 10 October 2014 sky & telescope Introducing the NEW. ÍEQ45 Pro" iWptron Features • Ideál for visual and astrophotography • Payload: 45 Ibs | Mount weight: 25 Ibs • Updated and more advanced control electronics • Higher gear ratio for smoother tracking • ST-4 autoguiding port capable of reverse guiding with auto-protection • Permanent periodic error correction (PEC ) #8000E ÍEQ45 Pro | $1848 • Built-in 32-channel G P S #8000E-AZ ÍEQ45 Pro AZ j $1948 • Hand controller with Advanced GOTONOVA® GoTo Technology and heating mechanism • Low working temperature: -20 degrees C • RS232 port for mount firmware upgrade and A SC O M control • Stepper motors • Resolution: 0.09 arc second • Spring loaded dovetail saddle for both Vixen and Losmandy-type mounting plates • 2 inch heavy-duty stainless steel tripod legs (16.5 Ibs) • Die-cast metál tripod spreader with accessory tray • Optional 42-inch (#8033) or 48-inch (#8030) pier available. •AccuAlign™ polar scope with dark-field illumination • Available in EQ-only or dual EQ/AZ model • Comes standard with: 2 x 5kg counterweight AC adaptor & 12V DC cár plug adaptor RS232-RJ9 and RS232 cables, stainless steel counterweight shaft www.iOptron.com f a i m I I I * Adorama 1.800.223.2500 www.adorama.com Astronomics 1.800.422.7876 www.astronomics.com Featured Dealers: Hands On Optics 1.866.726.7371 www.handsonoptics.com Visít wwwiOptron com High Point Scientific 1.800.266.9590 www.highpointscientific.com for a complete iist of dealers OPT 1.800.483.6287 www.opttelescopes.com Telescopes.com 1.800.303.5873 www.telescopes.com Woodland Hills Telescopes 1.888.427.8766 www.telescopes.net Ontario Telescope (Canada) 1.905.487.6363 www.ontariotelescope.com To get astronomy news as it breaks, -3«í- News Notes visit skypub.com/newsblog. COSMOLOGY I Shadow of a Supervoid ESA / PLANCK COLLABORATION Cosmologists might have discovered the So cosmologists have sought alternate The Cold Spot (circled) in the cosmic microwave source of a mysterious cold spot in the explanations. One of these is a supervoid, a background appears in observations from both cosmic microwave background (CMB): an large, comparatively empty region between the WMAP and Planck spacecraft. It is one of enormous supervoid in the universe’s web galaxy clusters in the universe’s large-scale several anomalies (also shown in the Planck of galaxies. cosmic web. As light travels through the data above is the “ hemispheric asymmetry” ). Generally, the temperature variations gravitational hills and valleys created in the in the CMB grew from primordial density fabric of spacetime by cosmic structures, distant, early universe. variations that inflation stretched to the photons lose or gain energy — lose if Now István Szapudi (University of gigantic scales. But during its nine-year they climb the hill of a void, gain if they Hawaii) and colleagues have analyzed stint mapping the CMB, NASA’s Wilkin- descend into a cluster’s valley. But the galaxies in the WISE-2MASS catalog to son Microwave Anisotropy Probe (W M AP) expansion of space flattens this gravita- discover a vast supervoid that might be revealed several anomalies that inflation is tional landscape. Photons w ill climb down responsible for the Cold Spot. unlikely to have created. One of the most a hill or out of a valley that’s smaller than Szapudi’s team combined data from the infamous is the so-called Cold Spot, a it was at the outset, ending up with a net WISE-2MASS catalog and Pan-STARRSl, large region spanning 10° in Eridanus that loss or gain of energy in what’s called the a robotic telescope that images the full sky is about four times cooler than the average Integrated Sachs-Wolfe effect. once per week. They mapped relatively CMB fluctuation. Cosmologists had therefore suggested nearby galaxies lying within the Cold It’s statistically unlikely that the Cold that a supervoid spanning hundreds of Spot’s boundaries on the sky and found Spot originates from primordial density millions of light-years could cause the that the density of galaxies existing 11.1 variations. And if density variations are Cold Spot: the energy lost would effectively billion years after the Big Bang decreased to blame, then the Cold Spot’s existence create a cool fingerprint on the CM B. But near the center of the Cold Spot. could pose a challenge to the favored previous void searches had come up empty The supervoid appears to be roughly model of inflation. — in part because they had searched the continued on page 14 12 October 2014 sky & telescope LIGHTBRIDGE TRUSS-TUBE DOBSONIANS A BIG TELESCOPE THAT GOES ANYWHERE HIGH POWER PORTABILITY It's not just a big telescope. It’s a big telescope that goes High-Quality Diffraction Limited Optics ensure that the views anywhere. LightBridge™ truss-tube dobsonians from through your telescope are detailed, cnsp and full of contrast. Meade take down and set up quickly. So you can take 2" Crayford-Style Machined Aluminum Focuser provides smooth precise focusing. A unique focus tension knob and focus lock design one of these massive windows on the universe out to your gives you complete control over focus. favorité dark sky location with ease. Advanced Four-Reticle Red Dót Viewfinder with varying brightness Controls allow it to adjust to your observing needs. LightBridge dobsonians give you high quality Meade 26mm Wide Angié 2" Eyepiece with a stunningly wide 70° optics, prémium components and ultra portability — all apparent field of view. for about the same price as an ordinary tube dob. So get Built-ln Primary Mirror Cooling Fan brings the telescope into a LightBridge truss-tube dobsonian. And prepare to cross thermal equilibrium quickly and efficiently with the battery powered the universe. cooling fan. OPT Telescopes B & H Photo Telescopes.com Woodland Hills Adorama Optics Planet High Point Scientific Astronomics Canada • Khan Scopes 800.483.6287 800.482.8143 800.303.5873 888.427.8766 800.223.2500 800.504.5897 800.266.9590 800.422.7876 800.580.7160 www.optcorp.comwww.bhphotovideo.comwww.telescopes.comwww.telescopes.netwww.adorama.com www.opticsplanet.comwww.highpointscientific.comwww.astronomics.comwww.khanscope.com ilM EADE INSTRUMENTS www.meade.com OG News Notes continued from page 12 spherical, though its internal structure EXOPLANETS I Debated World Doesn’t Exist might be more complex, containing A new analysis of stellar activity for the The new work by Paul Robertson smaller voids and filaments, the team M dwarf star Gliese 581 confirms that its (Penn State) and colleagues makes clear reported earlier this year at the Moriond planet d is likely a ghost in the data. that d needs the boot, too. The team Cosmology Conference in Italy. The G J 581 has been a poster child for took another look at the H ARPS spectra, researchers estimate that the supervoid, multiplanet systems for several years. In focusing on hints of stellar activity from possibly the largest yet discovered, spans 2005 a Geneva-led team using the E S O ’s hydrogen-alpha emission. This emission about 900 m illion light-years. According H ARPS spectrograph discovered the first comes from hydrogen atoms being hit by to Mark Neyrinck (Johns Hopkins Uni planet, b; in 2007 they reported c and d, particles accelerated along magnetic field versity), this is “the clearest evidence yet and in 2009 e. A ll these planets have orbits lines in the star’s atmosphere. Stronger that there is a supervoid that substantially smaller than Mercury’s, but around a star magnetic fields mean more acceleration, affects the cosmic microwave background.” 30% the size of the Sun and 60% as hot. which means more emission. But there are still a few unanswered A second team used a combination of But stronger magnetic fields also mean questions. One is the strength of a observations from HARPS and Keck’s more stellar activity, which can create supervoid’s impact on the CMB: the initial H IR E S spectrograph to suggest the pres- shifts in starlight that look much like calculation for the new ly spotted super- ence of two more planets, f and g, but the radial-velocity wobbles induced by an void does not fully account for the CMB these were quickly questioned and have orbiting planet. temperature drop of the Cold Spot. basically fallen away. Robertson’s team found that during Another question is how prevalent Some astronomers have also ques- times of higher magnetic activity, the supervoids are. If a larger sky survey tioned whether d actually exists, notably strength of d’s signal went up. When the reveals that they are fairly common, then Roman Baluev (Pulkovo Observatory, Rus- star was less active, the signal weakened. a single supervoid would be a less likely sia), who in 2012 did a careful analysis of They also found that the star’s rota- explanation for the anomaly. “W ith a larger noise in the observations and raised a red tional period is twice as long as planet d’s sample, it would be clearer that this super- flag. But analyses of stellar activity turned orbital period of 66 Earth days. That sug- void is the only thing on the sky capable of up no big starspots that could masquerade gests d’s signal is from the star itself, the making a big imprint like the Cold Spot,” as a planet, and d stayed in the catalogs team reported online July 3rd in Science. explains Neyrinck. “This would make the — and on the list of potentially habitable Taken together, the observations sup- issue basically indisputable.” planets, because much of its predicted port only one likely conclusion. “I think ■ MARIA TEMMING orbit fell in G J 581’s habitable zone. the evidence shown by Robertson et al. is strong enough to remove G J 581d from the list of exoplanets,” says Xavier Bonfils (Grenoble Observatory, France), who co- BLACK HOLES I Gas Streamer Eclipses AGN authored the original discovery paper. Observations of the Seyfert galaxy NGC tra’s team estimates that the outflow has Although Bonfils and his colleagues 5548 show a new gas streamer flowing from lasted between 2% and 6 years. searched for starspots, G J 581 appeared to be starspot-free during their observa near its supermassive black hole, astrono As matter spirals into a black hole, it tions. But Robertson’s team found that, mers report in the July 4th Science. Many emits ultraviolet radiation that can excite although no big, dark blemishes showed active galactic nuclei (AGN) spew gaseous surrounding gas and induce powerful up on the star’s surface, the H-alpha outflows, but NGC 5548 is the first whose outward-bound winds. But if the gas is too emission clearly indicates that the star streamer has moved into our line of sight. saturated by X-ray radiation, then it gets had magnetically active regions at the Previous high-resolution X-ray and ultra- "cooked” and loses its ability to absorb the time. It’s these regions that mucked up violet observations showed a persistent ultraviolet radiation that launches it away. the spectra. outflow of gas from this AGN, which is The new streamer in NGC 5548 shields sur Stellar activity is a known problem expected for these objects. But while moni rounding gas from the AGN’s X-ray radia with searches for exoplanets, particu- toring NGC 5548 last June, Jelle Kaastra tion, allowing the powerful winds seen to larly around M dwarfs. Given the signal (Netherlands Institute for Space Research) come from the AGN. strengths involved, Bonfils thinks that and colleagues detected a new, clumpy Although the winds billowing from NGC only a few reported exoplanets at most stream of ionized gas that was blocking 5548 are not strong enough to significantly might prove to be from active regions like 90% of the AGN’s X-ray emission. This gas affect the galaxy’s evolution, this study those Robertson’s team found. Accounting streamer probably originates near the accre- improves our understanding of how shield- for these shifts in starlight w ill prove espe- tion disk, mere light-days from the central ing mechanisms could influence galaxies cially important for low-mass planets in black hole, and flows outward at 1,000 kilo- with more powerful AGNs. moderate to long orbital periods, he adds. meters per second (2 million mph). Kaas- ■ MARIA TEMMING ■ CAMILLE M. CARLISLE 14 October 2014 sky & telescope ”• ,*".J NGC 6514 (M20) The Trifid Nebula courtesy of Jay GaBany: RCOS 20- inch, Apogee Alta U16M, Astrodon E-Series filters; 360 minutes Luminance, 120 minutes Red, 120 minutes Green, 120 minutes Blue (All 1X1) Apogee has been manufacturing and supplying cooled CCD cameras to astronomers around the world since it was founded in 1993. Apogee Apogee’s Alta camera series is designed to offer a broad range of sensor options attractive to the Astronomy community. The new IMAGING SYSTEMS Aspen and Ascent cameras further extends the Apogee portfolio providing higher performance and better affordability. www.ccd.com In 2013 Apogee was acquired by Andor Technology, adding further expertise in camera development, manufacturing and customer support. ANDOR an Oxford Instruments company News Notes GALAXIES I Mysterious X-rays Hint at Dark Matter Two teams o f astronomers have dis- at 3.12 keV that is 30 times stronger than covered an inexplicable spike in X-ray observed. emission from galaxy clusters. Using Even before the Astrophysical Journal independent methods and observations, published Bulbul’s results in its June 10th Esra Bulbul (Harvard-Smithsonian Center issue, dozens of papers flooded the arXiv for Astrophysics and NASA Goddard) and online preprint repository, serving up Alexey Boyarsky (Leiden University, The various theories to explain the mysteri- Netherlands) and their teams have found ous X-ray spectral line. Nearly all of them a previously undiscovered spectral line in turned to dark matter. long-exposure observations of more than Why? Galaxy clusters are the largest 70 clusters. gravitationally bound structures in the Galaxy clusters are vast repositories of universe. That means they’re one of the hot, ionized gas. Exploding stars, which best places to search for dark matter, forge heavy elements, eject the gas from which reveals itself by its gravitational the galaxies. Over billions of years, this interactions with ordinary matter. This X-ray composite shows the core of heavy-element-contaminated plasma col- The proposed dark matter explanations the Perseus galaxy cluster. A mysterious lects between galaxies and glows brightly range from annihilating sterile neutrinos X-ray signal from this cluster and 72 oth in X-rays. ers has perplexed astronomers. to what’s called eXciting Dark Matter Bulbul’s team collected and combined (XDM). In the XDM model, dark matter archival XMM-Newton observations of 73 has its own forces that act only on it and galaxy clusters, ranging from the brightest detection with a different instrument. not on ordinary matter. The interaction of — the nearby Perseus Cluster — to fainter And Boyarsky’s team sees the same bump XD M particles expected in hot, high-den- and faraway clusters. Their careful analysis, at the same energy in a separate, not-yet- sity environments might explain why the which smeared out instrumental noise, published study of the Andromeda Galaxy still-forming Virgo Cluster doesn’t show revealed a statistically significant, if some- and the Perseus Cluster. evidence of the 3.55-keV bump: dark mat what ratty-looking, bump with an energy of Yet there shouldn’t be a bump at that ter hasn’t had time to settle to its center. roughly 3,550 electron volts (3.55 keV). The energy, according to known plasm a phys- “ W e know that the dark m atter expla- bump remains even when they divide the ics. The most likely “normal” explanation, nation is a long shot, but the payoff would stacked spectrum from the 73 clusters into a super-strong line from the element be huge if we’re right,” Bulbul says. “ So sub-samples and redo their measurements. argon, is “physically impossible,” Bulbul we’re going to keep testing this interpreta- The team checked archival observa- says. To produce the 3.55 keV bump, tion and see where it takes us.” tions from Chandra, confirming the same argon would also have to produce a line ■ Im o n ic a y o u n g IN BRIEF Black Hole Triplet Found. On July 3rd in 450 light-years apart and lie 24,000 light-years candidates: 2009 BD, 2013 EC20, and 2011 MD. Nature, astronomers reported that the double from the third. Twists found in one black Each candidate is less than about 10 meters AGN SDSS J1502+1115 is actually a highly hole’s jet confirm that looking for warped jets across and spins less than once every 2 min compact triple active galactic nucleus (AGN). might reveal binaries that astronomers can’t utes. The other three candidates are for Option Such systems have been predicted to form otherwise resolve. B, which involves retrieving a boulder from in galactic mergers, but only a few have been ■ MARIA TEMMING a larger asteroid. These are 25143 Itokawa, observed, so astronomers assumed multi- 2008 EV5, and 101955 Bennu, the target of AGN cores were rare. Using very long baseline NASA Amasses Asteroid Targets. As of late the upcoming OSIRIS-Rex mission. Ongo- interferometry, Roger Deane (University of June, NASA had found six “valid candidates” ing searches might find an additional two to Cape Town, South Africa) and colleagues that meet rendezvous criteria for its mission three candidates per year until 2018, when the found their black hole trio after searching only to find, retrieve, and explore an asteroid (S&T: agency will have to decide both which option six galaxies, indicating that these systems July 2013, p. 12). For Option A, which aims to they’re going with and which asteroid they’ll might be more common than previously bag a small asteroid and bring it back to lunar target for a projected 2019 launch. thought. The inner two black holes are about retrograde orbit, mission planners have three ■ MONICA YOUNG 16 October 2014 SKY & TELESCOPE LX850™ WITH STARLOCK™ THE SMART CHOICE FOR ASTRO-IMAGING Meade’s revolutionary LX850 system draws upon 40 plus years of experience and inpovation. Precision machining, finishing, assembly combined with StarLock’s fully integrated, full-time autoguiding system makes this platform the new standard in astrophotographic and visual performance. + FASTER, SHARPER OPTICAL SYSTEM ■ Fást f/8 ACF™ optical system with high-contrast baffling that assures crisp, pinpoint stars to the very edge of the field. ■ Internál Crayford-style, zero image-shift focusing system with two-speed, 7:1 control. PRECISION MACHINED, SOLID GERMAN EQUATORIAL MOUNT Made from machined aluminum and stainless Steel with large bearing surfaces and roller bearings in both axes for an extremely solid and stable platform. Precision machined 5.8 inch main gears with 225 teeth in both R.A. and DEC. with .68 inch polished bronze worms for precise movements and tracking. ■ Internál cabling to prevent snags and tangles. ■ 1.75 inch diameter threaded stainless Steel counterweight shaft for easy and safe adjustments to telescope balance. + STARLOCK — FULL-TIME AUTOMATIC GUIDING Uses an 80mm f/5 optic and a super wide-angle lens in “ The LX850 Astro-lmaging System is a quantum leap forward. a two camera system. It has done for deep-sky astrophotography what Go To telescopes did for observing Provides computer-assisted drift alignment for refining polar alignment. ” - Dennis di Cicco Finds and centers targets and then automatically locks onto a field star as faint as 11th magnitude for guiding. LX850 Mount Only — 55,999 ■ Automatically programs periodic error correction and then corrects for other errors down to virtually zero. W ith 10” f/8 ACF — $7,999 W ith 12” f/8 ACF — $8,999 W ith 14” f/8 ACF — $9,999 For more detailed information about the LX850 go to: www.meade.com/lx850 With 130mm APÓ — $8,998 OPT Telescopes B & H Photo Telescopes.com Woodland Hills Adorama Optics Planet High Point Scientific Astronomics Canada • Khan Scopes 800.483.6287 800.482.8143 800.303.5873 888.427.8766 800.223.2500 800.504.5897 800.266.9590 800.422.7876 800.580.7160 www.optcorp.comwww.bhphotovideo.comwww.telescopes.comwww.telescopes.netwww.adorama.comwww.opticsplanet.comwww.highpointscientific.comwww.astronomics.comwww.khanscope.com (Jg) MEADE INSTRUM ENTS www.meade.com O 2014 Meade Instruments Corp. All rights reserved. Specifications and príces subject to change without notice. Patents pending. 30-13097 News Notes OBIT I Bill Bradfield, Comet Hunter Extraordinaire (1927-2014) William A. Bradfield, the mild-mannered for portrait photography. A war-surplus comet hunter of South Australia, died on Erfle eyepiece provided 26x. W ith a 2-foot June 9, 2014, at age 86. His remarkable lever arm the instrument could be raised tally of 18 comets, each discovered visu- or lowered to let the observer stand com- ally and credited to him alone, puts him fortably at the eyepiece. among the most prolific and elite comet Although none of his comets gave us discoverers of all time. the jaw-dropping spectacle of a Comet Yet Bradfield didn’t even take up comet Bennett, several did reach naked-eye vis- hunting until his mid-40s. He was only an ibility and were of scientific interest, too. off-and-on amateur astronomer until 1970, Spectra o f C/1974 C1, for example, were when Comet Bennett vaulted into the among the first to show bands of ionized predawn sky. It got him thinking that he water in a comet. could find a comet, too. Bradfield found his last comet in 2004, B y 1976 Bradfield was already a celeb- and it was his best. After it rounded the rity, having made six comet finds in as Sun, C/2004 F4 entered the morning sky. many years. A detailed account of the visit As comet expert John Bortle recalls, “For S&T’s Dennis di Cicco and I paid him that a week or so it remained an extraordinary October appears in the April 1977 issue. sight, with a bright 3rd-magnitude starlike His comet-hunting telescope had been head and a very long, narrow, and wispy cobbled together by a fellow amateur and tail that could be traced for 12° or more.” was equipped with a giant, 6-inch Dall- None of Bradfield’s 18 comets w ill meyer camera lens, made a century earlier return to the Sun’s vicinity anytime soon. We are not likely, either, to see another DENNIS DI CICCO visual comet hunter as persistent, clever, S&T: To read the full obituary, please visit and successful as Bill Bradfield. Bill Bradfield, seen with his unusual comet- skypub.com/bradfieldobit. ■ Ir o g e r w . s in n o t t seeking telescope in Australia in 1976. IN BRIEF Titan Sheds Light on Exoplanets. Cassini used Cassini to observe Titan as the hazy approaches, wind speeds might rise and blow observations of Saturn’s largest moon suggest moon passed between the Sun and the space- ripples across the ethane-dominated seas. that astronomers have oversimplified how a craft. Surprisingly, the team did not see the Writing in Nature Geoscience, Jason Hof- thick layer of haze might affect an exoplanet’s featureless spectrum they expected. Instead, gartner (Cornell University) and colleagues appearance, Tyler Robinson (NASA Ames Titan’s haze extinguished bluer light much report the detection of a small assemblage Research Center) and colleagues report in more effectively than redder light, creating o f something that appeared and disappeared the June 24th Proceedings ofthe National a complex spectrum that carries more infor off the coast of a peninsula in the northern Academy o f Sciences. Astronomers study the mation at longer wavelengths. So it appears sea Ligeia Mare in 2013. To the eye, the tran- atmospheres o f distant worlds by observing future telescopes might have better luck peer- sient features look kind of like an extension the chemical fingerprints that the exoplanet’s ing through planets’ clouds at redder colors. of the peninsula, but they don’t match what atmosphere imprints on starlight that passes ■ SHANNON HALL would be expected for image artifacts or ter- through it. But a few well-studied exoplan rain momentarily revealed by tides. Instead, ets show a lack of spectral features. Just as Sea Changes on Saturnian Moon. Fleet- the most likely explanations are transitory clouds on Earth appear white because they ing radar features in a sea in Titan’s northern phenomena such as waves, bubbles (perhaps absorb and scatter light equally across a wide hemisphere are tantalizing evidence of sea- o f gas released from the sea floor thanks to wavelength range, these enigmatic exoplanets sonal changes. Thus far the Cassini spacecraft changing temperatures), or the Titan version likely have a high-altitude layer of clouds or has seen only smooth lakes, but plan of silt suspended or floating in the sea. ♦ haze. To better study clouds’ effects, the team etary scientists suspected that, as summer ■ CAMILLE M. CARLISLE 18 October 2014 SKY & TELESCOPE Peculiar Galaxies Great Globulars ATIK 314L+ ATIK 460ex ATIK 11000 Comets INNOVATIVE For a complete list REFINED of ATIK camera ■ ■ ■ CAMERAS dealers please visit our website AFFORDABLE www.atik-cameras.com Pictures by Evangelos Souglakos, Nick Howes, Jeremy Skuza, Leonardo Orazi, Antonios Rossolatos and NASA/JPL-Caltech/R. Húrt (SSC) /® / Galactic Astronomy Battle of the Titans: The Milky Way vs. Androm eda The Milky Way and Andromeda galaxies vie for Local Group supremacy. 20 October 2014 sky & telescope MICHAEL RICH blows in the form of tides (see “Tides,” page 22). Numer- Astronomers have long known that the ous other dwarfs have suffered the same fate, and their M ilky Way and Andromeda galaxies are remaining tidal streams litter the M ilky Way’s environs. approaching each other at 300 kilometers M31 features a whopping 500 globular clusters. It has per second. Thanks to the Hubble Space three noteworthy galaxy companions, each roughly as Telescope’s exacting measurements of the relative motion massive as the Magellanic Clouds: the dwarf compact of the two galaxies, it’s a virtual certainty they w ill engage elliptical M32, the dwarf elliptical M110 (also known as in a massive prizefight 3 to 5 billion years hence, with the NGC 205), and the spiral M33. In addition, M31 has nearly result being a merger that w ill ultimately create a giant 40 identified dwarf satellite galaxies, with potentially red elliptical galaxy. Sim ilar bouts can be seen in progress many more to be discovered. right now: interacting spirals such as the Mice and the It appears that M32 has punched through the disk Antennae that w ill someday merge into ellipticals. of M31 at least once. Although not scoring a knockout, There w ill be no knockout in our contest, but it’s this blow very likely cost M31 its grand-design spiral interesting to consider how the two champions match up. structure, leaving instead two rings of star formation, Indeed, it’s a surprisingly even competition, even though including the prominent Ring of Fire that surrounds the our contestants look quite different at first glance. galaxy’s nucleus at a distance of 30,000 light-years. First Our galactic neighborhood, the Local Group, is a rela- suggested as a possibility in 2006, recent simulations tively small cluster of galaxies about 6 m illion light-years strongly suggest that the Ring of Fire is a consequence of across. It’s dominated by the M ilky Way and Andromeda M32 plowing through M31’s disk 210 m illion years ago (M31), whose centers lie 2.5 m illion light-years apart. Our and triggering density waves in the gas that led to a burst cluster hosts about 100 far less massive galaxies, includ- of star formation. ing M33 and the Magellanic Clouds. Think of the Milky Astronom ers have weighed both contestants by apply- Way and Andromeda as two major cities, flanked by ing Kepler’s law to the motions of each galaxy’s most numerous small suburbs — the dwarf galaxy members of distant satellites. In terms of total mass — 90% or more the Local Group. in the form of dark matter — both galaxies appear sim ilar to the level of accuracy that we can measure: slightly Sizing Up the Contestants greater than 1012 solar masses. Our perspective within In our corner stands the M ilky Way Galaxy. W ith its two the M ilky Way makes these measurements somewhat major star-forming spiral arms and ancient central bar more difficult, and determining the total mass (includ w eighing in at 20 b illio n Suns, the M ilk y W ay rules a reti- ing the dark matter) of either galaxy requires painstaking nue of nearly 160 globular clusters and 26 known dwarf measurements of the motions and velocities of a relatively galaxies. These include the prominent Magellanic Clouds, small number of distant satellite galaxies as well as mod- whose mass including their dark matter may be as high as 10% that of the M ilky Way — respectable galaxies in their own right, with their own systems of globulars (S&T: Oct. 2012, p. 28). Both the Large and Sm all M agellanic Clouds are very likely newcomers to the M ilky Way’s envi- rons, and both are wreathed in a stream of hydrogen gas (the Magellanic Stream) that winds around our galaxy. The Sagittarius Dwarf Spheroidal Galaxy has mistak- enly challenged the M ilky Way: no bantamweight beats a heavyweight. Sagittarius has wrapped itself around our galaxy, with its core some 60,000 light-years from our galaxy’s center. Sagittarius’s stars w ill ultimately dissolve fi \/ into the M ilky W ay’s halo in a process that has probably repeated itself many times over the past 10 billion years. In dominating the Sagittarius dwarf, the M ilky Way doesn’t even have to lift a glove: gravity is delivering the The Milky Way and Andromeda galaxies are moving inexora- bly closer, and will collide in 3 to 5 billion years. This photo If we could view our galaxy face on, it might look some- illustration depicts M31 and the Milky Way’s galactic plane thing like this depiction from astronomer and artist Robert looming large in the night sky when the two galaxies have Hurt. We’d see a prominent central bar and two major come close. By this time, the expanding Sun will have roasted spiral arms that mark regions with active star formation. Earth to a cinder. NASA / ESA / Z. LEVAY / R. VAN DER MAREL (STSCI) / T. HALLAS / A. MELLINGER NASA JPL-CALTECH HURT R. / / (SSC-CALTECH; SkyandTelescope.com October 2014 21 Galactic Astronomy Local Group \ Sextans V Sextans A A T Leo A z NGC 3109 ' Antlia Dwarf Canes Venatici Dwarf Leo I Leo II Ursa Major I _ Sextans Dwarf • 7Ursa Major II -Ursa Minor Dwarf IC 10 ---Draco Dwarf Large Magellanic Clouds Milky Way Galaxy Small Magellanic Cloud^ Sagittarius dSph Carina Dwarf • NGC 147 1 Sculptor Dwarf Fornax Dwarf ' M110 Andromeda I Andromeda Galaxy (M31) NGC 6822 ‘ M32 M33 Andromeda II Andromeda III Phoenix Dwarf . Pisces Dwarf ” ------^ X Aquarius Dwarf IC 1613—. Sagittarius DIG , Pegasus Dwarf ______Cetus Dwarf" ' Tucana Dwarf z ' W LM S&T: LEAH TISCIONE The Milky Way and M31 dominate the Local Group, depicted in Tides this illustration of its brightest members. This small cluster has roughly 100 galaxies stretching across 6 million light-years. The Earth is affected by tides that raise the seas twice two big boys contain the large majority of the total stellar mass. a day. But as manifestations of gravity, tides affect galaxies too. Gravity is a “central force” — the force eling the motions of galaxies in an expanding universe. is a vector, having a magnitude and a direction that Astronomers are still debating the numbers; depending always points toward the center of mass. In our daily on the Sagittarius dwarf galaxy’s orbit, the M ilky W ay’s experience of gravity, we feel the same gravitational mass might be a factor of two lower than the canonical force throughout our bodies. But for very large objects 1012 Suns. in a gravitational field, such as a satellite galaxy orbit In terms of sheer size and brightness, M31 has the ing our Milky Way, or eventually, when M31 and the edge. It’s challenging to estimate the M ilky W ay’s total Milky Way come closer, one side feels a much stronger brightness from a vantage point within it, but it has an amount of force than the other, giving rise to a stretch- absolute visual magnitude of about -20.5. Best current and-squeeze effect. On galactic scales, the difference estimates find M31 to have about twice the brightness in in gravitational force can cause stars to wander away stars, making it roughly one magnitude brighter. The eas- from the parental herd. It’s this tidal force that’s tear ily visible part of M31’s disk of stars and gas is a whopping ing apart the Sagittarius Dwarf Spheroidal Galaxy, and 150,000 light-years across compared to the M ilky W ay’s that ultimately plays a major role in disassembling still impressive 90,000-light-year-diameter disk. Both great galaxies as they collide. galaxies have halos of stars and dark matter that extend far beyond the visible disk of stars. The stellar mass of M31’s ROBERT M31: GENDLER: INSET: NASA / MICHAEL RICH (COLUMBIA UNIV.), AL. ET 22 October 2014 sky & telescope ! ' l * »* v ' . • •. ■ ‘ *x •* . • • *.tr • •, \ \ ' ’ a * " .* • ’ • ' • . * • M31 has about twice as many stars as our Milky Way and a larger visible disk, but it lacks spiral arms. The satellite galax ies M32 and M110 are to M31’s upper center and lower left. Left: The author used Hub- ' ble to capture the Androm- # eda globular cluster G1, the largest globular in the Local , Group. G1 has a black hole of about 20,000 solar masses, and is the only globular with strong evidence for a mas- ___ sive black hole. 24 Galactic Astronomy Galactic October2014 NASA / ESA / PAUL GOUDFROOIJ (STSCI) S&T: GREGG DINDERMAN 4710 has a central bar, which resembles a peanut from the side. side. the from peanut a resembles bar,4710which central ahas distance, we’d see galaxies that resemble NGC 4710 NGC resemble that galaxies see we’d distance, larger and more extreme. Both images were taken by Hubble. by taken were images Both moreextreme. and larger M104’smuch is bulge although Galaxy), M104Sombrero like (the M104 large M31a onfrom and edge Way Milky the view could we If Note the faint X-shape flare. M31 has a more spherical bulge, spherical more M31a has X-shapeflare. faint the Note K & escope p o c s le e t & SKY (below, page), facing respectively. Like the Milky Way, NGC NGC Way, Milky the Like respectively. (below) and The Sombrero (M104) has an extreme case o f a classical classical f a o case extreme an has (M104) Sombrero The tic bulges appear to come in two flavors: bars such as the the as such bars flavors: galac-two in entral come C to rate. appear bulges star-formation tic feeble a has and galaxy bars. inent prom feature a ith w lobes, galaxies X-shaped in has mon also com galaxy our peanut that a n have know bulges these side, formed the galax have to From spiral r disk. appears the ilia bulge m the from fa 4565, in C other G But N and as ay bulges. W such y ies their ilk M our f o especially case the galaxies, uilt b and gas that bursts In contained also matter. ps f dark clum o these ps clum universe, have erging m early galaxies the that through size posits mat- in ation dark grown cold form f favored galaxy o idely w theory ter The galaxy. disk pure a as football- flattened, a into evolved region central isk’s d the proto- assive m pre-existing a buckled it from that gravity suggests own its odeling m under theoretical as otions, m abundance heavy-element same the roughly ancient an average, hosts that bar a see e’d w “above,” from on face Compared Regions Central the as any m as ice tw roughly stars, n illio b 600 to 400 has 3’ ug saott c smasv steMiky ’s. y a W y ilk M the as host. assive to m as appears ice M31 tw about kind is the bulge that’s M31’s and M31’s. as bulge, such round” “ galaxies ini-elliptical m and ’s, y a W y ilk M now ’s It bars. as appear they on, face viewed and shape, star-formation f the o fueling the to contributed that stars bar. central a ing form ately ltim u structure, gravitation, shaped the utual s m A history. ’sthrough y a W y interacted ilk and M the orbited in stars early ed form that disk stellar and shape ar’s b the both on onsidering C contain, Sun. ly our rising surp members ay W whose y ilk system M our stellar see could we f appearance I the is bulges. central differences eir f th o striking most f the o One M31 Way. masses. y ilk solar M n illio b 50 around is total ’s y a W y ilk around M totals bulge and disk One m ystery is how our M ilk y W ay was able to evolve evolve to able was ay W y ilk M our how is ystery m One In contrast, M31’s bulge looks more like an ellip tical tical ellip an like more looks bulge M31’s contrast, In 100 b illio n solar masses; the the masses; solar n illio b NASA / HUBBLE HERITAGE TEAM (STSCI / AURA) KECK / UCLA GALACTIC CENTER GROUP Independent teams led by m y U C L A colleague Andrea Andrea colleague A L C Suns. U y n m by illio led m 4.2 at teams in weighs hole Independent black central ’s y a W w h ich the bulge formed. first bulge the the in ich h w rightly b blazed likely onster m eda’s Androm heavyweights: ic f cosm o spectacular most the ong am was otspr siebakhls ttercnes h l y ilk M The centers. both their eda at holes Androm black and ay assive W y ilk superm M host the that evidence Hubble ing the f M31) o case the (in and telescopes largest realm s are quiet, except for a sm all cluster o f f young o cluster all sm a for except quiet, are s realm M87, as such galaxies tical llip of e class giant in holes billion-solar-mass black the in not central youth its lthough A in M31 quasar. a that high Its beast. possibility y’s a the W y raises ilk M mass our than measured assive m more Hubble es tim from hole black M31’s f o ates estim Best however. stars al dividu f in o velocities the ining determ by mass Ghez, and Reinhold G enzel (Max Planck Institute for for Institute Planck (Max enzel G Reinhold and Ghez, 2 25 roughly Suns, n illio 100m at it place observations laws. Kepler’s applying then and hole black the orbiting Extraterrestrial Physics, G erm any), have m easured this this easured m have any), erm G Physics, Extraterrestrial Space Telescope, astronomers have found overwhelm- overwhelm- found have astronomers Telescope, Space li yas t ie uldb h mpegsfo from gas ple am the by fueled life, f its o years n illio b Yet despite the black hole’s high mass, M31’s central central M31’s mass, high hole’s black the despite Yet M31’s central black hole easily w ins this contest, contest, this ins w easily hole black central M31’s U sing im age-sharpening adaptive optics on the w orld’s orld’s w the on optics adaptive age-sharpening im sing U Arches and Q uintuplet star clusters. The Arches has has Arches The clusters. inted m star recently the uintuplet by Q and exhibited as Arches ation, form star ith w resides peak” false “ this that suggest models young all sm a and Theoretical hole black the where not is t h lig visible i etri lotest wse n ope agnetic m complex and galac- f twisted The o old. site the years n also is illio m 2center tic about only are oths behem hole. black the orbit that stars f o disk a in in peak brightest The double. be to appears it because shining w ith 1 m illio n or more solar lum inosities. These These inosities. lum solar more or n illio 1m ith w shining some away. light-years 5 ’s it Instead, located. are cluster star eculiar p quite also is nucleus M31’s gas. little a and stars Andromeda’s Satellite Plane Satellite Andromeda’s galaxy formation struggle to explain its existence. its explain to struggle of formation theories galaxy and Way, Milky the around known is structure abuzz is region central ’s y a W y ilk M the M31, e lik n U and velocities ofM31 dwarf galaxies using red giants. We We giants. red using galaxies dwarf ofM31 velocities and row plane 1.3 million light-years across. Nothing like this this like Nothing across. light-years 1.3 million plane row nar-a in arrayed are 13dwarfs the of that showed recently distances measured has that France) Observatory, bourg of member a a team I’m 100 stars w eighing up to to up eighing w stars which contains a whopping whopping a contains which offset 5 light-years from the central black hole (arrowed), (arrowed), hole black 5central light-years the from offset background. or foreground the in are stars fainter the of most whereas range, close at hole black the 4.2-million-solar-massaof location the blackmarks that source radio strong a (arrowed), A* Sagittarius of grip the in caught of stars of dozens orbits the study to optics central Way’s Milky the shows 10-meterKeck telescopes region. Strangely, the brightest spot in visible light is light visible in spot brightest the Strangely, region. Near left: adaptive using are Astronomers light. infrared in region Far left hole. Most of the bright stars in this image are orbiting are image this in stars bright the of Most hole. : This remarkable image taken with one of theof one with image taken remarkable This : This Hubble image resolves M31’s central resolves image Hubble This e b org Iaa (Stras- Ibata Rodrigo by led SkyandTelescope.com SkyandTelescope.com 100 solar masses and and masses solar 100 million solar masses. solar million coe 04 25 October 2014 Galactic Astronomy The Milky Way’s central region features two large clusters of massive, highly luminous young stars, the Arches (left) and Quintuplet (right). How these clusters formed remains a mystery. M31 has no central star clusters of comparable size and youth. fields, and additional massive young stars are clustered systems. The oldest datable M ilky Way stars range from around the black hole. The origin of these stars is a deep 11 to 12.5 billion years. mystery, because the extreme tidal forces near the black Each halo also has streams of stars that are almost hole should prevent stars from forming, and we don’t certainly the debris of unlucky cosmic contestants — sys know an obvious way to move stars there in a short time. tems sim ilar to the Sagittarius Dwarf Spheroidal Galaxy. In an observational tour de force, Thomas Brown (Space The Galactic Boondocks Telescope Science Institute) and a team to which I belong Both galaxies have diaphanous, extended halos. M31’s imaged a number of different locations in M31’s halo and has been traced to a radius of 500,000 light-years — about found old stellar populations, as well as stars a few billion 50% larger than the M ilky Way’s. As mentioned earlier, years younger — a population we don’t see in the M ilky M31’s halo has an extraordinary endowment of 500 globu- W ay’s halo. Using the MegaCam imager on the 3.6-meter lar clusters, three times that of the M ilky Way. Almost Canada-France-Hawaii Telescope to cover an area of sky all of the globulars in both galaxies are ancient stellar nearly 20° x 20°, the Pan Andromeda Archaeological Sur- The Milky Way and Andromeda Compared MILKY WAY ANDROMEDA Globular clusters 160 500 Known satellites 26 38 Absolute magnitude -20.5 -21.5 Stars 200 to 300 billion 400 to 600 billion Mass ~1012 solar masses ~1012 solar masses Disk diameter 90,000 light-years 150,000 light-years Halo radius 300,000 light-years 500,000 light-years Central black hole 4.2 million solar masses 100 million solar masses Using the Canada-France-Hawaii Telescope, astronomers have found streamers of stars in M31’s halo — the remnants Star-formation rate ~2 solar masses per year ~1 solar mass per year of tidally shredded dwarfs that ventured too close to the giant. 26 October 2014 sky & telescope vey, led by Alan McConnachie (NRC Herzberg Institute of Astrophysics, British Columbia), produced a map of M31’s halo (from measurements of 10 m illion red giants) that shows spectacular streamers and arcs. The most promi- nent feature, the so-called Giant Stream, may be the debris left by the infall of a disk galaxy about the mass of M33. Another noteworthy feature of M31’s halo is its large population of stars with high heavy-element abundances. The typical star in the M ilky Way’s halo has around 2% the Sun’s iron abundance whereas the typical star in M31’s halo is 10 times more metal-rich than this. The new Hyper Suprime-Cam on the 8-meter Subaru Tele- scope, along with an advanced spectrograph currently being built, may help provide many more abundance and velocity measurements for M31 halo stars, helping settle the mystery of how and when this galaxy assembled. The planned Thirty Meter Telescope w ill also have a spectro graph capable of studying faint stars in M31’s halo. Stellar Populations Compared The recently decommissioned Galaxy Evolution Explorer (G ALEX) satellite produced one of the greatest M31 por- traits, combining far- and near-ultraviolet imaging (S&T: April 2012, page 20). The light of massive young stars illuminates the spiral arms, whereas the bulge is seen not by the light of young stars but by the ultraviolet light of ancient stars whose energy is produced by helium (not hydrogen) fusion. The spectacular G ALEX image belies a different real- ity. Although astronomers estimate that both M31 and the M ilky Way are currently forming about 1 star per year, both galaxies appear to be transitioning from a lively This image from ESA’s Herschel Space Observatory shows M31 in far-infra- star-forming spiral galaxy of youth to a quiescent, mas red light, revealing cold dust from which stars form. The prominent Ring of sive galaxy of maturity — a denizen of the so-called “red Fire circles the nucleus at a distance of 30,000 light-years. This ring of active sequence” populated by ellipticals and massive spirals. star formation might have resulted when galaxy M32 plowed through M31’s Most of M31’s light arises from older stars, and there disk 210 million years ago. This image also reveals a fainter outer ring. appears to be relatively few stars formed in the past 100 ESA / HERSCHEL PACS SPIRE / / J. / FRITZ GENT / U. million years. W ithin M31 there is one major exception: the Ring of Fire includes the molecular hydrogen (H 2) and carbon- Andromeda’s Three Big Black Holes monoxide (CO) gas needed to form new stellar genera- Unlike the Milky Way and its solitary supermassive black hole, tions. Still, our galaxy appears to have about three times Andromeda and its satellites host at least three. Besides M31’s 100-mil- more molecular gas than M31. It’s possible that M31 expe- lion-solar-mass monster, its companion elliptical galaxy M32 hosts a rienced more significant interactions (like the possible black hole of 2.5 million Suns. The nuclei of the nearby galaxies M33 and collision with M32) that caused it to form more stars than M110 have been inspected carefully with Hubble’s spectrograph and the the M ilky Way, and thus it used up its inventory of gas, or telltale signatures for supermassive black holes are lacking. Now con- that the formation of its more massive bulge encouraged sider M31’s peculiar globular cluster G1 (the most luminous and massive it to convert more of its gas into stars in its youth. globular cluster in the Local Group), whose appearance resembles a mini- M32, with a compact nucleus. Its odd appearance inspired me to search End Game for a massive black hole in its core. From analyzing the velocities of stars Precision Hubble measurements of the space motions of in the “ integrated” or unresolved light of G1’s nucleus, Karl Gebhardt the M ilky Way and M31 support the long-standing suspi- (University of Texas, Austin), Luis Ho (Carnegie Observatories), and I cion that these contestants are falling toward each other. found that G1 hosts a 20,000-solar-mass black hole. G1 remains the most widely accepted case for a very massive black hole in a globular cluster. However, the first blow w ill not take place for billions of years. In the early rounds, computer simulations suggest SkyandTelescope.com October 2014 27 Galactic Astronomy NASA / HOLLAND FORD (JHU), ET AL. / ACS SCIENCE TEAM / ESA This Hubble image of the Mice (NGC 4676) gives us a sneak preview of the Milky Way-Andromeda collision that will take place 3 to 5 billion years from now. Tidal forces create the tails that give the Mice its nickname. Regions of vigorous star formation appear blue. that spectacular tidal streamers w ill be expelled, mak- may have sparked additional star formation and depleted ing the M ilky Way/Andromeda pair potentially resemble much of its gas. M31’s Giant Stream and the M ilky Way’s the Antennae Galaxies (NGC 4038/4039), the Mice (NGC Sagittarius dwarf are both remnants of small galaxies that 4676), or perhaps after some time, the Atoms for Peace tangled with the heavyweights. Our M ilky Way’s central Galaxy (NGC 7252), with the M ilky Way appearing to arc bar more likely owes its existence to the force of gravity crazily over the entire sky as seen from the perspective of acting on the protodisk, and the bar channels gas to the our solar system (S&T: Oct. 2006, p. 30). The interaction galactic center where it forms spectacular star clusters. w ill set alight all the remaining gas in the two galaxies, A more precise comparison awaits a new generation and the end result w ill be the consumption of virtually all of studies of Andromeda, and future work on the Milky of the gas in spectacular bursts of star formation. Way that may reveal more details about its geometry Eventually, the M ilky Way and Andromeda w ill collide and clarify the structure of its spiral arms. Although and merge, forming a giant elliptical galaxy. Among the the M ilky Way and Andromeda galaxies have prominent more interesting finales w ill be the orbital dance of two disks and similar masses, they have strikingly different or even three supermassive black holes in the center of appearances, and their origins and histories remain to be that newly minted elliptical. Theory predicts that much of fully understood. The galactic contestants are now inexo- the gas in both galaxies w ill collide and flow to the center. rably moving quietly from their corners of the celestial If this occurs, a new quasar may flare for hundreds of ring toward their date with destiny. ♦ millions of years. If any of our descendants are around to view the bout, it’s unlikely they w ill be living on Earth. By Michael Rich is an astronomer at the University of Califor- then, the Sun w ill have evolved into a red giant and our nia, Los Angeles, who has studied M31 using the Galaxy planet w ill cease to be a comfortable place. Evolution Explorer (GALEX), W. M. Keck Observatory, The appearances of the M ilky Way and M31 have and the Hubble Space Telescope. He helped advance Neil likely been molded by their extensive history of absorbing deGrasse Tyson’s career in astronomy by serving as his Ph.D. cosmic blows. M31’s more classical bulge may reflect a thesis advisor at Columbia University. Rich also authored the merger in its youth, and passage of M32 through its disk feature article about GALEX in the April 2012 issue. 28 October 2014 sky & telescope Naturally stable & lightweight 4 A B&H Photo 1.800.606.6969 www.bhphotovideo.com Featured Dealers: Astronomics 1.800.422.7876 www.astronomics.com Hands On Optics 1.866.726.7371 www.handsonoptics.com Visit www.iOptron.com High Point Scientific 1.800.266.9590 www.highpointscientific.com for a complete list of dealers OPT 1.800.483.6287 www.optteiescopes.com Woodland Hills Telescopes 1.888.427.8766 www.teiescopes.net (Canada) All-Star Telescope 1.866.310.8844 www.aii-startelescope.com | The Dawn of Radio Astronomy Discovering the , v Radio Sun The wartime discovery of radio emissions from the Sun gave birth to ( ■ thefield of'solar radio astronomy. " ' J. Kelly Smith & David L. Smith In 1890 the famous American inventor Thomas A. Edison, spurred on by Heinrich Hertz's discovery of radio waves three years earlier, set out to prove that the active Sun was capable of emitting radio waves. But despite his (correct) conviction that these emissions should exist, the discovery of the radio Sun would not come for another 52 years. The search for these invisible electromagnetic waves included some of the most notable figures of the world's scientific community. Some failed in their quest because of primitive equipment, others because their efforts did not coincide with periods of vigorous solar activity. Still others failed because they did not recognize the significance of periodic radio static. Ultimately our star gave up its secrets serendipitously, testing the wits of the young radio physicist who finally identified emissions from the Sun using radar receivers during World War II. This discovery of the radio Sun expanded the view of our star by more than seven orders of magnitude, initiating the birth and explosive growth of solar radio astronomy. 3 ° October 2014 SKY & TELESCOPE Valiant Efforts Edison's interest in detecting radio emissions from the Sun shines through in a letter sent at his behest by his associate, Professor Arthur E. Kennelly, to Professor Edward S. Holden, director of the Lick Observatory in California. In the letter Kennelly explains: Along with the electromagnetic disturbances we receive from the Sun which, of course, you know we recognize as light and heat,. . . it is not unreasonable to suppose that there will be disturbances of much longer wavelength. If so, we might translate them into sound. Kennelly went on to ask Holden to provide details of solar activity for comparison with Edison's own results. At the time, Edison was in his “Iron Period” — a span o f 10 years during which he perfected his method of extracting iron from low-grade ore. H is radio tele scope was to consist of millions of tons of locally mined magnetite, surrounded by a suspended loop of well- insulated telephone wires that terminated in a suitable detector, possibly a telephone. The telescope was to detect kilometer-long radio waves by their inductive effects on the cable loop and the magnetite. Unfortunately, there is no record describing the performance or results of the experiment, but, if performed, it almost certainly failed. First, the massive receiver would have been too insensitive to detect solar radio emissions; second, kilometric radiation is blocked by the Earth's ionosphere, a fact unknown at the time. (Ironically, Kennelly actually codiscovered the iono sphere in 1902.) Although Edison was the first, he was not the only famous scientist to attempt this feat. Sir Oliver Lodge was a professor of physics at University College in Liverpool, England, with a lifelong interest in electric- ity and magnetism. In 1894 he gave a lecture before the Royal Institution in London on Hertz's work that included a demonstration of radio-wave transmission. During the lecture he proposed “to try for long-wave radiation from the sun, filtering out the ordinary well- known waves by a blackboard, or other sufficiently opaque substance.” MAGNETIC ARCS Left: Plasma outlines magnetic field lines arching between two active regions on the Sun. The discovery of radio emission from such regions in 1942 marked the birth of solar radio astronomy. EDISON’S ORE Thomas Edison sits at his ore mill in Ogdensburg, New Jersey. For a decade he worked to develop a method for extracting iron from low-grade ore. The radio tele scope he planned to build from that iron seems never to have materialized, nor did his extraction method prove profitable. SUN: NASA / SDO / AIA / EVE / HMI; THOMAS EDISON: U.S. DEPT. OF THE INTERIOR / NATIONAL PARK SERVICE / THOMAS EDISON NATIONAL HISTORIC PARK 32 The Dawn of RadioAstronomy of DawnThe October 2014 NRAO / AUI / NSF first constructed in Reber’s backyard in 1937,in backyard dish Reber’s parabolic in the constructed When first Virginia. West Bank, Green in site Observatory Astronomy erpool, the site o f his experim ent. In frustration, Lodge Lodge Liv frustration, strial In u search. d in ent. his in experim abandoned f his o achinery f o m site the bursts loud erpool, electrical detect from to radiation, enough ell solar interference w up pick the to functioned it but insensitive Unfortunately, too short proved waves ionosphere. receiver radio the penetrate f receiving to o capable enough was coincidentally, the remains telescope His survey. that during Sun quiescent that the Sun did em it radio waves. H ad he waited for solar it. solar proved for have ell waited w he ad ight H m he , waves. um radio it axim m em did in Sun the that he Nonetheless, and , days. m u few a im in after m solar search his his during abandoned 3,100 occurred Alps, ents Unfortunately, French level. easurem m sea the above in feet) (10,200 placed Blanc eters ann ont m M on ordm N ent equipm atmosphere, his f the o effects absorbing attracted the attention of pilots, who would circle over Reber’s Reber’s over circle would who pilots, of attention the attracted AATCMAPE PPER A M GALACTIC prototype for many of today’s radio telescopes. radio of today’s many for prototype radio first the produced Reber rain-makingmachine. a invented hadhe that neighbors his of by some speculation prompting defending his thesis, he considered it extrem ely probable probable ely extrem it considered he thesis, his defending the above rise To doctorate. f his o pursuit in scientist map of the sky, although he didn’t detect emission from the from emission detect hedidn’t although sky, the mapof water, rain of gallons collected also It look. better aget tohome i etrd95mtrrdotlsoea h Ntoa Radio National the at 9.5-metertelescope restored radio his Septem ber 1901 by Charles Nordm ann, a young French French young a ann, Nordm Charles 1901 by ber Septem True to his prom ise, he constructed a receiver that, that, receiver a constructed he ise, prom his to True A third, but again unsuccessful, attem pt was made in in made was pt attem unsuccessful, again but third, A escope p o c s le e t & y k s Grote Reber stands here in 1960in here with stands Reber Grote Serendipity Fizzlies Radio The then and , m u im in m a at was interference radio hen w noise when he wrote: he when noise accompany to known fadeouts f radio o the periods noise this preceded called paper a ton In New . W . sources. H 1936, in noise terrestrial to published static-like f traced a o be not bursts by could that disrupted was reception radio solar 1944.detect til was n didn’t u Sun he and the issions em Reber, f quiescence for he o ich h period w a sky, in nfortunately f the U o 1940. map in had 1939he y radio B published first orld’s w mid- observations. to the his sleep e completed would resum he eal then m and night evening the r fte A company. to idnight m from ents easurem m out Way. carrying y ilk M f the o plane the just from ing wavelength com a at worked that receiver third a ilt u b he failed. wavelengths, 33-centimeter money. 9- and to and tuned labor ers own his dish using parabolic backyard in 9.5-meter his a and in designer constructed antenna e radio a as tim job f galac o onths’ his m quit four discovery Reber Jansky’s arl radiation, K tic by 1937, inspired In nois. u n til they passed the C liffs o f Dover. They were accompa- were They Dover. f o undetected liffs C hannel C the passed lish g they En til the n up u way their made and the battleships, capital y’s an erm f G o two layer E the near or in originated radiation the that the f the o rectly l lthough A f arriva o meters. 23 f 17and o direction the wavelengths easured at m noise iya, M enichi K and O n the night o f February 11, 1942, during W orld W a r II, II, r a W orld W 11,during 1942, February f o night the n O ionosphere. ’sincor- rth a E f concluded o they Sun, the ith w corresponded source . W D. operator, ham ritish B 1938a In often flares. noise solar strong high-level this that noted and fizzlies” radio “ radio shortwave when periods reported had operators radio Chicago a ith w job new his to eters kilom 50 g rivin d signals detected he relief, great his To meters. 2 f o short i Ill heaton, W from engineer radio young a Reber, Grote H eightm an, came near to the correct explanation for the the for explanation correct the to near came an, eightm H radio Sun, radio f the o discovery the to prior years For results, negative f these o years two receiv- nearly by using sky, Undaunted radio the easure m to efforts l itia in is H Gneisenau, frequencies over frequencies At such times [when fadeouts occur] the writer has often occur] writer has the [whentimes At such fadeouts which on the receiver takes the form o f a smooth but loud but f smooth a o the receiver takes the form on which observed the reception o f a peculiar radiation, mostlyon radiation, f a o peculiar reception the observed charged particles from the Sun on the aerial. the on Sun the charged particles from of arrival bythe caused is This hissingpresumably sound. The last known unsuccessful attem pt was made by by made was pt attem unsuccessful known last The In 1939 two Japanese researchers, M in o ru Nakagam i i Nakagam ru o in M researchers, Japanese 1939two In schedule, observing intense an into launched then e H slipped out o f their births in Brest, France, France, Brest, in births f their o out slipped 10 Mc/s [or about [or about Mc/s 30 meters in wavelength],in meters Scharnhorst 6 a.m., a.m., and and U.S. NAVAL HISTORICAL CENTER PHOTOGRAPH jamming that enabled the daring passage impelled the British to British the passageimpelled daring the enabledthat jamming James Stanley Hey to identify radio emission from the Sun. the from radioemission identify to Hey Stanley James DASH EL NN A CH E TH a told it n U Interception Radio ritish B f the o allace W dark- in fleet the launched and tide favorable a for waited English the through sailed had fleet hostile a ada, Arm m onitor all reports o f radar jam m ing and, whenever pos- whenever and, ing m jam f radar o reports all onitor m to up are ans erm G the sure am I day. every worse me ting take chaps you ill W “ Intelligence, ritish B f o ber em m become. had it intense opera how that so days f radar o recognize to il ber fa ritish num B f a o over would tors ing m ents jam increm eir all th sm by increased had also ans They erm ness. G The error. an hum and luck, audacity, f approximately o escort an and boats), torpedo motor can 26 boats, iser pedo cru heavy the by nied mrv hi aa uvilne hscrfl monitoringenabled careful This surveillance. radar improvetheir Eugen, responsibility is h T countermeasures. to ent plem Group im to sible, Research Operational y rm A their ordered Office were. they indeed d n A get- is ething!” ing m som jam down the sets and ed, radar m our jam days been For have coast ill. the w on else one No seriously? Colonel frustrated a Dash, hannel C the before day One through. got one this ada, Arm the e lik n u But, Spanish the Channel. since e tim first the For planes. fighter 280 make their way up the English Channel in February 1942. February in Channel radarEnglish The make upthe way their The C hannel Dash succeeded due to a m ixture of of ixture m a to due succeeded Dash hannel C The In response to this catastrophic failure, the B ritish W ar ar W ritish B the failure, catastrophic this to response In the Nazi battleships battleships Nazi the schnellboots Photographed from the cruiser cruiser the Photographedfrom Gneisenau Prinz Eugen, Prinz (i lrt Brts adAmeri e m A and ritish B to ilar (sim (closer) and (closer) 6 etoes 14 tor- destroyers, Scharnhorst Prinz The interference was o f such intensity as to render radar radar render to as intensity such f o was interference The had who physicist young a ey, H Stanley es Jam to given was variable the discovered and meteors study to radar use to first Research Operational Army the with working while Sun the from exceptionally active sunspot was in transit across the solar solar the across transit an in that was learned sunspot and active telephoned he Observatory ich exceptionally Sun, the reenw G followed Royal the interference um axim m and 4 between f anti-aircraft o wavelengths ing at m jam e orking w daytim radar f widespread o activities. reports ing m served radar-jam ich h w ans’ team, erm G f his the o Dover at ber onitor em m m a to cliffs by the addi- on In anned m office. was laboratory that his to obile m a ing up m mandate set a f he jam o tion, included that instances ll a operators report to radar for instructions assignment. ilitary m his to prior anchester M from crystallography X-ray in y degree rm A aster’s the m at training f intensive o weeks six received just waves. radio emit does Sun the that revealing day, that radar British jammed meridian central Goodof Cape 27, February 1942,Observatory, onRoyal the at radio intense that confirm helped he war the After Group. disk at that tim e. H e later wrote: later e H e. tim that at disk of directions the that Recognizing possible. im operation A. Cygnus source radio the was also He flares. solar with associated often were bursts emission radio discovered Hey Stanley James operator radio ish LIBRARY UNIVERSITY / CAMBRIDGE OBSERVATORY GREENWICH ROYAL SUN: PRESS UNIVERSITY CAMBRIDGE HEY: U niversity in 1931 and taught physics in a gram m ar school school ar m gram a in physics taught 1931 and in his earned niversity U had ey H Surrey. , Petersham at School Radio the near sunspots the from emission Radio Africa. South Hope, N SU RADIO E TH F O VERER ISCO D generated centimetric radio waves from the motion o f f elec-o motion the waves radio from centimetric generated it not be possible for a sunspot region, with itsreservoir sunspotregion,with vast a be not itpossible for should why thought I and magnetic kilogauss tronsinfields, valves magnetron that knew I likelysource. the regionwas explained be direction in directly waves magnetic It was clear to me that the Sun must be radiating electro- radiating be must Sun the that me to clear was It Fbur 7had2t, 92 ews eue t ith w deluged was he 1942, 28th, and 27th February n O In cooperation w ith arm y officials, H ey devised devised ey H officials, y arm ith w cooperation In Right: —for how else could the coincidence the could else how —for — — This picture of the Sun was taken was Sun of the picture This and that the active sunspotactive the that and SkyandTelescope.com SkyandTelescope.com Left: Physicist and Brit and Physicist 8 meters. meters. October 2014 33 34 The Dawn of RadioAstronomy of DawnThe October2014 CSIRO from left to right are John Bolton, Gordon Stanley, and Joe Pawsey. andJoe Stanley, Gordon Bolton, right are toJohn left from Shown II. W W after radioof astronomy of growingthe field forefront S ER E N PIO RADIO AUSTRALIAN Southworth and Hey, Reber, f Jansky, o discoveries The perature at an astounding astounding In an at Sun. f the perature o properties al therm and agnetic band, electrom radio the in are the in plasma) hot movements electrons’ to magnetic-field-infused related (both atmosphere f the o growth astronomy. the for f radio o ground science Collectively, fertile had new radar provided f confidence. in o g factors in sense a these train ith e w investiga- artim them f the w o eir bued th im any M and no young, ilitary. m were receivers the tors and by used recorders, being state-of- to itters, longer access transm had they d aerials, n investigate A to the-art f radio. free o now uses e were ar w peacetim the during States. Brit- research and nited U the stralia u and A in Canada in first y in then period, astronom ar ain, radio postw in ediate m growth im the exponential an triggered f attention. o center the become to States. nited U the Sun. the from correctly he anated em Office, r a rather W ritish B f the f o lie re the to uch m sion of Radiophysics in New South Wales, Australia, worked at theworked Australia, Wales, South New in Radiophysics of sion 1945 A u stralian observers measured the corona’s tem- corona’s the measured observers stralian u 1945A war. the after til n u papers 1942discovery eir th distribute in Laboratories Telephone ll had e he B at that orking receiver w ile h w icrowave m a designed using radiation, solar but ade anm m not was ing m jam radar the that ised surm H e y’s discovery proved vital to our understanding o f f the o understanding our to vital proved discovery y’s e H soon was and lf e its revealed lly a fin had Sun radio the But and colleagues, f his o part the on skepticism Despite Postwar Boom Postwar generate metre wave radiation. wave metre generate o f energy and known emission o f corpuscular streams o f f ionso f streams corpuscular o emission f known energyo and and electrons in magnetic fields o f the order o f f f o order the o magnetic electrons in fields and Because two o f the natural frequencies o f the solar solar f the o frequencies natural f the o two Because electronics in involved scientists and Engineers not could orth Southw and ey H reasons, security For detected also orth Southw C. George year, that Later tel e p o c s le e t & y k s 1 m illio n kelvin, a finding that finding a kelvin, n illio m Members of CSIRO’s Divi- of CSIRO’s Members 100 gauss, to gauss, J. Kelly Smith is an emeritus professor of medicine at the at medicine of professor emeritus isan Smith Kelly J. James H. Quillen College o f Medicine at East Tennessee State Tennessee East at f Medicine o College Quillen H. James w h ich later proved to be cru cial to the discovery o f radio f radio o discovery the to cial cru be to proved later ich h w can ateurs (Am wavelengths. visible in see can one what two The sea. the from reflected other the and source the from ETER M TERFERO IN A E S ing the properties o f different layers o f the Su n ’s atmo- atmo- ’s n Su f the o layers determin- bursts, different f o radio tra- and properties in the orig classifying ing the flares, solar f tracking o for photosphere, the basis jectory a above height providing thereby increasing ith w speeds. increased relativistic to whose electrons flares, or accelerated sunspots had over operators itted radio energies em were shortwave ey by H by and described previously noises study f intense o subject the ains rem sunspots. of area the in originate emissions powerful most Sun’s the that show to technique this used McCready Lindsay and Scott, antenna The 1951in erected Australia. Sydney, near was ometer the Sun to visu alizin g the enorm ous radio energies of of energies radio ous enorm the g alizin from visu to gone Sun have the we century, a than less In thousands. are radio the uncloaking In pulsars. and quasars, galaxies, much-and pattern interference an form to superimpose signals solar radio astronomy. radio solar in interest special a with inventor isan Smith L. David son o f w h ich are located m illio ns o f light-years away. f light-years o some — ns stars illio m located exploding are and ich h holes, f w o black and pulsars, galaxy f our quasars, o center the from static there radio Today detecting Sun. the from issions em radio describing artin M ir S er astronom radio physicist radio ritish B the stralian and u A the Pawsey both Joe motivated Sun f the o article our see too; investigations, page on radio solar own beyond eir far th do distances at corona the observing and sphere, Payne- Ruby 1946 In Pawsey, Joe resolution. angular improved straight one paths, two along signal radio source’s upa picks Ryle and th eir colleagues to design radio interferom eters, eters, interferom radio design to colleagues eir th and Ryle issions em f radio o wavelength the that found Researchers Sun, these pioneers opened the door to a w ider universe. ider w a to door the opened pioneers these Sun, University and a long-time amateur radio astronomer. His astronomer. radio amateur long-time a University and hma Eio ol epesd ♦ pleased. be would Edison as Thom resolution angular better and better for desire the nd A One year later came proof that loud, sporadic radio radio sporadic loud, that proof came later year One In 1946 there were less than a dozen publications publications dozen a than less were there 1946 In 66 o f the February 2011 issue.) February f the o This eight-element Yagi sea interfer-sea Yagieight-element This (S&T: c. 02 . 16). p. 2012, Oct. CSIRO THE Understanding the Universe: ^ G r e a t An Introduction to Astronomy, 2nd Edition Taught by Professor Alex Filippenko C o u r s e s ' UNIVERSITY OF CALIFORNIA, BERKELEY LECTURE TITLES 1. A Grand Tour of the Cosmos 51. Our Sun’s Brilliant Future 2. The Rainbow Connection 52. White Dwarfs and Nova Eruptions 3. Sunrise, Sunset 53. Exploding Stars—Celestial 4. Bright Objects in the Night Sky Fireworks! 5. Fainter Phenomena in the Night Sky 54. White Dwarf Supernovae— 6. Our Sky through Binoculars Stealing to Explode and Telescopes 55. Core-Collapse Supernovae— 7. The Celestial Sphere Gravity Wins 8. The Reason for the Seasons 56. The Brightest Supernova C ourses- 9. Lunar Phases and Eerie in Nearly 400 Years Lunar Eclipses 57. The Corpses of Massive Stars 10. Glorious Total Solar Eclipses 58. Einstein’s General 11. More Eclipse Tales Theory of Relativity Understanding the Unive 12. Early Studies of the Solar System 59. Warping of Space and Time 13. The Geocentric Universe 60. Black Holes—Abandon An Introduction to 14. Galileo and the Copernican Hope, Ye Who Enter Revolution 61. The Quest for Black Holes 15. Refinements to the 62. Imagining the Journey Astronomy, 2nd Edition Heliocentric Model to a Black Hole 16. On the Shoulders of Giants 63. Wormholes—Gateways 17. Surveying Space and Time to Other Universes? 18. Scale Models of the Universe 64. Quantum Physics and 19. Light—The Supreme Informant Black-Hole Evaporation 20. The Wave-Particle Duality of Light 65. Enigmatic Gamma-Ray Bursts 21. The Color of Stars 66. Birth Cries of Black Holes 22. The Fingerprints of Atoms 67. Our Home—The Milky Way Galaxy 23. Modern Telescopes 68. Structure of the Milky Way Galaxy 24. A Better Set of Eyes 69. Other Galaxies—“ Island Universes” 25. Our Sun, the Nearest Star 70. The Dark Side of Matter 26. The Earth, Third Rock from the Sun 71. Cosmology—The Really Big Picture 27. Our Moon, Earth’s Nearest Neighbor 72. Expansion of the Universe 28. Mercury and Venus and the Big Bang 29. Of Mars and Martians 73. Searching for Distant Galaxies 30. Jupiter and Its Amazing Moons 74. The Evolution of Galaxies 31. Magnificent Saturn 75. Active Galaxies and Quasars 32. Uranus and Neptune, 76. Cosmic Powerhouses the Small Giants of the Distant Past 33. Pluto and Its Cousins 77. Supermassive Black Holes 34. Asteroids and Dwarf Planets 78. Feeding the Monster 35. Comets—Gorgeous 79. The Paradox of the Dark Night Sky Primordial Snowballs 80. The Age of the Universe 36. Catastrophic Collisions 81. When Geometry Is Destiny 37. The Formation of Planetary Systems 82. The Mass Density of the Universe 38. The Quest for Other 83. Einstein’s Biggest Blunder? Planetary Systems 84. The Afterglow of the Big Bang 39. Extra-Solar Planets Galore! 85. Ripples in the Cosmic 40. Life Beyond the Earth Background Radiation 41. The Search for Extraterrestrials 86. The Stuff of the Cosmos 42. Special Relativity and 87. Dark Energy—Quantum Interstellar Travel Fluctuations? 43. Stars—Distant Suns 88. Dark Energy—Quintessence? 44. The Intrinsic Brightnesses of Stars 89. Grand Unification & 45. The Diverse Sizes of Stars Theories of Everything 46. Binary Stars and Stellar Masses 90. Searching for Hidden Dimensions Uncover the Cosmic Clues 47. Star Clusters, Ages, and 91. The Shape, Size, and Remote Distances Fate of the Universe 48. How Stars Shine—Nature’s 92. In the Beginning Nuclear Reactors 93. The Inflationary Universe to Our Amazing Universe 49. Solar Neutrinos—Probes 94. The Ultimate Free Lunch? of the Sun’s Core 95. A Universe of Universes 50. Brown Dwarfs and 96. Reflections on Life and the Cosmos O u r world is part o f a vastly larger cosmos. B u t how large is it? W here do Free-Floating Planets we fit in? H o w did it all begin? These questions have puzzled stargazers for thousands of years. But only in our own time has the full picture of the true Understanding the Universe: immensity, variety, and surpassing strangeness o f the universe come into focus. An Introduction to Astronomy, 2nd Edition Course no. 1810 I 96 lectures (30 minutes/lecture) Understanding the Universe: An Introduction to Astronomy, 2nd Edition, is a nontechnical look at where that picture stands today. In 96 richly illustrated half-hour lectures from Professor Alex Filippenko, a S A V E $ 5 7 0 world-class researcher and an eight-time winner of “ Best Professor” at the University of California, Berkeley, you will survey the main concepts and DVD $799.95 NOW $229.95 discoveries in astronomy, from constellations drawn by the ancients to +$30 Shipping, Processing, and Lifetime Satisfaction Guarantee recent images captured by telescopes probing the farthest frontiers. Priority Code: 95845 Offer expires 09/20/14 For 24 years, The Great Courses has brought the world’s foremost educators to millions who want to go deeper into the subjects that matter most. No exams. No homework. Just a world of knowledge Th e G r e a t C o u r s e s .c o m /3s k y available anytime, anywhere. Download or stream to your laptop or PC, or use our free mobile apps for iPad, iPhone, or Android. 1-800-832-2412 Over 500 courses available at www.thegreatcourses.com. you really can see stars and planets during the The innermost planets actually show more detail dur- daytime. Venus is surprisingly easy to spot if ing the day than at night. Mercury never strays far from you know where to look, and Jupiter is also visible without the Sun, so it’s low in the sky whenever the Sun is below optical aid. A telescope expands the possibilities greatly, the horizon. That means that the image is blurred by showing all of the classical planets as well as stars down passing nearly horizontally through the atmosphere. Your to 4th magnitude. That’s beyond the naked-eye nighttime best chance for a clear view of Mercury’s surface features lim it in some brightly lit cities! is to catch it between sunrise and sunset. Even if you can do this, why would you bother? Partly, Unlike Mercury, Venus is occasionally high at night it’s the challenge. The Sun is easy, but spotting your time. But Venus is blindingly bright when viewed against second star in daylight is a memorable experience. Who a dark background. The daytim e sky tames Venus’s other- would guess that you can pick a star out of the featureless wise overwhelming brilliance, and may even allow you to blue ocean overhead? Yet the brightest stars stand out glimpse subtle features in its uppermost cloud deck. surprising well through a telescope, and their appearance Some things can only be seen during the day. Venus is striking when surrounded by blue sky. Sharing this is most spectacular near inferior conjunction, when it’s experience can be effective public outreach. You’re more almost directly between Earth and the Sun. It’s so close visible during the day, when people are out and about, and to Earth then that its razor-thin crescent is much longer you can pique their interest with the unexpected. from tip to tip than Jupiter is wide. Likewise, many com- 36 October 2014 sky & telescope Broad Daylight You don’t need to stop observing just because the Sun is above the horizon. ©BIGSTOCKPHOTO.COM GRISHA / BRUEV ets are at their brightest when they’re closest to the Sun, A safe solar filter w ill enable you to align your tele visible only in the daytime sky. scope accurately by centering the Sun in the eyepiece. Lunar occultations, when the Moon passes in front of It w ill also allow you to view this most spectacular of all a planet or bright star, are rare and spectacular. Occul- daytime objects. O f course, you must never look at the tations are equally common at day and night, so being Sun through a telescope, finderscope, or binoculars with- versed in daylight observing techniques doubles your out using a safe solar filter. chances of catching these events. Detecting objects in daylight is a different challenge from detecting faint objects at night. I find that the sweet Equipment spot for detecting stars during the day is around 6 inches The hardest part of daylight observing is locating your of aperture. Larger scopes may show additional details on target. That traditionally required equatorial mounts the planets, but poor daytime seeing tends to turn stars equipped with setting circles, and some people use Dob- into fuzzy, quivering masses. To minim ize this effect, sonian telescopes with homemade alt-azimuth setting keep your telescope in the shade and try to observe over circles. But modern Go To and Push To mounts make grass rather than hot asphalt. this feat much easier. A finderscope can be a big help in It’s a good idea to pick out one eyepiece and stick with locating Venus, Jupiter, and the brightest stars, especially it if possible. The simple act of switching eyepieces can if your pointing system has limited accuracy. cost a lot of time due to the difficulty of recovering focus. SkyandTelescope.com October 2014 37 Daytime Astronomy S&T imaging editor Sean Walker prefers to study Mercury (far left) and Venus during the day. These photos accu- rately capture what he saw through the eyepiece of his 12-inch Newtonian. Instinct would lead you to select a low-power eyepiece Practicing in the Dark because it w ill be easier to get an object into the field of Most of the hard work of locating objects during the day view, but I find that mid-power eyepieces are easier to w ill already be done if you have a permanently mounted focus. Relatively high magnifications also yield a darker scope that routinely locates objects near the center of the sky background, which is particularly useful for detecting eyepiece and doesn’t need training during startup. But if stars. A 1° field of view that shows the Moon with plenty you need to assemble and initialize your equipment each of room to spare is ideal. time you use it, then it pays to practice in the dark. It’s also helpful to optimize your scope and eye. Proper During the day you can align your scope on the Sun, baffling w ill boost a scope’s contrast. Owners of Newto- but that’s obviously not available at night. The Moon nians can leave the bottom tube cover on to block stray makes a great substitute, and it’s also a fine secondary light. SCT and refractor owners can use a dew shield. alignment point during the day, assuming that it’s above Fine-tuning the collimation makes star images as tight as the horizon. However, the Moon’s position varies consid- possible. Those of us with astigmatism may want to leave erably due to parallax; people viewing the Moon simul- corrective lenses on. taneously from different locations may see its position among the stars vary by a degree or more. Most Go To and Push To mounts take your location into account, but some do not. It’s wise to find out at night! Once you’ve aligned on the Moon, you can practice the skills needed to find Venus. Venus is typically about 2 hours of right ascension (30° in the sky) from the Sun, so use your system to locate an object that’s about that distance from the Moon. You’re allowed to use your finderscope during this exercise, because Venus is readily visible in a finderscope during the day. For all systems, locate a few of the bright stars in the Winter Hexagon or Summer Triangle, depending on the season. For German equatorial mounts, try to incorpo- rate a “pier flip” to see how well the pointing accuracy survives as you cross the meridian. If the mount loses accuracy after the flip, note the discrepancy so that you can compensate for it during your daytime session. Use short hops to the brightest stars to work your way across the sky. Resynchronizing the scope as you go minimizes the demands on the pointing accuracy. Spiral search functions can help land an object in the eyepiece. And faint points of light may catch your eye bet- ter when the scope is moving than when it’s stationary. If you can align your scope during the night and leave German astrophotographer Stefan Seip used a polarizing filter to it “parked” until the next day, by all means do so. And darken the sky while photographing Comet McNaught (C/2006 even with the simplest equipment, you can locate your P1) just after perihelion, on the afternoon of January 13, 2007. target before dawn and keep tracking it as the Sun rises. 38 October 2014 SKY & telescope When and Where to Look Picking the right time to observe is the first key to suc- cess. Choose a dry day with a beautifully deep blue sky. The second day after a cold front comes through is often best; the first day tends to have clear but unsteady air, preventing pinpoint star images. The daytime sky’s brightness varies greatly. It’s relatively dark just after sunrise or before sunset; the sky becomes much brighter when the Sun is high. At any given moment the sky is brightest near and below the Sun, and it’s darkest high above the horizon and at least 90° from the Sun. The Winter Hexagon and Summer Triangle are well placed around the equinoxes, when the air is often clearest. Venus is the easiest object to locate during the day besides the Sun and Moon. It’s obvious in any instru- ment, and it’s spectacular through a telescope, especially during its crescent phase. Jupiter is a runner-up for Princeton University professor Robert Vanderbei used this detectability, but it appears washed out, making its belts equatorially mounted 3.5-inch Questar to capture the Jupiter hard to see. Mars and Mercury vie for third and fourth image shown on the following page. Note that the scope is set place; both planets vary greatly in brightness and detect- up in the shade to minimize tube currents and eliminate the ability. Saturn is dimly lit because it’s so far from the Sun, possibility of pointing the scope unintentionally at the Sun. so it appears barely brighter than the background sky. But keen eyes may detect its rings as an apparent defect or elongation of the disk. PRESERVING ALIGNMENT The brightest stars pierce the daylight sky surpris- ingly well; they’re even visible through finderscopes and Polar-align your scope at night. If you can’t leave it set up un- binoculars when they’re reasonably far from the Sun and til your daytime session, mark the locations of the tripod feet the air is clear. Star colors are visible through a telescope, so that you can set it up with the same orientation. A bubble although not as obvious as they are at night. Red stars or torpedo level can be a great help with alt-azimuth mounts such as Betelgeuse make a nice contrast in color against as well as equatorial mounts. These steps will maximize your the blue sky. When the seeing is good, 2nd-magnitude pointing accuracy if you must calibrate your system using stars look like perfect little dots — a neat effect. only one object. Your First Daylight Observing Session The most important thing to bear in mind is that daytime observing can be dangerous. Even a momentary glimpse of the Sun can blind you, and the Sun can set objects near the eyepiece on fire if it drifts through the field of view while the scope is unattended. So make sure that you keep both the main scope and the finderscope capped when you’re moving the scope, or anytime you’re not actu- ally viewing your target object. It’s much safer to set up a telescope in the shade. This w ill also prevent tube currents from harming the image. If you need to align on the Sun, try to set up in the afternoon just outside the shadow of a building, and then start observing once the shadow has covered the scope. Alternatively, use a beach umbrella to shade the scope after doing the alignment. Determine your targets in advance using a planetarium program, a sky app on a handheld device, or the free S&T editorial intern Maria Temming demonstrates an iOptron skychart at skypub.com/skychart. If you’re using traditional Go To mount that makes locating planets and stars during setting circles, find the precise offsets of your targets from daylight much easier. DENNIS DI CICCC the Sun and/or Moon. S&T: SkyandTelescope.com October 2014 39 Daytime Astronomy Sky & Telescope editors gathered around midday on November 9, 2004 to watch the thin crescent Moon occult Jupiter. Good focus is critical for detecting stars during the day If Venus is visible, it makes an excellent second or time. You can focus on the Moon, the edge of a cloud, or a third alignment point. It’s a short hop from the Sun, and tree or building at least 1,000 yards (or meters) distant. often from the Moon, so pointing accuracy isn’t crucial. If you were able to align your system the previous night It’s also bright enough that you w ill see it easily in your and leave it running, see if it’s still accurate enough to finderscope. Once you have Venus in the center of the locate your targets. Otherwise, you w ill need to fall back on eyepiece, sync on it to improve pointing accuracy. I use the techniques that you practiced in the dark. Align your Venus as a trusty anchor to come back to if I lose my scope on the Moon if it’s visible. You can get a crude fix way. Jupiter also works well, but it’s not as obvious in a on the Sun by minim izing the shadow that your telescope finderscope. casts on the ground. If you have a safe solar filter, you can From Venus you can move on to any of the bright stars make this much more accurate by centering the Sun in in the Summer Triangle or Winter Hexagon, just as you your telescope’s eyepiece. did at night. When going for a star, bear in mind that Vanderbei's daylight Jupiter image, also S&T editor Gary Seronik photographed taken with a Questar as shown on the Jupiter disappearing behind the Moon previous page, captured amazing detail through his 3.5-inch Questar. on the planet's disk. 40 October 2014 sky & telescope even if focus is perfect, the star may be at the edge of the field and distorted. Once you capture the star, try moving it around the field to see how the visibility changes. If you wear eyeglasses, view with and without them to see which you prefer. As you get used to picking stars out of the day light sky, you can move on to more challenging fare. Pushing the Envelope Now that you can locate the brightest stars, try looking for 2nd-magnitude stars. Start with a constellation in the darkest part of the sky. The Sun never comes near the Big Dipper or Cassiopeia, and at least one of those patterns is always fairly high for northern observers. Double stars can make a good test for your lim it ing magnitude. Second-magnitude Mizar has a 4th- magnitude companion just 14" away. Alcor is as bright as M izar’s companion, but it’s tough to locate because it’s 50 times farther from the anchor star. In any case, 4th-magnitude stars are tricky to spot. But once you’ve captured those little flecks in the eyepiece, they’re much easier to hold. The ultimate daytime observing prize is a naked-eye sighting. Spotting a planet when the Sun is up can give John Kielkopf took this all-sky panorama of the University of Lousiville’s Moore Observatory late on the afternoon of February 27, 2007. The darkest you a unique feeling for our place in the solar system — part of the sky lies opposite the Sun and well above the horizon. The pinkish especially when the Moon is in the scene too. artifact toward the right is lens flare. Venus is visible without optical aid on any clear day as long as it’s reasonably far from the Sun and also higher than the Sun in the sky. Jupiter is surprisingly easy to determine the angular separation between the Sun and hold in view immediately after sunrise, but it’s very hard Venus. Try to visualize how the ecliptic arcs upward from to locate later in the day. Any object is easiest to find when the Sun in the sky, and measure out that angle. Then it’s near the Moon, and the Moon also gives you a target to locate Venus in binoculars. focus on — a feat that’s difficult to accomplish when look A parking lot with a flagpole is useful for the next ing high in a featureless blue sky. trick. W alk around until you place the flagpole directly Fam iliarize yourself with the method of approximat- below Venus, then put down the binoculars and look for ing angles with your fist held at arm’s length, which Venus with your unaided eyes. A tree can work well, too. measures out about 10°. Use an almanac or computer to But if the tree or flagpole is nearby, you may have trouble focusing beyond it to spot Venus. The same technique works for Jupiter, though you probably need to be within 2 hours of sunrise or sunset. March 2015 presents ideal geometry for observers at mid- northern latitudes, with Jupiter high in the east in the late afternoon as the Sun descends in the west. An even bigger prize may be available for those in the Southern Hemisphere, where the geometry is favorable for spotting Sirius before sunset in March. As you locate more stars and planets during the day, consider this: In addition to your amateur-astronomy brethren, there’s another group that can boast of seeing stars when the Sun is in the sky — astronauts! ♦ Robert Vanderbei was able to image Messier 42, the Great Orion Nebula, through a 10-inch scope 15 minutes after Chris Dalla Piazza has been an amateur astronomer and sunrise on September 9, 2007. The key to this exposure was astrophotographer since 1992. He would like to thank the shooting through a hydrogen-alpha filter, which like any red members of the Astronomical Society of Harrisburg for filter greatly reduces the brightness of the blue daytime sky. nurturing a lifelong love of astronomy, and Robert Job in particular for his first daytime view o f Venus. SkyandTelescope.com October 2014 41 New Product Showcase Y EYEPIECE PROJECTION CNC Parts Supply unveils VariMax ($129), the largest variable eyepiece projection adapter for DSLR cameras available today. This CNC-machined adapter allows you to use any 1^-inch eyepiece on the market with your digital camera to capture closeups of the Sun, Moon, and planets. Its wide housing can accommodate the largest 1^-inch-format eyepieces with an upper housing diameter of up to 2^ inches and 3^ inches in height. VariMax attaches to any T-ring adapter and is extendable up to 1.26 inches, and its laser-engraved scale enables you to repeatedly set the perfect dis- tance for photography with your favorite eyepieces. VariMax attaches to your telescope with a 1^-inch barrel or optional 2-inch adapter. CNC Parts Supply, www.telescopeadapters.com A PORTABLE PRECISION iOptron announces the iEQ45 Pro ($1,848), a portable German equatorial Go To mount. Weighing 25 pounds (11 kg), the mount offers many improvements over its predecessor, the iEQ45. Featuring precision stepper motors, 256- and 228-teeth aluminum right ascension and declination gears, respectively, the iEQ45 Pro boasts zero backlash to pro- duce error-free tracking during long-exposure astrophotography. The unit’s electronics are controlled via the Go2Nova 8407 hand controller that includes a database of more than 350,000 objects, and can slew at speeds of up to 1,400x sidereal rate. Its 6-inch dovetail saddle plate accepts both Vixen and Losmandy-style dovetail bars. The mount includes a heavy-duty stainless-steel tripod, an illuminated AccuAlign G2 polar scope, and DC power supply. See the manufacturer’s website for additional details. iOptron, 6F Gill St., Woburn, MA 01801, 866-399-4587; www.ioptron.com DOB CONTROL Add stability and slow-motion controls to your Dobsonian telescope with ZLOMOTION ($349). The ZLOMOTION accessory kit attaches to your 8-, 10-, or 12-inch Zhumell, Apertura, and Sky-Watcher Dobsonian telescopes with stainless-steel and brass hardware requiring only minor modifications. The kit includes an innovative dual-rod altitude device that combines a stainless-steel threaded rod with a custom micro-adjustment wheel, while a belt-driven pulley system provides smooth azimuth motions. The ZLOMOTION kit enables observers to track objects at relatively high magnification at any point in the sky. Rapid motions in altitude are performed using an extendable rod and locking knob visible at the lower end of the altitude attachment. Specify your telescope make and model when placing your order. Chattanooga Millworks, 3107 East 44th St., Chattanooga, TN 37407 423-867-9911; www.chattmill.com New Product Showcase is a reader service featuring innovative equipment and software of interest to amateur astronomers. The descriptions are based largely on information sup- plied by the manufacturers or distributors. Sky & Telescope assumes no responsibility for the accuracy of vendors’ statements. For further information, contact the manufacturer or distributor. Announcements should be sent to [email protected]. Not all announcements can be listed. 42 October 2014 SKY & telescope A ide e b 3( OBSERVING Sky at a Glancé Using the Map Go out within an hour of a time OCTOBER 2014 listed to the right. Turn the map Sept 21 DAWN: The zodiacal light is visible 120 to 80 around so the yellow label for the direction you're facing is at the - Oct 6 minutes before sunrise from dark locations at mid- bottom. That's the horizon. Above northern latitudes. Look east for a huge, tall pyramid it are the constellations in front of of light stretching up through Jupiter. you. The center of the map is overhead. Ignore the parts V Oct 8 A TOTAL LUNAR ECLIPSE is visible in the predawn of the map above horizons or dawn over North America, and at other times of you're not facing. night in the Pacific and eastern Asia. See page 50. EXACT FOR LATITUDE 40° NO RTH. 17, 18 DAWN: The Moon shines upper right of Jupiter on the 17th and lower right of Jupiter on the 18th. ■oN0 ' 19 NIGHTFALL: Comet C/2013 A1 Siding Spring .____ \ passes very close to Mars; see page 53. s !J e l ° d jr 20-22 PREDAW N: The modest Orionid meteor shower •w is active shortly before dawn’s first light. Oct 20 DAWN: The zodiacal light is again visible before - Nov 4 sunrise, as described above. 0,^ 0 22 DAWN: Binoculars may show Mercury below the Sn 3 H d 3 D ^ • 2 ^ thin crescent Moon very low in the east a half hour • p * # before sunrise. * 23 A PARTIAL SOLAR ECLIPSE is visible over most z 1 0 of North America; see page 52. ■ 1 § * L A / 25 DUSK: Saturn floats a few degrees to the lower •n C u '— " f i i / E "M 3 ! right of the thin crescent Moon low in the west- i 0 R southwest a half hour after sunset. The Moon V T SS Zenith A occults Saturn during daylight in easternmost w • / 0 •f Canada and during dusk in parts of Europe. / 0 w. S w -tP O 2 27, 28 DUSK: The waxing crescent Moon shines to the -0 «■* • T Sx right of Mars on the 27th (as seen from North / A - C — v/> America) and above Mars on the 28th. __ c * / ^ * 0 Planet Visibility SHOWN FOR LATITUDE 40° NORTH AT MID-MONTH M ID N IG H T S U N R IS E ► ______T Mercury Visible Oct 24 to Nov 19 Venus Visible through Oct 4 Mars SW Jupiter E Saturn SW Visible through Oct 26 Moon Phases 3 First Qtr Oct. 1 3:33 p.m. EDT # Full Oct. 8 6:51 a.m. EDT © Last Qtr Oct. 15 3:12 p.m. EDT O New Oct. 23 5:57 p.m. EDT 3 First Qtr Oct. 30 10:48 p.m. EDT * f M 30 ^ V f • O s'S 'ls 4 < ( 4 Galaxy Double star T in n riin n ra Variable star M ii \|B \ [Q t u * EE * E * II a I Open cluster Diffuse nebula 20 21 22 23 24 25 Globular cluster 25 Planetary nebula F a c i n ] I S u p e j Gary Seronik W hen Binocular Highlight Late Aug. Midnight* Early Sept. 11 p.m.* The North America Nebula Late Sept. 10 p.m.* For observers at mid-northern latitudes, Cygnus is one Early Oct. 9 p.m.* of the most familiar constellations. Not only is it visible Late Oct. Nightfall ■ \ ^ UULEUS a *... • . • 7000 . . ’xn'' . • * • • • i • •• * ^ 6 • North America '• Nebula '• Moon * -20° CAPRICORNUS M29 CYGNUS South SkyandTelescope.com October 2014 OBSERVING Planetary Almanac Mercury Sun and Planets, October 2014 October Right Ascension Declination Elongation Magnitude Diameter I llum ination Distance ) * 1 12h 27.7m -3° 00' -26.8 31' 57" 1.001 Sun — — Oct 1 11 21 31 31 14h 19.7m -13° 56' — -26.8 32' 13" — 0.993 Venus Mercury 1 13h 51.8m -15° 15' 24° Ev +0.3 8.1" 39% 0.825 11 13h 45.6m -14° 09' 13° Ev +2.4 9.8" 10% 0.684 21 13h 08.9m -7° 24' 9° Mo +3.0 9.5" 6% 0.707 16 31 13h 12.7m -5° 30' 19° Mo -0.5 7.1" 50% 0.944 12h 06.7m Mars Venus 1 +0° 50' 6° Mo -3.9 9.8" 99% 1.706 11 12h 52.5m -4° 11' 4° Mo -4.0 9.7" 100% 1.713 21 13h 38.8m -9° 04' 2° Mo — 9.7" 100% 1.717 16 31 14h 26.5m -13° 37' 2° Ev -4.0 9.7" 100% 1.715 Jupiter O E 6 -23 ° < Mars 1 16h 38.9m 3 3 +0.8 6.1" 89% 1.535 16 17h 25.5m -24° 43' 60° Ev +0.9 5.8" 89% 1.610 31 18h 14.0m -24° 54' 56° Ev +0.9 5.6" 90% 1.682 Jupiter 1 9h 13.4m + 16° 38' 52° Mo -1.9 33.7" 99% 5.850 31 9h 30.8m +15°22' 77° Mo -2.1 36.3" 99% 5.431 Saturn 1 15h 13.7m -15° 54' 43° Ev +0.6 15.6" 100% 10.649 31 15h 26.7m -16° 47' 16° Ev +0.5 15.3" 100% 10.892 Saturn Uranus 16 0h 52.5m +4° 52' 172° Ev +5.7 3.7" 100% 19.026 Neptune 16 22h 27.9m -10° 26' 133° Ev +7.8 2.3" 100% 29.288 -20 18h 46.7m 0 ° Pluto 16 3 79° Ev +14.2 0.1 " 100% 32.926 The table above gives each object’s right ascension and declination (equinox 2000.0) at 0h Universal Time on selected dates, and its elongation from the Sun in the morning (Mo) or evening (Ev) sky. Next are the visual magnitude and Uranus equatorial diameter. (Saturn’s ring extent is 2.27 times its equatorial diameter.) Last are the percentage of a planet’s disk m illuminated by the Sun and the distance from Earth in astronomical units. (Based on the mean Earth-Sun distance, 1 a.u. Neptune is 149,597,871 kilometers, or 92,955,807 international miles.) For other dates, see SkyandTelescope.com/almanac. Planet disks at left have south up, to match the view in many telescopes. Blue ticks indicate the pole currently tilted Pluto 10" toward Earth. The Sun and planets are positioned for mid-October; the colored arrows show the motion of each during the month. The Moon is plotted for evening dates in the Americas when it’s waxing (right side illuminated) or full, and for morning dates when it’s waning (left side). “Local time of transit” tells when (in Local Mean Time) objects cross the meridian — that is, when they appear due south and at their highest — at mid-month. Transits occur an hour later on the 1st, and an hour earlier at month’s end. 46 October 2014 sky & telescope OBSERVING Fred Schaaf welcomes your Northern Hemisphere's Sky comments at [email protected]. Fred Schaaf Doubling Up in Cygnus The celestial Swan boasts some of the sky’s best double stars. The trees are in their autumn beauty, naked eyes, as described on page 66 of last month’s issue) The woodland paths are dry, show the 4.8-magnitude star 30 Cygni 338" northwest Under the October twilight the water of Omicron1. I have seen 30 Cygni as delicately green, a Mirrors a still sky; handsome contrast to nearby golden Omicron1 and more Upon the brimming water among the stones distant, vividly orange, Omicron2. Are nine-and-fifty swans. But that’s not all. A 7.0-magnitude star shines 107" south of Omicron1. Some observers say it is blue, but I But now they drift on the still water, have observed it as distinctly purple. See what you think! Mysterious, beautiful; Pairing 61 Cygni with 16 Cygni. A double star in Among what rushes will they build, Cygnus perhaps as famous as Albireo is 61 Cygni, Piazzi’s By what lake's edge or pool Flying Star, which is discussed at length on page 50 of Delight men’s eyes when I awake some day the August issue. It’s just 11.4 light-years from the Sun — To find they have flown away? the fourth closest naked-eye star, after Alpha Centauri, — W illiam Butler Yeats, The Wild Swans at Coole Sirius, and Epsilon Eridani. (Procyon is probably slightly more distant, though the error bars in the measurements Back in the autumn o f 1992, I was treated to a p air of leave room for doubt.) Telescopes show that 61 Cygni is wild swans staying week after week at the small pond a beautiful pair of orange stars, magnitude 5.2 and 6.0, near where I live. I was hoping they’d stay long enough w h ich are curren tly 31" apart. to be on the water at moonrise just before the total lunar If you reverse the numerals of 61 Cygni, you get 16 eclipse o f Decem ber 9, 1992. M y w ish came true, and I Cygni, which turns out to be a slightly fainter, similarly was able to photograph the two as they drifted across the wide and well-matched pair. It lies near the Swan’s west full Moon’s glitter path on the water. But after that night, wing, whereas 61 Cygni is near the east wing. The yellow I never saw them again. components o f 16 C ygni shine at m agnitude 6.0 and 6.2, As Yeats said, the swans had flown away. Fortunately, and lie 39" apart. NGC 6826, the “Blinking Planetary,” at October nightfall one great swan still hangs very high shines less than V ° east of this double. ♦ in the western sky for all of us in northern lands. Its name is Cygnus, and this month we continue the explora- tion of its diversities and motions. We w ill double up on doubles, exploring two matched pairs of double stars. I Albireo and Omicron Cygni. Cygnus is home to the most famous of all strongly colored double stars — Beta Cygni, better known as Albireo. Magnifications as low as 10x can show that this star, which marks the beak of the Swan, is really a 3.1-magnitude gold star w ith a 5.1-magni- tude blue star 34" from it. Amazingly, Albireo is moving almost straight toward us — in a few m illion years its proximity w ill make it one of the brightest stars in the night sky. Albireo has competition on the opposite end of Cyg nus. Just a few degrees northwest of Deneb is a pair of stars separated by about a degree: Omicron1 and O m i Like Cygnus in the cron2 (o1 and o2) Cygni. I first discovered their marvelous night sky, swans fly secrets in the 1970s. with long, out- The two stars are a 3.8- and 4.0-magnitude pair to stretched necks. the naked eye. But binoculars and telescopes (and keen SkyandTelescope.com October 2014 47 OBSERVING Sun, Moon & Planets A Busy October for the Moon The Moon experiences one eclipse, causes another, and hides Saturn. The second eclipse season o f 2014 DUSK & SOON AFTER glides rapidly east through the stars during brings most of North America exciting Saturn begins October only about 10° the month, ending October just 2 ^ ° to the views of a total lunar eclipse and, two high in the west-southwest an hour after right o f 3rd-magnitude Lam bda (A) Sagit- weeks later, a partial solar eclipse. Only sunset for mid-northern observers. By tarii, the top of the Sagittarius Teapot. the easternmost U.S. and Canada miss out month’s end the ringed world is probably Along the way, around 18h UT on on these events. See page 50 for the lunar too low in bright twilight to spot without October 19th, faint Comet Siding Spring eclipse early on the morning of October optical aid. passes less than 100,000 m iles from M ars 8th and page 52 for the October 23rd A challenging occultation of Saturn by in space and about 2' from Mars on the sky, eclipse of the Sun. the 3.5%-lit Moon may be visible through a as described on page 53. M ars’s globe has Dusk this month features Saturn telescope around midday on October 25th dwindled to less than 6" wide. sinking very low in the west-southwest from easternmost Canada; see the article Pluto, in northeastern Sagittarius, is and Mars maintaining its modest height on page 36 about daylight observing. The highest in a dark sky at the end of evening in the southwest. Mars has a startlingly occultation should be somewhat easier for twilight, but that’s still painfully low for close encounter with Comet Siding Spring Spain and the British Isles, where it takes mid-northern viewers. See the June issue, (C/2013 A1), both in space and on the sky, place in the late afternoon, and much page 50, for a finder chart. in mid-October; see page 53. easier from France and Italy to southern Bright Jupiter rises after midnight Scandinavia, where it happens in twilight. ALL NIGHT LONG and is fairly high by dawn. Venus may Mars sets about three hours after the Uranus reaches opposition in Pisces on be visible shortly before sunrise at the Sun all month and is about 15° high an October 7th and is therefore visible all beginning of October, but it soon disap- hour after sunset for observers around night this month. By amazing coinci- pears into the Sun’s glow. And late in the 40° north latitude. The Red Planet begins dence, Uranus has a close conjunction month Mercury approaches the peak of its October at m agnitude +0.8, slightly with the Moon near the peak of October best dawn apparition of 2014 for Northern brighter than Antares, its rival in color, 8th’s total lunar eclipse — a conjunction Hemisphere observers. and only about 4° from the star. But Mars that w ill be an occultation in some Arctic regions. At magnitude 5.7, Uranus is usu- ally too faint to spot through a telescope when near the full Moon, but it should be easy when the Moon is drastically dimmed in Earth’s shadow. The 3.7"-wide blue or blue-green disk of Uranus should look especially beautiful in a telescope near the vast reddish eclipsed Moon. Neptune, in Aquarius, transits the meridian in the evening about 2^ hours before Uranus does. It shines 2.1 magni- tudes dimmer than Uranus and appears about 2fi as wide through a telescope. See page 50 of the September issue for a finder chart for both planets. LATE NIGHT TO DAWN Jupiter rises around 2:30 a.m. (daylight- saving time) at the start of October, and around 1 a.m. by the end of the month. The kingly planet brightens to magnitude -2.1, 48 October 2014 sky & telescope To see what the sky looks like at any given time and date, go to SkyandTelescope.com/skychart. Fred Schaaf Decem ber but its globe is still only a little larger than its minimum apparent diameter. Even so, Jupiter climbs high in the southeast by morning twilight, and telescopes w ill show interesting details on its cloudy face. Jupi ter crosses from Cancer into Leo around mid-month. Regulus is roughly a fist-width at arm ’s length to its east. DAWN Mercury goes through inferior conjunc- tion on October 16th and then rapidly ascends into dawn view, appearing higher in the east-southeast each morning on its way to greatest elongation on Novem ber 1st. It should become visible to the unaided eye around October 24th, shining at magnitude +1.1. In a telescope that ORBITS OF THE PLANETS morning it’s a 8.7"-tall, 19%-lit crescent. The curved arrows show each planet's movement By October 31st it has brightened fourfold, during October. The outer planets don't change to magnitude -0.5, and it’s more than 50% SUN AND MOON position enough in a month to notice at this scale. illuminated. Mercury then shines about The Sun experiences a partial eclipse on 9° high 45 minutes before sunrise, with October 23rd; see page 52. Back in the evening sky after the solar Spica about 7° to its lower right. The Moon undergoes a total eclipse eclipse, the thin waxing lunar crescent is Venus starts the month rising only while passing near or in front of Uranus just upper left of Saturn shortly after sun- V hour before the Sun, and it rises later on October 8th (see page 50). set on October 25th in the Americas, and each morning. The planet soon becomes The waning crescent Moon is to the it occults Saturn in parts of Canada and lost from view in the solar glare, passing right of Jupiter at dawn on October 17th Europe as described above. A thicker cres- through superior conjunction about 1° and below Jupiter, forming a triangle with cent passes to the right Mars on October north of the Sun on October 25th. Regulus, on the 18th. 27th and above Mars on the 28th. ♦ Dawn, Oct 17—20 Dawn, Oct 20—22 Dusk, Oct 27-29 1 hour before sunrise Moon 30 minutes before sunrise 1 hour after sunset Moon Oct 17 Denebola ^ Moon J Oct 29 Jupiter Oct 20 Moon J Oct 28 Moon Oct 18 SAGITTARIUS Moon Moon ^ Oct 21 Oct 27 Regulus Mars J Moon Y Vir Oct 19 Moon O Oct 22 . Mercury Moon (use binoculars) Oct 20 Looking Southeast, halfway up Looking East-Southeast Looking South-Southwest SkyandTelescope.com October 2014 49 OBSERVING Celestial Calendar Eclipse of a Large Moon The full Moon will be near perigee when it slides through Earth’s shadow on the morning of October 8th. A totally eclipsed Moon can be anything from bright, coppery orange to deep red-black. And even within a given eclipse there’s a lot of variation across the Moon’s face, as seen here. DENNIS DENNIS DI CICCO We're approaching the second of four total lunar shadow, the penumbra. But the shading is so weak that eclipses that come at half-year intervals this year and next: you won’t notice anything until the Moon has intruded a lunar-eclipse tetrad. A ll four can be seen from at least about halfway across the penumbra. Watch for a slight parts of North America. The one coming on the morning darkening to become apparent on the Moon’s celestial of Wednesday, October 8th, w ill be visible from nearly all eastern side. The penumbral shading becomes stronger of the Americas. Moreover the Moon, two days after peri as the minutes tick off and the Moon moves deeper in. gee, w ill be 5.3% larger in diameter than it was during The second stage is partial eclipse. This begins much the first eclipse of the tetrad last April 15th. more dramatically when the Moon’s leading (eastern) The map, diagram, and timetable on the facing page edge enters the umbra, Earth’s inner shadow, where no tell what to expect at your location and when. If you’re in direct sunlight reaches. W ith a telescope, you can watch the central or western parts of the U.S. and Canada, you’ll the edge of the umbra slowly engulfing one lunar feature see the total eclipse high in a dark sky well before sun after another, as the entire sky grows darker and darker. rise. Easterners w ill find dawn brightening and the Moon An hour or so into partial eclipse, only a final bright sinking low in the west while the eclipse is in progress — sliver of Moon remains outside the umbra. And the rest is offering particularly interesting photo opportunities. already showing an eerie reddish glow. The third stage is total eclipse, beginning when the Stages of the Eclipse last rim of Moon slips into the umbra. Although the Sun A total lunar eclipse has five stages, with different things here is completely hidden, the Moon is sure to glow some to watch at each. shade of orange or red. This red light on the Moon is The first penumbral stage begins when the Moon’s sunlight skimming and bending through Earth’s atmo- leading edge enters the pale outer fringe of Earth’s sphere: it’s the light of all the sunrises and sunsets that 50 October 2014 sky & telescope S&T ILLUSTRATIONS (2; The first is sim ply how deeply the M oon goes into the the into goes oon M the deeply how ply sim is first The black. O ther tim es it appears as bright as a fresh penny. penny. fresh a as bright as appears it es tim ther O black. dark the and hidden stand Sun the see astronaut n A would oon M moment. the on given ing any at world our ring especially near the um bra’s edge, creating a subtle mix subtle a creating edge, bra’s um the near especially black. ost alm or gray, haze, ashen red, global in dark th be has ith ill w w eruption eclipse stratosphere the the the volcanic clear, ajor m polluted a f very i is recently But air the f I bright. is line. eclipse edges sunrise-sunset its the than along darker uch m is center bra’s um the bra; um ozone-rich upper atmosphere can also add to the scene, scene, the to add also can atmosphere upper ozone-rich Earth ringed w ith sunset- and sunrise-colored brilliance. sunrise-colored and sunset- ith w ringed Earth Som etim es it turns brown like m ilk chocolate. ilk m like brown turns it es etim Som The other factor is the state o f E a rth ’s atmosphere atmosphere ’s rth a E f o state the is factor other The brightness. and color eclipse’s an affect factors Two O n rare occasions the eclipsed M oon does go alm ost ost alm go does oon M eclipsed the occasions rare n O In addition, blue lig h t refracted by Ea rth ’s clear, clear, ’s rth Ea by refracted t h lig blue addition, In South North Total Eclipse of theMoon Morning of October 8 w ill appear only about 1° from the M oon during totality. totality. during oon M the from 1° about only appear ill w ness slowly fades away, leaving the M oon as bright as ever. as bright as duski- oon l a M fin the is h T leaving five. away, stage fades for slowly left is ness shading bral penum again. into eclipse re-emerges edge leading oon’s M The order. reverse line sunrise-sunset turns. the Earth around as effects cloud-shadowing sunlight, ending totality and beginning stage four: p artial artial p four: stage beginning and totality in ending replay events sunlight, orbit, its along eastward continues oon M changing by caused bra, um large the show in ay m shadows” videos flying “ Time-lapse colors. f changing o B y quite a coincidence the planet U ranus, m agnitude 5.7, agnitude m ranus, U planet the coincidence a quite y B Spot it w ith your telescope or binoculars using the chart the using binoculars or telescope your ith w it Spot Too! Uranus W h e n all o f the M oon escapes the um bra, only the last, last, the only bra, um the escapes oon M f the o all n e h W the as then, d n A inutes. m 59 lasts e tim this Totality oa cis ns72 ..62 ..52 ..4:24 a.m. 5:24 a.m. 6:24 a.m. 7:24a.m. 3:25a.m. ends eclipse Total 4:25a.m. 5:25a.m. 6:25a.m. begins eclipse Total i-cis :5am :5am :5am 3:55a.m. 4:55a.m. 5:55a.m. 6:55a.m. PDT MDT Mid-eclipse CDT EDT Eclipse event Penumbra last visible? last Penumbra ends eclipse Partial 2:15a.m. 3:15a.m. 4:15a.m. 5:15 1:45a.m. a.m. 2:45a.m. 3:45begins a.m. eclipse Partial 4:45a.m. visible? first Penumbra Total Eclipse of Moon of the Eclipse Total SkyandTelescope.com SkyandTelescope.com October October — — — Sunrises or sets eclipse moonset or sitehorizon. This timeon the oppo- at almost the same aneclipsed Moon eclipse.Because any stage of the or rise during tion, see if the bright sky. means alunar- is always full,the happens ina moonrise always Moon willset For your loca- 8 :4am :4am 5:34 a.m. 6:34a.m. 7:34 a.m. , 2014 October2014 :5am 6:05a.m. 7:05a.m. 51 OBSERVING Celestial Calendar below. The actual position of the eclipsed North America at the start of totality, but of the Moon. Identify Uranus by the Moon on the starry background in Pisces elsewhere the difference won’t be more than shape of the triangle it makes with those w ill depend slightly on where you are and a couple of Moon diameters at most. You two stars. the stage of the eclipse. On the chart, should have no trouble finding 4^-magni- Can you see anything of Uranus’s the Moon is positioned for the middle of tude Epsilon (e) and Delta (5) Piscium north aquamarine blue-green tint? Contrast with the vivid orange-red Moon may Spot 5.7-mag- make this color a little more apparent. nitude Uranus In a telescope Uranus is a tiny disk 3.7 near the Moon arcseconds wide. It ’s 2.6 light-hours using this chart from Earth, compared to the Moon’s 1.2 of Uranus’s light-seconds. position among the stars. The Moon’s position And a Selenelion? may vary a bit; If you’re in central or eastern North it’s plotted here America, the Moon w ill still be at least for an observer partially eclipsed when it sets in the in the middle of west and the Sun rises in the east. For North America most of the East Coast, this happens at the start of during totality. Meteorologist Joe Rao totality. points out that this eclipse presents an unusual chance to try seeing a selenelion: when the Sun and eclipsed Moon are October’s Partial Solar Eclipse On the afternoon of October 23rd, two map. In the American and Canadian West, Things to Look For weeks after the Moon passes through the entire eclipse happens while the Sun • Can you see any sunspots? Watch Earth’s shadow, the Moon w ill cast some is still fairly high in the afternoon sky. In the Moon’s edge creep up to them! By of its own shadow onto Earth. most of the eastern half of the continent, com paring them to the M oon’s black- Nowhere w ill this eclipse of the Sun the eclipse w ill still be in progress at sunset ness, can you see that sunspots are not be total. But as the map at right shows, — offering dramatic photo opportunities if actually black, just darker than their the Sun w ill become partially eclipsed for you can find a low western horizon. Along surroundings? North America and Mexico. a line running from the Florida Panhandle • Look for irregularities on the edge of You’ll need a safe solar filter designed through Michigan and the Hudson Bay, the the Moon’s silhouette. These are moun- for Sun viewing if you want to look at the Sun sets right when the eclipse reaches its tains seen in profile on the Moon’s limb. Sun directly, either with or without other maximum depth. • As the eclipse progresses, look around optical aid. Staring at the bright Sun East of that line, the Sun w ill set after the at the landscape and the blue sky. Has without a safely designed filter can per- partial eclipse begins but before it reaches the blue become deeper and purer? You manently damage your vision. Another m axim um . M aine and the M aritim e prov- may be surprised by how much sunlight option is to project a sharp image of the inces miss out altogether. has to be lost before anything looks dif- Sun onto a piece of paper with binoculars The farther north you are, the deeper the ferent, due to how well our eyes adapt to or a small telescope; you watch the paper. partial eclipse w ill become. In San Diego, changing lighting conditions. Or you can try pinhole projection, though for instance, the Moon’s silhouette will • Look for dim dapples of sunlight on the this gives an image of the Sun that’s very reach 43% of the way across the Sun’s disk ground under leafy trees. During a partial small and dim. For more about viewing at mid-eclipse (3:32 p.m. Pacific Daylight eclipse, random pinhole projectors form and photographing the partially eclipsed Time). In Vancouver the silhouette w ill among leaves and branches, and each Sun safely, see skypub.com/observing/ extend 66% o f the way across (at 2:57 p.m. dapple-image of the Sun’s disk w ill have celestial-objects-to-watch/eclipses. PDT). For precise local times for many cities an identical dent. Or make little holes For this event, the farther west and and towns, and more about the eclipse, see between the fingers of your two hands north you are the better, as shown on the eclipse.gsfc.nasa.gov/OH/OH2014.html. laid across each other at right angles, and 52 October 2014 sky & telescope both above the horizon at once. For most eastern cities, sunrise w ill occur a good 5 minutes before moonset. This is possible for three reasons: it’s the center of the umbra that’s exactly opposite the Sun, and the Moon is not quite there. Moonset and sunrise refer to the top edges of the Moon and Sun, not their centers. And atmospheric refraction at the horizon lifts the apparent position of all celestial objects there by 0.6°. O f course you’ll need true, flat hori- zons both to your east and west. An even trickier problem w ill be the bright sky. Bradley Schaefer, who made a study of the low Moon’s visibility, reported in the A ugust 1989 Sky & Telescope that even an uneclipsed full Moon is only visible when Sometimes other planets get all the good it is at least 2° above the horizon and the stuff! On October 19th, Comet C/2013 A1 (Sid 20:32 Sun is at least 2° below the horizon. So ing Spring) will pass 16 times closer to Mars bring good optical aid, and settle for a than any known comet has ever come by Earth. partial-eclipse selenelion if that’s what you It will miss Mars by just 82,000 miles (132,000 km). The record-holder for Earth is Lexell’s Comet of 1770, which missed us by a relatively wide 1.4 million miles. look at the shadow cast by your hands. 2017, when the dark center of the Moon’s Seen from Earth, Comet Siding Spring This partial eclipse is just a warm-up. shadow w ill pass from Oregon to South should be about 9th magnitude in mid-Octo- America’s next total eclipse of the Sun Carolina. See skypub.com/observing/ ber. It will be low in the southwest at the end is only three years away, on August 21, celestial-objects-to-watch/eclipses. of twilight, but at least Mars will be an easy marker for finding the right area. Westerners can see The chart shows where to narrow in with all stages of the Octo your scope. The daily ticks are at 0:00 UT. Put ber 23rd partial solar dots on the positions of Mars and the comet eclipse. In most of for when you’ll observe, and work in from Mars North America’s east using the stars (plotted to 9th magnitude). ern half, the Sun will Expect this event to make news when the set while the eclipse time comes. The various spacecraft on and is still in progress. around Mars will attempt close-up observa- Find what time the tions, though their cameras and instruments eclipse will be deep- est at your site by were never designed for quite this purpose! interpolating between the red lines. All times are given in Pacific Daylight Time; add 1 hour to get MDT, 2 hours to get CDT, 3 hours for EDT. The blue lines show what percent of the Sun’s diameter the Moon will cover at that time. I S&T: LEAH TISCIONE SkyandTelescope.com October 2014 53 OBSERVING Celestial Calendar Phenomena of Jupiter’s Moons, October 2014 Jupiter’s Moons Oct. 1 3:56 I .Sh. I 9:10 I .Tr. E 18:07 II.Sh.I 5:16 I .Tr. I 4:56 I .Tr. I Oct. 9 2:56 I.Ec.D 20:26 11 .Tr. I 6:21 I.Sh.E 6:13 I.Sh.E 6:20 I.Oc.R 20:58 II.Sh.E 7:32 I .Tr. E 7:13 I .Tr. E 15:32 II.Sh.I 23:18 11 .Tr. E 10:22 IV.Oc.D Oct 1 Oct. 2 1:02 I.Ec.D 17:43 11 .Tr. I Oct. 17 2:11 I.Sh.I 15:17 IV.Oc.R 4:22 I.Oc.R 18:23 II.Sh.E 3:19 I .Tr. I Oct. 25 1:12 I.Ec.D 2 12:57 II.Sh.I 20:36 11 .Tr. E 4:28 I.Sh.E 1:43 III.Sh.I 14:59 11 .Tr. I Oct. 10 0:18 I.Sh.I 5:36 I .Tr. E 4:43 I.Oc.R 3 15:47 II.Sh.E 1:23 I .Tr. I 21:45 III.Sh.I 5:17 III.Sh.E 17:51 11 .Tr. E 2:34 I.Sh.E 23:18 I.Ec.D 6:33 111 .Tr. I 4 22:24 I.Sh.I 3:39 I .Tr. E Oct. 18 1:19 III.Sh.E 10:10 111 .Tr. E 23:25 I .Tr. I 17:47 III.Sh.I 2:24 111 .Tr. I 15:45 II.Ec.D 5 Európa Oct. 3 0:41 I.Sh.E 21:20 III.Sh.E 2:47 I.Oc.R 21:02 II.Oc.R 1:42 I .Tr. E 21:24 I.Ec.D 6:01 111 .Tr. E 22:33 I.Sh.I 13:48 III.Sh.I 22:12 111 .Tr. I 13:11 II.Ec.D 6 23:44 I .Tr. I 17:21 III.Sh.E 18:23 II.Oc.R Oct. 11 0:50 I.Oc.R Oct. 26 0:49 I.Sh.E 17:57 111 .Tr. I 1:49 111 .Tr. E 20:40 I.Sh.I 2:01 I .Tr. E 7 19:31 I.Ec.D 10:37 II.Ec.D 21:49 I .Tr. I 19:40 I.Ec.D 21:33 111 .Tr. E 15:42 II.Oc.R 22:56 I.Sh.E 23:12 I.Oc.R 8 22:52 I.Oc.R 18:46 I.Sh.I Oct. 19 0:05 I .Tr. E Oct. 27 10:00 II.Sh.I Oct. 4 8:03 II.Ec.D 19:52 I .Tr. I 17:46 I.Ec.D 12:27 11 .Tr. I 9 13:00 II.Oc.R 21:03 I.Sh.E 21:16 I.Oc.R 12:51 II.Sh.E 16:53 I.Sh.I 22:09 I .Tr. E Oct. 20 7:25 II.Sh.I 15:20 11 .Tr. E 10 17:55 I .Tr. I Oct. 12 15:53 I.Ec.D 9:46 11 .Tr. I 17:01 I.Sh.I 19:09 I.Sh.E 19:19 I.Oc.R 10:15 II.Sh.E 18:13 I .Tr. I 20:11 I .Tr. E Oct. 13 4:49 II.Sh.I 12:39 11 .Tr. E Ganymede 19:18 I.Sh.E Oct. 5 13:59 I.Ec.D 7:04 11 .Tr. I 15:08 I.Sh.I 20:30 I .Tr. E 12 17:21 I.Oc.R 7:40 II.Sh.E 16:18 I .Tr. I Oct. 28 14:08 I.Ec.D Oct. 6 2:14 II.Sh.I 9:57 11 .Tr. E 17:24 I.Sh.E 15:34 III.Ec.D 13 4:21 11 .Tr. I 13:15 I.Sh.I 18:34 I .Tr. E 5:05 II.Sh.E 14:21 I .Tr. I Oct. 21 11:36 III.Ec.D 17:41 I.Oc.R 19:12 III.Ec.R 14 7:13 11 .Tr. E 15:31 I.Sh.E 12:15 I.Ec.D 11:21 I.Sh.I 16:38 I .Tr. E 15:13 III.Ec.R 20:34 III.Oc.D 12:24 I .Tr. I 15:45 I.Oc.R Oct. 29 0:14 III.Oc.R 15 Oct. 14 7:38 III.Ec.D 13:38 I.Sh.E 10:21 I.Ec.D 16:26 III.Oc.D 5:02 II.Ec.D 14:41 I .Tr. E 11:15 III.Ec.R 20:06 III.Oc.R 10:21 II.Oc.R 16 Oct. 7 3:40 III.Ec.D 12:15 III.Oc.D Oct. 22 2:28 II.Ec.D 11:30 I.Sh.I Callisto 4:51 IV.Ec.D 13:48 I.Oc.R 7:43 II.Oc.R 12:42 I .Tr. I 17 7:16 III.Ec.R 15:54 111 .Oc. R 9:36 I.Sh.I 13:46 I.Sh.E 8:01 III.Oc.D 23:54 II.Ec.D 10:47 I .Tr. I 14:58 I .Tr. E 18 8:28 I.Ec.D Oct. 15 5:03 II.Oc.R 11:53 I.Sh.E Oct. 30 8:37 I.Ec.D 9:39 IV.Ec.R 7:43 I.Sh.I 13:03 I .Tr. E 12:10 I.Oc.R 19 11:40 111 .Oc. R 8:50 I .Tr. I Oct. 23 6:43 I.Ec.D 23:18 II.Sh.I 11:51 I.Oc.R 9:59 I.Sh.E 10:14 I.Oc.R Oct. 31 1:47 11 .Tr. I 15:07 IV.Oc.D 11:07 I .Tr. E 20:43 II.Sh.I 20 2:09 II.Sh.E 20:01 IV.Oc.R 15:26 IV.Sh.I 22:51 IV.Ec.D 4:40 11 .Tr. E 21:20 II.Ec.D 20:09 IV.Sh.E 23:07 11 .Tr. I 21 5:58 I.Sh.I Oct. 8 2:22 II.Oc.R 23:33 II.Sh.E Oct. 16 2:09 IV.Tr.I 7:11 I .Tr. I 5:50 I.Sh.I 4:50 I.Ec.D Oct. 24 2:00 11 .Tr. E 22 8:14 I.Sh.E 6:53 I .Tr. I 6:57 IV.Tr.E 3:41 IV.Ec.R 9:27 I .Tr. E 8:06 8:17 4:05 23 I.Sh.E I.Oc.R I.Sh.I Every day, interesting events happen between Jupiter’s satellites and the planet’s disk or shadow. The first columns give the date and mid- 24 time of the event, in Universal Time (which is 4 hours ahead of Eastern Daylight Time). Next is the satellite involved: I for Io, II Europa, III Ganymede, or IV Callisto. Next is the type of event: Oc for an occultation of the satellite behind Jupiter’s limb, Ec for an eclipse by Jupiter’s 25 shadow, Tr for a transit across the planet’s face, or Sh for the satellite casting its own shadow onto Jupiter. An occultation or eclipse begins when the satellite disappears (D) and ends when it reappears (R). A transit or shadow passage begins at ingress (I) and ends at egress (E). 26 Each event is gradual, taking up to several minutes. Predictions courtesy IMCCE / Paris Observatory. 27 O cto b e r 1, 0:31, 10:27, 20:22; 2, 6:18, 16:14; 3, 28 A ctio n a t Jupiter 2:10, 12:05, 22:01; 4, 7:57, 17:53; 5, 3:48, 13:44, 29 Jupiter shines very high before the late- 23:40; 6, 9 :36 , 19:31; 7, 5:27, 15:23; 8, 1:19, 11:14, arriving dawns of October, but it’s still only 21:10; 9, 7:06, 17:01; 10, 2:57, 12:53, 22:49; 11, 30 34 to 36 arcseconds wide. 8:44, 18:40; 12, 4:36, 14:32; 13, 0:27, 10:23, 20:19; 31 Any telescope shows Jupiter’s four big 14, 6:15, 16:10; 15, 2:06, 12:02, 21:58; 16, 7:53, moons. Identify them using the diagram 17:49; 17, 3:45, 13:40, 23:36; 18, 9:32, 19:28; 19, at left. Interactions between Jupiter and its 5:23, 15:19; 20, 1:15, 11:10, 21:06; 21, 7:02, 16:58; The wavy lines represent Jupiter's four big satellites. The central satellites are listed above. 22, 2:53, 12:49, 22:45; 23, 8:40, 18:36; 24, 4:32, vertical band is Jupiter itself. Each gray or black horizontal band is And here are the Universal dates and 14:28; 25, 0:23, 10:19, 20:15; 26, 6:10, 16:06; 27, one day, from 0h (upper edge of band) to 24h UT (GMT). UT dates 2:02, 11:58, 21:53; 28, 7:49, 17:45; 29, 3:40, 13:36, are at left. Slide a paper's edge down to your date and time, and times when the Great Red Spot should read across to see the satellites' positions east or west of Jupiter. cross Jupiter’s central meridian: 23:32; 30, 9:28, 19:23; 31, 5:19, 15:15. ♦ 54 October 2014 sky & telescope At your command Powerful telescope control built in Smooth panning and zooming using ^ OpenGL graphics acceleration Access the latest and most accurate astronomical catalogs Tailor the user interface to your workflow Optional Camera Add On provides native camera control, autoguiding, automated focus and more f Plan observing sessions using i simple or complex database queries Perform fast, reliable astrometric solutions (a.k.a. “ plate solves”) Optional TPoint Add On improves telescope’s pointing accuracy, aids polar alignment and more Optional automated image acquisition and pointing calibration Available for Mac and Windows (sold separately) TheSkyX Professional - Put Your O bservatory on the Map SOFT FIND YOUR SPACE BISQUE.COM BISQUE Mark your calendars! October 11, 2014 ' siaexpo.com OBSERVING 56 xlrn h Moon Exploringthe October 2014 S&T: SEAN WALKER (2; w h ile most nights it ’s sufficiently far away for the high- high- the for away far sufficiently ’s it nights most ile h w looks who Anyone land terrain beyond to be easily visible. The M oon’s rock oon’s M as n The know is visible. otion easily m be to ing beyond 1st), terrain October land on to appears it (as f o b lim shores to the eastern touch respect the ith es w nearly etim Som positions eir b. th lim the change to appear features through its orbit controls w h ich parts o f the lim b we can can we b lim f the o parts ich movement h w oon’s M the controls orbit its Instead, through bobbing. and g tiltin cally ones. nearside some hiding and features see. The M oon rotates at a constant velocity around its around velocity constant a at rotates oon M The see. farside revealing alternately b, lim the along f features o Set your sights on the ever-changing lunar limb. lunar ever-changing the on sights your Set okn n Rolling and Rocking Librations are are Librations tel e p o c s le e t & y k s not at the M oon regularly notices that that notices regularly oon M the at caused by the M oon its e lf physi- physi- lf e its oon M the by caused libration adi hne u iw view our changes it and Mare Crisium Mare west lim bs by as m uch as 7.7°. Thus we can periodically periodically can we Thus 7.7°. as uch m as by bs lim west polar axis is slightly in clined to its orbital plane, it is tilted tilted is it plane, orbital its to oon’s M the clined in Because slightly is regions. axis polar polar f its o views proved im terrestrial in result velocity f plane- in o Law changes Second These epler’s K otion. m ith tary w slows ent accordance ovem in m closest orbital its f its , o Earth because but around orbit length), tical f constant llip o e is day (its axis polar so that p eriodically we see as far as 6.7° beyond its poles. its beyond 6.7° as far as see we eriodically p that so visible. ally rm no not features equatorial and farside east some ar see n lu the around peek to able being observers when up speeds and rth Ea from farthest is it when down tidfco steMons itnefo at.When W Earth. from distance oon’s M the is factor third A us gives otion m oon’s M f the o aspect second A fromthe lunar limb ference of perspective thenear left, we see during arare extreme crater is well seen far craterEndymion doesn’t repeat for different angle that everynight we see the image). At far left, the negative”“ libration. lunar surface during a prominently above the its outer rimprojecting libration, whereas at images of the flooded between these two (center inthe far left more than18 years. Moon froma slightly Due tolunar libration, Note the extreme dif- Contributing editor Charles A. Wood ne ver consults a libration chart, preferring to be surprised at what chance bestows on him. Charles A. Wood October 6, 10h UT diam. 32' 58" October 18, 6h UT diam. 29' 31" Librations Wilson (crater) October 5 FIRST QUARTER October 31, 2:48 UT Lyot (crater) October 7 Neper (crater) October 9 For key dates, black dots on the map indicate what part of the Moon’s limb is Desargues (crater) October 20 tipped the most toward Earth by libration under favorable illumination. S&T: DENNIS DI CICCC the Moon is at apogee — its farthest point from Earth — If you follow librations for a few lunations you’ll notice we can see slightly farther around its entire limb than that the librated limb migrates all the way around the when it is closest at perigee. You can demonstrate this for edge of the Moon each month. That cycle continues, with yourself: hold an orange about 6 inches in front of your greater or lesser degrees of tilt, every night afterwards, nose and then at arm’s length. You’ll see farther around forever. Because of the interplay of all the different com- the circumference when it’s at arm’s length. ponents of libration, it takes one saros cycle of 18 years, 11 Because the total libration of the Moon depends on a days, and 8 hours before the exact libration and light- combination of all of these physical factors (and others), ing repeats. This means that every time you observe the calculating the libration zone was quite difficult before Moon, you see essentially a slightly different view. the advent of electronic computers. Today, a variety of When observing the Moon, S&T imaging editor software programs can do it, and each issue of Sky & Sean Walker suggests that librations provide two areas Telescope includes a map that pinpoints the best libra- to observe. Although the positive liberated areas reveal tion areas throughout the month and notes interesting Earthward tilted views of those limbs, the opposite limb features to observe (see above). is worth looking at too. Craters on that limb appear more This month there are no extreme librations visible in profile than how we usually see them. On the evening on the illuminated limb. The strongest libration starts o f October 5th, w h ile the libration zone is in the south- on October 5th along the south-southwest limb near the southwest limb near Wilson, the opposite limb around the crater Wilson. The best libration then migrates eastward north polar area is tilted away from Earth, giving a profile to the southeast limb near Lyot two nights later, and con- view of craters such as Scoresby and Anaxagoras. tinues to Neper on October 9th. By October 20th the part Looking at craters under “negative” libration reveals of the Moon with maximum tilt toward Earth is near the that crater rims are relatively low, compared with the crater Desargues, just west of the lunar North Pole. great depths of their floors. You can experience this Unfortunately, the areas best tilted into view are effect closer to home if you ever have a chance to visit not always visible. On the 5th the librated limb lies in Meteor Crater in northern Arizona. As you approach the shadow and thus is not observable. Similarly, on the 20th, site from a distance, the crater rim appears to be a low although the region of Desargues is illuminated, it’s near plateau, with no hint that it’s really the mountainous edge the sunset terminator and you can see very little at the tip of an amazing hole. of the thin lunar crescent. This month’s examples of libra- Librations, both positive and negative, reveal lunar fea- tion are pretty typical, and the frustrations that librations tures in a new light and help you understand limb craters can provide remind me of the title of one of Robert A. in 3-dimensional space. Such changing perspectives make Heinlein’s best novels: The Moon Is a Harsh Mistress. observing the Moon endlessly fascinating and new. ♦ SkyandTelescope.com October 2014 57 OBSERVING Deep-Sky Wonders Darkness and Light Cygnus is replete with wonders, both bright and dark. In 1749, the French astronomer Guillaume Le Gentil Binoculars also reveal the open cluster Messier 39, described a remarkable object behind the tail of Cygnus: just east of where Le Gentil 3 dissolves into streamers, “It seems of a different nature from all nebulae observed encompassing 16 stars within its hallmark triangular before and from the M ilky Way, which it crosses at nearly shape. Through a telescope, M39 shows best at a mag- a right angle. It’s a large cloud, wider at one end than nification that frames it with a generous amount of the other, the narrower end toward the southeast. This surrounding sky. Through my 130-mm refractor at 37x, cloud is only about six degrees from the tail of Cygnus. M39 appears a little more than across with somewhat It is almost opaque and very dark. A telescope reveals a irregular borders. I count 50 stars. The brightest stars in few stars in this part of the sky, but none appear to the this fairly young cluster glitter an icy white or blue-white, unaided eye. The cloud is visible without a telescope.” while many of the fainter ones are M ilky Way backdrop. Have you ever noticed this dark nebula? Le Gentil 3 M39 is an astonishingly triangular group of bright is a striking feature when the sky is dark enough to lay stars through my 10-inch reflector at 43x. I see a few the splendor of the M ilky Way before your eyes. Training touches of color among its stars. There’s a yellow star in 10x30 binoculars on it, a wonderfully intricate study in the group’s western edge, an orange one south-southeast shadow and light unfurls. The nebula tapers and shreds of M39’s brightest star, and a golden one east of the as it crosses the M ilky Way, like black-lace curtains tat triangle’s northern point. A 9th-magnitude star along tered by age in some long-forgotten mansion of the night. the eastern side of the triangle is the prim ary of the John Le Gentil 3 is simply a cold, dark cloud of interstel- H erschel double star h1657 (H J 1657), whose 12th-mag- lar gas and dust. Without the dense star fields that it nitude companion sits 23" to the north-northeast. A few obscures, we wouldn’t be treated to this amazing inter- stars south of the triangle make a short trunk for a very play of light and dark. wide Christmas tree. 58 October 2014 sky & telescope Sue French welcomes your comments at [email protected]. Sue French Bright Objects and One Great Dark Cloud in Northeastern Cygnus I count 25 bright stars in M39 through the 10-inch, ranging from magnitude 6^ to 10, and about three times as many stars from the opulent M ilky Way background. Folks with large telescopes might like to acquire the nice little planetary nebula Kohoutek 3-82, perched 1.6° north of M39. Once spotted, I can hold it steadily in view with averted vision through my 15-inch reflector at 133x. Kohoutek 3-82 is easier to see at 216x, and I give it a very rough size estimate of 25". I can hold the planetary with direct vision with the help of a narrowband nebula filter, and an O III filter works even better. The nebula is subtly annular, and my notes say that it looks slightly oval, tipped east of north. Although the nebula isn’t quite round, images show a 16th-magnitude star off its north- northeastern rim. Could this unseen star have contrib- uted to my perception? W ith his 27-inch reflector, German amateur Uwe Glahn has been able to see this star and a sim ilarly feeble one that’s superimposed on the annulus Angular sizes and separations are from recent catalogs. Visually, an object’s size is often smaller than of Kohoutek 3-82, west-southwest of the planetary’s cen the cataloged value and varies according to the aperture and magnification of the viewing instrument. Right ascension and declination are for equinox 2000.0. ter. See the next page for Glahn’s sketch of the nebula. Star clusters abound in Cygnus. NGC 7071 and NGC 7067 rest 1.2° west-southwest of M39 and emerge as two small fuzzy patches through my 130-mm scope at 37x. NGC 7071 hovers 7' northeast of a distinctive 2.7'-tall Z outlined by several faint stars. The 9th-magnitude star northwest of the cluster shines orange. NGC 7067 sports two faint stars near its center and one that’s a little brighter on its southern edge. At 164x NGC 7071 is a 3.8'- long band of nine stars, but one of the stars in the curve at the southeastern end is hard to see. NGC 7067 shows a fourth star making an arc with the two near the center. The haze is oblong, about 2W long and half as wide. Zooming in at 234x in the 130-mm scope, NGC 7067 shows a total of nine stars. Through my 10-inch scope at 187x, NGC 7071 marshals 14 stars in a thin, wavy ribbon that’s 4.2' long, while NGC 7067 reluctantly gives up a smattering of extremely faint stars and spans 3'. Nearby, NGC 7082 is a pretty cluster residing 32' north of golden 71 Cygni. My 130-mm refractor at 48x shows about 50 moderately bright to faint stars in a 25' group with borders that are easy to lose track of amid the M ilky Way. Five of the brightest stars make a squarish figure that nearly spans the cluster. The northern and two western stars shine gold, the eastern star pale yellow, and the southern star orange. Basel 12 and Basel 13 are two of the open clusters discovered at Switzerland’s Astronomical Institute of the University of Basel, which was founded in 1874 and closed down in 2007. A lasting tribute to the Institute, this interesting cluster pair is located 1.5° southeast of yellow- orange 63 Cygni. ALAN DYER SkyandTelescope.com October 2014 59 RICHARD ROBINSON AND BEVERLY ERDMAN / ADAM BLOCK / NOAO / AURA / NSF OBSERVING Deep-SkyWonders 60 60 • . • ...... *• v October 2014 west-northwest edge, and a few arcm inutes o ff the south- south- the ff o inutes arcm few a and edge, west-northwest the Perseus A rm . The others are strung between them, between strung are outward, others The arm . rm spiral A next 12,000 the 7067, Perseus about in C the G us N The is from Spur. tour away the rion in spi-O light-years the the as cluster in n Sun, know distant our most galaxy ith f our w o along shard resides, ral-arm It tour. our in ter about stars, field the Basel from 102x, at Seen south-southeast. to ular irreg an has north-northwest It stars. f o islands any the m by ff o create set and ay W area y ilk M f o patch a like uch m looks and offthe just edge, east-northeast its on stars little by agnitude m surrounded gem orange reddish 8.5-magnitude 12 also has an irreg u lar border. It appears semi-detached semi-detached appears It border. lar u irreg an has 12also about f this o covers uch and m shape through way eir th thread that f nebulae view o dark field same the shares 13 Basel edge. southwest spanning sparkles A t 1,100 light-years, M essier 39 is the nearest star clus star nearest the is 39 essier M 1,100light-years, t A Through m y 130-mm scope at 37x, Basel 12 wears an an 12wears Basel 37x, at scope 130-mm y m Through escope p o c s le e t & y k s k 3- 82 3- k 4Vi'. i . . . * . ; .. . i • Tegopn I e a 11th- has see I grouping The 10 ' x x ' 6 ' across, and shows shows and across, ' 6 ', ru n n in g approximately approximately g in n n ru ', Above: filter at 419xat his filter through 27-inchreflector. brightest 7048 the byfar is - 2a enwt nebula3-82 a with seen as Kohoutek nebula planetary Left: article. this in discussed nebula planetary Uwe Glahn sketched the sketched Glahn Uwe German stargazer stargazer German Handsome NGC NGC Handsome 20 stars. west. The planetary stands out w ell w ith a narrowband narrowband a ith w ell w out stands planetary The west. 10th- 117x.A at better is view the but 63x, 13at Basel ith w 7071 C G N C and G N light-years, 4,700 neighbors about 12at galactic Basel and 7082 light-years, 4,000 13 at Basel ith w w eakly brighter than the rest o f the nebula, but I ’m not not ’m I but nebula, f the o rest the than brighter eakly w super- star a see this can I 213x, at hecking C ends. reflector 10-inch the at y m spots ith w brighter possible ith w nice w ith an O I I I filter, but an H-beta filter banishes it it banishes filter H-beta an but also ’ssky. filter, It the 1'. I I f about from o I O eter an diam ith a w ith nice w round is and filter south-southeastern an nebula’s and the edge, hugs star agnitude m light-years. 5,500 at anyone see these m agnificent w ings through the eyepiece eyepiece the through ings w Can ith agnificent w m these northeast-southwest. see butterfly 3' ic than anyone cosm f more o cater- beautiful a the ingspan into w a orphosing planetary etam lobes m Big side, pillar-like see. each to able from was out I that balloon structure bar-like elucidation. the er rth fu no offered scope 15-inch y M be ay m certain. ends The wide. appears as nebula one-third The and end. long 1 about southeastern the on imposed northwest, to southeast and elongated 164x, at appears It nebula 234x. at definite best a 117x, at detectable becomes 1-89 eecp? ♦ telescope? f a o H D 202654. W ith m y 130-mm refractor at 91x, Sh 1-89 Sh 91x, at refractor 130-mm y m ith W 202654. D H O u r fin a l stop is the planetary nebula nebula planetary the is stop l a fin r u O O n deep im ages, there’s m uch more to Sh 1-89 than 1-89 than Sh to more uch m there’s ages, im deep n O I noticed the planetary nebula nebula planetary the noticed I eecp. ; - - telescope. biggest her of eyepiece the barthrough central the 1-89, only see could Sharpless author but the of shape butterfly the capture images CCD , located 19' southwest o f the f the o southwest 19' located , 8 th-magnitude star dwells 3.3' west-south- west-south- 3.3' dwells star th-magnitude 6 7048 NGC th-magnitude star star th-magnitude Sharpless in the field field the in The 2015 Sky & Telescope Plan ' to O bserve Observing Calendar Combining gorgeous astrophotography and special monthly sky scenes, this calendar also highlights important sky Mysteries & /Via r ve Is 2 0 1 5 events each month, including eclipses, ;f'V meteor showers, and occultations. of the Red Plánét qcv 888-253-0230 SHOPu Observing Calendar | www.ShopatSky.com SKY . 3S RPVeALED'. The TWth u ® MYSTERY: Does the Water oo Mars ■ 5SS5KS-- ASTRONOMY RESEARCHERS // AEROSPACE ENGINEERS . the Red Plánét ACADEMIC PROGRAM DEVELOPERS // DEFENSE CONTRACTORS arj | U n t . are proud to announce enaiengineering METER CLASS TELESCOPES a t O P T Lunt Engineering in partnership with OPT now provides Meter How can we find current Class telescope systems including ground floor design and or extinct life on Mars? implementation support. • “Ground Floor” Planning/ What happened to Implementation Services g y Mars's atmosphere? • Meter Class Telescopes Scalable Up To 2 Meters . jS L \ How will humans explore • Proven Optical Designs • 4 í V / \ // . the Red Planet? With Optional Customization • Alt-Az Or EQ Fork Mounting f Systems Available II Open Source Observatory Control System These are just a few of the provoca- Current System Upgrading/ tive questions explored in this new Retrofitting Services i , special issue from the editors of Sky Cost Effective Turnkey Packages & Telescope. Loaded with spectacular Project Implementation Transparency St photos and art, Mars: Mysteries & OBSERVATORY INTEGRATIONS Marvels o f the Red Planet is a must- AND UPGRADES BY OPT... 1 read for anyone interested in our EVERYTHING BUT THE DIRT. neighboring planet, the search for extraterrestrial life, and the future of human colonization of space. o p h , Now on sale at ShopatSky.com Want to learn more? Let’s Talk. // 800.483.6287 // optcorp.com/lunt-meter-class and at leading newsstands in the U.S. and Canada. S&T Test Report A la n D y e r ALL PHOTOS COURTESY OF THE AUTHOR IF YOU HAD TO LIVE with just one telescope, what Looking Through the Esprit would it be? For me, I’d pick a 4-inch apochromatic refractor. Like other refractors in the series, the Sky-Watcher Esprit If designed right, an “apo” can serve for both visual observ- 100ED employs a triplet objective with one element made from ing and deep-sky imaging, yet it’s highly portable. We have no premium FPL53 extra-low dispersion glass for the pinnacle of shortage of such telescopes on the market. color correction. The challenge is the 100ED’s fast f/5.5 focal The latest entry is a new model in the Esprit line of refrac- tors from Sky-Watcher. The Esprit 100ED is advertised as offer- The Sky-Watcher Esprit 100ED is a fast apochromatic refractor designed ing image quality equal to refractors selling for twice the price. for imaging as well as visual use. It promises first-class performance for Indeed, it retails for $2,499, whereas most competitors w ith an affordable price. The tube collapses to a compact 46.5 centimeters sim ilar specs run $4,000 to $6,000. Too good to be true? S&T (18.3 inches) but has a generous dewcap that extends to yield a total tested a unit on loan from Sky-Watcher Canada to find out. tube length of 64.3 cm. 62 October 2014 sky & telescope ratio. Compared to slower f/7 and f/8 models, fast apos are tougher to make free of false color and other aberrations. But my testing shows that Sky-Watcher succeeded. Although the Esprit line, and the 100ED in particular, are sold as astrographs — telescopes optimized for photogra- phy — the beauty of refractors is that making them great for imaging rarely compromises them for just visual use. By comparison, optimizing reflectors for imaging usually requires oversizing the secondary mirror, which degrades visual contrast and resolution. The 100ED proved to be a superb visual instrument. Viewed at high power, stars looked “textbook perfect,” with little evidence of spherical aberration disturbing their A iry disk patterns, and there was no hint of astig- matism distorting them into ellipses or other odd shapes from malformed or pinched optics. Using Vega, racking to inside of focus revealed a trace The included 9x50 finderscope is an erect-image, right-angle of blue tint on the perimeter of the diffraction pattern, design. You can focus it by loosening the retaining ring at the front end and then turning the objective. while outside of focus the pattern showed the palest rim of magenta. But when in focus, Vega was colorless with no halo of blue or violet. This is color correction on a par the telescope’s manual, downloadable as a PDF from the with other premium fast apos I have tested over the years. Canadian Sky-Watcher site at tiny.cc/ngdvhx. U sing a 41-mm Tele Vue Panoptic eyepiece to achieve A word of caution: attaching a camera to the focuser the widest possible field with this telescope, stars looked involves three adapter rings plus the field flattener. Lose sharp across the field, distorting only slightly at the very any one ring and you’re out of business! edges. Switching to a high-power 3-mm Radian eyepiece, I Images taken with the field flattener and a full-frame tried a popular test for resolution, the “Double Double” star Canon 5D Mark II showed round stars across the field, Epsilon Lyrae. Each of its two tight pairs was cleanly split, with only very slight distortions in the extreme corners. with tiny Airy disks surrounded by a single diffraction ring This performance is as good as with any other telescope/ and clear dark sky between the component stars. Visual flattener combination I’ve used. observers w ill find little to criticize about the Esprit 100ED. The outer area of the frame was darkened slightly by vignetting, but no more so than with any fast apo in my Photographing Through the Esprit As it is sold in North America, the Esprit 100ED is sup- The f/5.5 objective plied with a two-element field flattener. This device is elements are flawlessly not a focal reducer and does not change the f/ratio. The X multicoated, and the flattener replaces the visual back and has a step-down tube has one knife-edge ring with a standard male T-thread for attaching CCD baffle halfway down the cameras. Also included is a T-ring adapter for Canon EOS tube to eliminate off-axis cameras that threads onto this step-down ring. Owners glare. The focal length as tested was 550 mm of other camera brands w ill need to supply their own (21.7 inches) — just as T-rings. Details on the adapter ring system are found in advertised. The included tube rings are each drilled with five ^-20 bolt holes on both their tops and bot- toms, making it easy to attach additional plates, rings, or other accessories. SkyandTelescope.com October 2014 63 S&T Test Report experience. The vignetting was uniform and would be easy to correct with flat-field calibration frames or, as I prefer with raw DSLR files, using Adobe Camera Raw’s lens-correction settings. Handling the Esprit The tube weighs 7.6 kg (16.8 pounds) with its field flat tener, tube rings, and dovetail plate — pretty hefty for a The solid 3-inch focuser combines a 4-inch telescope. Depending on what weight of camera helical-cut rack-and-pinion gear on the and guidescope gear you would want to add, I ’d suggest bottom and a Crayford slider on the top. at least a medium-duty mount for any astrophotography The top surface (not shown) features performed with the Esprit 100ED. In the Sky-Watcher a graduated scale for pre-setting the focuser. The little silver lever is the lock. line, the EQ 6 or A Z - EQ 6 m ounts would do the job. The generously long dewcap is secured with two locking screws, so it won’t slide back down the tube its entire field of view while wearing glasses. with a bang when aimed straight up. The supplied 9 x50 The finderscope has sturdy rings and six nylon-tipped finderscope offers decent optical quality, though stars collimation bolts, which provide solid alignment. The were distorted in the outer half of the field. Its eyepiece finder’s bracket attaches with a standard dovetail shoe provides generous eye relief, which enabled me to view secured to the main tube with a single setscrew. I was concerned this might lead to some wobble, but it proved The focuser accepts either a 2-inch visual back for solid and secure. This is important because some imagers the included star diagonal, or a field flattener with its w ill replace the 9 x50 finder with a small guidescope in 48-mm step-down ring and T-ring for a Canon DSLR. the same rings — and any looseness w ill be a problem. Focusing the Esprit Besides the objective, the telescope’s focuser is the most important element in any astrograph. The Esprit line uses what Sky-Watcher calls a “linear power” focuser, a hybrid rack-and-pinion and Crayford design. I found no wobble or image shift with heavy 2-inch eyepieces or a DSLR camera, though I did not weigh it down with massive CCD imagers, filter wheels, and robotic focusers. My impression is that the Esprit line is designed with the DSLR shooter in mind. The distance from the back of the focuser to the focal plane is 185 mm. But for the flattest field, the critical WHAT WE LIKE: Superb optical quality for visual use Flat field for photography use Excellent focuser and fittings Sturdy carrying case WHAT W E D O N’T LIKE: Awkward camera rotation Uses multiple adapter rings You can loosen the spoked silver ring to rotate the entire focuser, or rotate just the camera and field flattener by loosening the two knurled rings (arrowed). Neither method was easy, as the rings tended to bind. 64 October 2014 SKY & telescope distance to maintain is the 63-mm spacing from the back turn; or the camera and field flattener can turn by loosen- surface of the field flattener to the focal plane — optimal ing two counter-rotating lock rings at the camera end of the for the back focus required by DSLRs and their T-rings. focuser. W ith the former, it was just as easy to unscrew the CCD cameras might require a custom-made spacer ring. entire focuser from the tube. But with the latter method, I The 90 mm of focus travel provided more than often found it difficult to loosen the knurled rings. enough range to accommodate all of the dozen or so Both methods risk shifting the focus — not to men 1V4- and 2-inch eyepieces I tried. But my W illiam Optics tion bumping the telescope off target as you wrestle with binoviewer would not reach focus even with its Barlow the locked-up rings. Far preferable is a rotation mecha- lens installed and when used with a 1V4-inch diagonal. nism using large, glove-friendly setscrews, the method The focuser has an 11:1 dual-speed mechanism, which used on Sky-Watcher’s larger Esprit 120. The 100-mm proved very smooth and precise. There was enough ten- model should use the same design. sion so that even the heaviest eyepiece did not cause the As best I could determine, this shortfall was the only focuser to slip when it was unlocked and aimed straight significant price to pay for getting an astrograph that can up. Yet it was easy to make fine adjustments. The lock indeed compete with the best, but at a substantially lower lever did just that — it prevented further movement with- price. The Esp rit 100ED’s fast f/5.5 focal ratio is about two- out introducing any image or focus shift. thirds of an f/stop faster than the many f/7-class 4-inch My only issue with the Esprit 100ED’s design is how it apos on the market, and this gives you shorter exposures. handles camera rotation. You want to easily rotate a cam Overall, I recommend the Esprit 100ED as a superb era up to 180° to frame the field, switch from landscape to telescope for all-purpose observing and wide-field imag- portrait orientation, or put the camera right-side up after ing. It’s a refractor I could happily live with if I had to doing a meridian flip with a German equatorial mount. survive with just one telescope. ♦ Rotation should be quick and easy, yet it should also lock back down again with no image or focus shift. Contributing editor Alan Dyer recently retired from 40 years This setup offers two rotation points: a large “ship of producingplanetarium shows. Follow his continuing astro- wheel” ring can be loosened, enabling the entire focuser to nomical exploits andphoto blog at www.amazingsky.net. SkyandTelescope.com October 2014 65 JP Library Telescope Program Check Out This AMATEUR ASTRONOMY has seen many significant changes An innovative program over the past 30 years. One worrisome, often-discussed trend allows newcomers of all has been the declining numbers of young people taking up the hobby. Although the reasons for the dearth of young skygazers are ages to borrow compact, complex, one factor is clear: If you haven’t been exposed to a star- filled night sky, you’re far less likely to pursue amateur astronomy. high-quality reflectors from As he pondered this dilemma six years ago, Marc Stowbridge of public libraries the New Hampshire Astronomical Society (NHAS) had a “eureka moment.” He realized that many people — particularly youngsters — could be introduced to our hobby through a venue fam iliar to JOHN JARDINE GOSS nearly everybody: the local public library. Stowbridge’s idea was both simple and game-changing. In The library-telescope program is a fun way to help more youngsters December 2008, he modified a small telescope to increase its become involved in amateur astronomy. Here, patrons at Adams durability and then donated it to his hometown library. Patrons Library in Chelmsford, Massachusetts get ready to borrow a user- could then check it out just as they would a book. Anyone with friendly telescope for a full week. a fledgling interest in astronomy would have the chance to use a 66 October 2014 sky & telescope Telescope! The Perfect Library Loaner Telescope What instrument best fulfills the requirements of being highly portable, simple to use, and relatively inexpensive — while providing steady, clear views of the objects that novices want to observe? Stowbridge and other NHAS members, resisting the temptation of aperture creep, decided on Orion’s 4.5-inch StarBlast reflector. It provides plenty of aperture in a compact, portable, easy-to-use package. Then the library-telescope team opted to replace the two modest eyepieces supplied with each StarBlast in favor of a single 8-to-24-mm zoom eyepiece. It provides good eye relief and a relatively wide true field, making it easier for the uninitiated observer to locate bright sky objects. This combination provides a 2^°-wide view at low power (19x). That’s enough to fit all of the Pleiades stars, the Double Cluster, and the Orion Nebula in one wide field, each giving impressive scenes for excited eyes. At 56x, the eyepiece’s other extreme, users can pick out lunar craters and mountains, see hints of Jupiter’s cloud features, resolve Saturn’s rings, and glimpse Venus’s crescent. Making the Scope Library-Ready Any off-the-shelf telescope, even the rugged little StarBlast, needs a few modifications to withstand the rigors of unsupervised home visits — and to make it as trouble-free and easy to use as possible. Over time the NH AS library-telescope team has developed tried-and-true upgrades that have worked well. Every few months the club holds a “scope-modification party,” at which an assembly line of up to a dozen volunteers (now led by Pete Smith) turns new StarBlasts into library-ready units. Here’s a Thanks to an outreach program started by the New Hampshire Astro- recap of the most important changes they make: nomical Society, nearly 200 specially modified Orion StarBlast 4.5 • Eyepiece focuser: The zoom eyepiece can easily be dropped, telescopes are now available to library patrons across the U.S. lost, or mishandled. So it’s secured in the focuser tube with button-headed setscrews that can’t be easily removed. compact, high-quality, easy-to-use telescope in the comfort of • Collimation knobs: A novice user might be tempted to fiddle their home. with the six shiny mirror-collimation knobs at the rear of the He convinced his club to donate more scopes to libraries optical tube. So club members remove the knobs and replace throughout New Hampshire. Another 10 found homes at other them with three locknuts on short, spring-loaded screws. libraries the following year, and interest in the program soared. • Dust caps: The plastic dust caps that cover the main optical Recently, the count of NHAS-facilitated telescopes reached 100. tube and the eyepiece can, and likely will, be lost in no time. So Loaning telescopes certainly is not a new practice. Many “Can’t Lose Strings” are added to attach these caps to the scope. clubs let their members borrow modest Dobsonian reflectors or • Red-dot finder: The StarBlast sports a 1x red-dot finder. When various other types, and some groups also make these available aligned with the main tube, it’s quite sufficient for putting tar- to the public. But the NH AS concept sidesteps the complications get objects in the eyepiece view. But the factory-supplied button of lending equipment by partnering with local libraries — battery dies in a few days if the unit is left on. A much more institutions that, by design, loan things to the public. durable solution is to replace it with an external plastic case SkyandTelescope.com October 2014 67 68 68 irr eecp Program Telescope Library October 2014 JOHN JARDINE GOSS S&T: J. KELLY BEATTY S&T: J. KELLY BEATTY Above left: o h irr eso (ih) elcdb hr cesad hard-and screws byshort replaced (right), version library the for an 8-to-24-mman ( providing (5)and tube; zoomeyepiece; focusing the in setscrews adding (4) finder; dot reflec 4.5tabletop StarBlast Orion beginner-friendly make Tothe the country thanks to the library-telescope program. library-telescope the to thanks country over the all itself repeating is that scene a StarBlast, aof eyepiece the 2008.in program scope cell. to-turnlocknuts. removed They’re hands. inexperienced for temptation a screws, collimation of sets two with comes (left) StarBlast standard The tube. main the to stickers other tor even easier to use and more rugged, volunteers make several rugged, more volunteers anduse to easier even tor os at; ( parts; loose Moon’s brightness; (3) installing an AA-battery pack for the red- the packfor AA-battery an installing (3) brightness; Moon’s to Strings” Lose Can’t “ (1) adding them: among modifications, Blast’s collimation screws is to install a plastic cap over the mirror the over cap plastic a install to is screws collimation Blast’s Top right: tel e p o c s le e t & y k s Another way to keep hands away from the Orion Star- Orion the from away hands keep to way Another 2 ) cutting a cutting ) Marc Stowbridge initiated the NHAS’s library-tele- NHAS’s the initiated Stowbridge Marc Bottom right: Bottom 2 -inch hole in the end cap to reduce the reduce to cap end the in-inch hole 6 ) adding a Sun warning and warning Sun a adding ) A young boythroughgazes young A A Great Community Project Community Great A in involved been ho’ve w librarians ith w speaking r fte A strap- a and constellations, the to guide pocket Audubon’s agnification m map, oon M handy a provide labels These string. a ith w anchored again cap, plastic f all o sm a most ith block w to cap end tube’s optical the in hole wide patrons, partnering w ith “ Friends o f the Lib ra ry” groups, groups, businesses. ry” ra local Lib from f the o sponsorships Friends “ seeking library ith w and asking by partnering funds donation raise patrons, can outright you an club, the from your by bring Aside $325. about accessories to cost other total and eyepiece zoom labels. the but downloadable detailed and lists, parts instructions, including — odification need m you’ll details the the ll a make To own. initiated f their o have programs countries) other in library-telescope (and .S. U the across for except weather! — the about reported been plaints have com problems no that and a cutting is solu- A altogether lost. filter easily the be avoids could that that tion but barrel, eyepiece the sight. ent replace alignm to is notched a solution ith w nother A pointer red-dot the batteries. A A two holding the optics i f needed. Stowbridge reports that none o f the f the o none that reports cleans and Stowbridge ation, needed. collim f i adjusts telescope optics ith the the w damage, for checks loaner who rary er” lib periodically each astronom pairs foster last team “ S won’t local A a H they N — the spans So life forever. ited lim have telescopes checked ’s on it e that, tim ates each estim e telescope H a use use.” to people six their friends for average, kids’ home ent it their and bring instrum they the kids out and old, The “ years checking 40 to 30 reports, f is adults o range Stowbridge age year, a typical least at for program the National anual, m n containing ctio pack all stru sm in a 4-by-6-inch members inated attaching Club lam by a it” Sun. k “ the the discour- toward to complete telescope the arning w safety a pointing age and charts, ount. m field-of-view and and tube ain m the to labels self-adhesive nated, covered is hole The telescope. the entering oonlight m the ing. view fortable and com for gibbous reduced be to during t h needs lig f its phases o ll fu intensity the but target, startup process easier, the website nhastro.com/ltp.php has has nhastro.com/ltp.php website the easier, process startup clubs other and something, onto is S A H N the Clearly, ent istreatm m to due damaged been has telescopes S A H N common. are f patrons o lists aiting w long and — out program. lot a the depends publicize that ll, club e and W e?” rary com lib they your ill how on w it, build I f I “ s. LED red ith w equipped headlamp on into r” filte oon M “ neutral-density a screw observers any M • e aphr’ ucsfl Model Successful Hampshire’s New Aperture reduction: Aperture The library-telescope program was brought to the to brought was program library-telescope The $200, for retails ally rm no telescope 4.5 StarBlast The lami- apply volunteers changes, these aking m r fte A Like books that are heavily used by the public, these these public, the by used heavily are that books Like The M oon is a popular nighttim e e nighttim popular a is oon M The 2 -inch- attention of the Astronomical League in 2011 by members of the Astronomy Enthusiasts of Lancaster County in Pennsylvania. They had learned about it from the January 2011 Focal Point in S&T written by NHAS members. Since then, the League has been promoting the LTP to its member clubs. The March and June 2013 issues of its publication, The Reflector, were largely devoted to youth in astronomy, and one article featured the NHAS program. The Southern Maine Astronomers have placed 30 telescopes in area libraries. “It’s been a great outreach program for the SM A,” says club officer Ron Thompson. “We have a number of members who volunteer their time as mentors to the libraries.” Both SMA and NHAS work Nia Shea Ashby, Zeth Ashby, and their mother Karson Ashby with Maine’s Cornerstones of Science, a nonprofit group learn how to use a NHAS loaner telescope. that procures the telescopes at discounted prices. Michigan has at least two astronomy groups actively in progress, and the LTP has undergone many involved. The University Lowbrow Astronomers has improvements since its introduction six years ago. The placed 30 telescopes with the Ann Arbor Public Library, New Hampshire Astronomical Society wants to hear and the Kalamazoo Astronomical Society has donated from other clubs taking up the cause and to learn about four. Mike Cook, who heads the Kalamazoo effort, different modifications that have been made to the explains, “This program w ill give us the avenue to telescopes. Contact Pete Smith or the club at nhastro. reach many who have never had the opportunity to look com/contact.php. Club officers interested in obtaining through a good telescope.” StarBlast telescopes for their own program should send Naturally, clubs want to avoid any mishaps with their an e-mail to [email protected]. first foray into the program. “Before we presented the first W ill all this effort increase interest in amateur telescope to the library, we field-tested both the telescope astronomy? W ill it cause more young people to become and the concept of loaning it by allowing a local scout stargazers and join astronomy clubs? No one knows, troop to use it, with guidance from us. Several scouts because it might take years before any lasting effects earned their Astronomy Merit Badges as a result,” explains are evident. Nevertheless, the library-telescope program Dave Koren of the Kiski Astronomers in Pennsylvania. is having a positive impact on communities across the The library-telescope program is a work continually country right now. It’s the perfect outreach project. ♦ A year ago, this team of NHAS volunteers modified and readied A lunar observer and member ofthe Roanoke Valley Astro- 10 StarBlasts for delivery to libraries throughout New Hamp- nomical Society, John Goss was recently elected to serve a shire. The club has now distributed 100 telescopes statewide. two-year term as president ofthe Astronomical League. NHAS SkyandTelescope.com October 2014 6 9 TelescopeWorkshop Gary Seronik Gary ALL PHOTOS COURTESY OF JIM CHUNG focuser of his 12-inch Cassegrain telescope. This handy device enables him tohim enables device handy This 12-inchhis telescope. of focuser Cassegrain thein mounted here shown turret eyepiece inexpensive made the Chung Jim quickly and easily change the scope’s magnification. scope’s the change easily and quickly 70 October2014 H e v a view s o f an object at different m agnifications. T h is device device is h T agnifications. m different at object f an o s view agnification. m telescopeS your change you when dark the in bling fum Avoid oeta ha unh”acrigt Chung. to according nch,” lu Best cheap a than seconds. in more in tra hich f w o optical one the any into — switched eyepieces be five to can up holds that eyepieces. turret different evaluate to easier uch m it compare makes also quickly also can One to eager adaptation. change observers dark you hen deep-sky w to preserve appeal ill flashlight a w use to eyepieces having Not one. turret. build eyepiece an likely: less disaster dark. the in potential ground f an the o g sound hittin f gear o heart-stopping piece the ith w expensive r ilia fam sadly are o f all, they’re easy and inexpensive to make, costing “ no no “ costing make, to inexpensive and easy they’re f all, o f us o any M focuser? scope’s f your o out it swapping Fortunately, you can build a device that w ill make this this make ill w that device a build can you Fortunately, urtEeic Holder Eyepiece Turret A Toronto, O ntario, A T M Jim Chung has b u ilt a n ifty ifty n a ilt u b has Chung Jim M T A ntario, O Toronto, But preventing heart attacks isn ’t the only reason to reason only the ’t isn attacks heart preventing But escope p o c s le e t & y k s u o y r e v e rpe neeic ile h w eyepiece an dropped The holders had earlier been d rilled and tapped to accept accept to tapped and rilled d been earlier had holders The eyepieces. f the o one to hole a through t ligh feeds ich h w a stationary body that attaches to the telescope’s focuser. focuser. telescope’s and the to holders, attaches ain that eyepiece m body f ith two o w g rin stationary consists a and rotating a parts, bing components: plum S B A available hsrn peet h oaigeeic odrfo from holder eyepiece assembled, is rotating the to turret used the prevents n e h ring coupling W this same piece. Last the from rotating assembly. the ed m sleeve r make e trim n in ring f the o outer precisely an to curve is r Jim rio resin, te in turret, two-part the his ith atch for w m But holder and sleeve. r 45° e diagonal to a n in bent cast the bracket inside inum ounted m alum an Jim to affixed eyepiece. be the can feed to r allow to irro m rilled d is diagonal hole a the ich from h t w ligh into cylinder, single a f o air p a is piece Next rear plug. The ith w parts. adaptor bing cleanout plum 2-inch S a B is A f four o eyepieces. consisting the secure to used screws set nylon three the glued then e H press. rill d a in locations saw the hole ith w he arked m tape ference, circum asking f m o outer its piece a round affixed A fitting. coupling sliding o ff the front o f the assembly. f the o front the ff o sliding it and diagonal, star old an from r irro m the salvaged form to together glued are pieces three These spacers. 2 hole. each into couplers electrical-conduit C PV a ith eter w diam holes the cut e H holders. eyepiece five f the o Housed inside the stationary section is a diagonal m irror, irror, m diagonal a is section stationary the inside Housed ABS plumbing fittings. plumbing ABS The turret is made from several inexpensive and readily available available readily and inexpensive several madefrom is turret The -by-l^-inch reducer bushings (flush style) that serve as serve that style) (flush bushings reducer -by-l^-inch The inner, stationary sleeve is an assemblage assemblage an is sleeve stationary inner, The a utilized Jim , ring rotating the make To H is eyepiece turret uses inexpensive and com m only only m com and inexpensive uses turret eyepiece is H 1 V 4 -inch inside- inside- -inch 2 -inch -inch Once the two parts are complete and all the rough edges have been sanded SKY Now Available smooth, it’s time for final assembly. First, & TELESCOPE on Apple iPad the outer, rotating piece slips onto the inner sleeve, then the retaining ring is www.skyandtelescope.com/app glued in position against the front of the rotating piece. Jim made sure there was If you’re a current print subscriber enjoying your free digital just the right amount of friction to ensure edition of S&T on a desktop or laptop computer, you can now that the eyepiece wouldn’t rotate out of get a free iPad edition by downloading the Sky & Telescope position on its own, but not so much that app at the iTunes App Store. Digital issues switching eyepieces would change the include links to bonus audio interviews, □ Available on the telescope’s position. Lastly, Jim glued a videós, and image galleries. App Store 2-inch, T-thread nosepiece (purchased from a telescope dealer) to the front of the assembly so that the turret slips into his FOCUS ON scope’s 2-inch focuser. KOHL Observatory — Lakewood, NY In use, Jim notes that the best proce- The ASH-DOME pictured is an 18'6"-diameter, elec- dure is to set the telescope focuser to tronically operated unit. The observatory dome shel- accommodate the eyepiece that requires ters a 20-inch DFM computer-controlled telescope. The observatory is used for personal observing and the most in-travel. Next, he focuses the by many local grade school, high school, college, other eyepieces individually by sliding and amateur astronomy groups. them slightly out of their holders, then ASH MANUFACTURING COMPANY locks them into position with the set PO. Box 312, Plainfield, IL, USA 60544 screws. This ensures that all the eyepieces 815-436-9403 • FAX 815-436-1032 in the turret are parfocal. “I load the www.ashdome.com Email: [email protected] turret with eyepieces in ascending order Ash-Dome is recognized internationally by major astronomical groups, amateurs, universities, colleges, and of focal length and it becomes effortless secondary and primary schools for its performance, durability, and dependability. Manual or electrically operated units in sizes from 8 to 30 feet in diameter available. Brochures and specifications upon request.______and convenient to change magnification without losing the target,” Jim says. “Now, each clear night, I look forward to taking T h e 1 0 ” Astro-Tech out the scope and giving the turret a spin!” To learn more, e-mail Jim at jim _ truss-tube R-C [email protected]. ♦ is o n ly Contributing editor Gary Seronik is an expe- rienced telescope maker and observer. He can $ 2 9 9 5 ! be contacted at www.garyseronik.com. A carbon fiber truss, quartz mirrors, dielectric optical coatings - every Astro-Tech true Ritchey- Chrétien reflector (even the 10”) has premium features at a very non-premium price. Ritchey-Chrétien astrographs The Astro-Tech are the choice of professional as Truss-Tube R-Cs tronomers and observatories world-wide. 10” ...... $2,995 12” ...... 4,495 For an affordable Astro-Tech R-C, visit our 16” ...... 6,995 astronomics.com website, or give us a call. 20” ...... 12,995 astronom ics.com Telescopes • Binoculars • More A set of PVC electrical conduit couplers are glued to the outer, rotating ring. The couplers (800) 422-7876 Now in our 35th Year. serve as eyepiece holders. AstronomyTechnologies.com CloudyNights.com SkyandTelescope.com October 2014 71 Image Processing Eliminating Band H ere’s a technique that rem oves com m on artifacts f r o m DSLR and CCD images. THERE'S LITTLE DOUBT that digital SLR cameras have into clean, smooth data. opened the hobby of astro-imaging to the masses. Never Band and line noise, sometimes referred to as horizontal before has it been so easy (and relatively inexpensive) to take and vertical banding noise (HVBN), are common artifacts in great shots of twilight conjunctions, M ilky Way nightscapes, images of the night sky taken with DSLR and some CCD and even deep-sky vistas. But most DSLRs and even some cameras. The problem has multiple sources, some as a result CCD cameras aren’t perfect detectors. Although they take of your camera’s sensor readout, others due to its analog-to- exquisite daylight images, many produce “banding” and digital conversion and signal amplification using high ISO line noise that show up in low-light conditions. settings (gain settings on video cameras work in a similar Fortunately, banding and line artifacts are easy to cor- way). Banding can also come from electrical interference rect using modern astronomical image-processing pro- from adjacent equipment on the same power circuit. In all grams. Follow these steps to transform your noisy images cases, these issues can detract from an otherwise fine image. Although virtually all astrophotos from recent years were taken with digital cameras, the images often suffer from banding and line noise, which can compromise an otherwise excellent image. Author and software engineer Michael Unsold describes his innovative technique for correcting this prob- lem using his program ImagesPlus. He used this software to remove the broadbanding artifacts from the left image of NGC 7000, which was taken with a modified Canon EOS 40D. Unsold’s processing led to the smooth result at right. Unless otherwise noted, all images are courtesy of the author. 72 October 2014 sky & telescope & Line €> Noise Michael Unsold Band and line noise exist in most images taken with a DSLR, even daylight photos, though they aren’t often vis AJAY AJAY TALWAR (2; ible. This is because H VBN resides in the low-signal area of your images, such as the shadows. In daylight imagery, Left: The small-scale line noise seen in this close-up image of the Horse- light levels are easily sufficient to overwhelm that signal. head Nebula often appears in DSLR images taken at high ISO settings. Although the lines are easily corrected using a simple algorithm, Unfortunately for astrophotographers, light from deep-sky Right: bright objects such as stars have added additional artifacts in the image. objects is extremely faint compared to subjects illuminated by our Sun, so astro-imagers need to “stretch” the low-end signal to reveal most targets, such as the M ilky Way over a able artifacts around the stars — particularly new dark landscape or the faint ion tail of a comet. This stretching bands that emanate from any bright stars or galaxy nuclei unfortunately also amplifies band and line noise. in the photo. Line noise appears as a periodic pattern of narrow vertical or sometimes horizontal lines that become more Targeted Processing: Line Noise pronounced as you enhance an image. Banding is similar, The best approach to correcting band and line noise is to though with much wider “stripes” than what appears with split the image into two separate files in ImagesPlus as B la ir line noise. These stripes often have a color bias in color MacDonald describes in detail in the June issue (page 72); images, with some bands in blue, green, or red. abridged star-splitting directions appear below. By splitting Popular methods for correcting these artifacts attempt the image onto two images, one with only the stars and to mask or blur their effects but do not actually remove the other with the lines, bands, and other subject matter them from your data. These techniques can also soften (we’ll call this the “subject image”), we can target just the image detail, which reduces the final quality and sharp- artifacts while avoiding the introduction of additional ones. ness of your image. Using my program ImagesPlus, w hich The split is done in a lossless state so that you get the same I wrote specifically for processing astronomical images image as you started with when you merge the split star taken with color and monochrome cameras, I ’ve devised a and object images. You then create the final photo by merg- technique that removes line and band noise from an image ing the corrected image with the star image. You can cor- without loss of small-scale detail. rect band and line noise in ImagesPlus using either “raw,” unprocessed data or a final image. Simple Correction Theory To split the stars and subjects into two images, begin The key to rem oving band and lin e noise is to first recog- with your calibrated and combined image in ImagesPlus, nize that these signals are periodic and repeat at specific and select Special Functions / Mask Tools / Feature Mask frequencies. As such, they are best corrected using the Fou- © from the pull-down menu. A new window opens, where rier transform function, a mathematical tool that allows you can adjust the star radius size, threshold, and Mask you to target specific frequencies and remove them from Area Size until you’re satisfied that you’ve selected all the digital images. stars and other bright features in the image. Make sure The problem is that many desirable features in our that your selection includes the bright nuclei of galaxies, astrophotos, particularly the ever-present stars, also occupy bright planetary nebulae, or comet heads, since each can some of the same frequencies as the lines and bands. So if add artifacts to your result if not properly selected. you globally apply line or band suppression using a Fourier Once you’re satisfied with your selection, click the Split transform to an image with stars, then you’ll not only Stars button at the bottom right of the window. In a few remove the lines and bands, you’ll also introduce undesir- moments, you’ll have two images: one with only the star SkyandTelescope.com October 2014 73 Image Processing Identify and separate Feature Mask © - CombineFilesExcAvg-450Dlines_1.fit — the stars and other bright objects from the fainter signals in your image using the Thresbold Feature Mask © tool Masked A/ea Se e ------(far right). Move the Fill R adius Star Radius slider to p " Enable ---- '------the right to increase the amount of stars Remove Small Stars JfímdowSae EffectSae in your selection, and » p " Enable Least M°M [55 3 Is*® 3 expand the area of your mask by moving Special Star/A/ea Processing (~ Select „ . 1 S ...... 5 l l l £ l ByP«.i the Masked Area Size (• Remo\ Rad«» - J ------^ U..en,| slider to the right, C ludf Display Cokx All | producing the black (í >'/R C G/B C Irrviait Color Mode Output masks in the image W Enable Sliders Lock Image Spltl Stars | (8 RGB (8 NoSta at near right. C R.G.B C Stars J Don* | Ű. data, and the other with your nebulae, galaxies, and other the Horizontal W idth parameter and repeat the process subject matter in addition to the bands and lines you want until they are no longer visible in your image. to correct. ImagesPlus uses two separate tools to correct lines and Removing Bands bands, and since both artifacts don’t always appear in If your image suffers from wide colored banding, split every image, let’s begin by correcting an image with line the image into stars and subject images as described noise. Click on the subject image and open the Smooth earlier. Next, select Smooth Sharpen / Band Suppression Sharpen / Line Enhancement and Suppression Tool to from the pull-down menu. A small dialog window opens, remove the fine vertical-line pattern. A dialog window where you can select the Enable Vertical Band Suppres opens, with a few important options. If your photo suf- sion or the horizontal option. Depending on which you fers from vertical or horizontal line noise, select which choose, the top Suppress slider controls vertical banding, type you want to address in the Elim inate section. Next while the second slider adjusts for horizontal bands. Both you’ll change the Vertical Height to the maximum set- begin at the “Most” setting at right, so reduce the number ting of 121 in the Line Detection Window Size in Pixels slightly and wait a minute for the program to process your section. Now you want to adjust the Horizontal Width image. I suggest lowering the setting in increments of 5 parameter and click the “Apply” button. I suggest start to narrow down what works best for your particular photo. ing with the lowest setting first. When you’re happy with the result, click the “ Done” In a minute or so, the process completes and displays button, and you can proceed to recombine the star image your result. If lines are still visible in your image, increase with your nebulae, galaxy, or nightscape photo. % Once you’ve split the stars and other bright objects into a separate image, click on the image with your target object and open the Line Suppression & Enhancement tool. Simply select the Horizontal Lines, Vertical Lines, or both from the Eliminate section of the tool, and adjust the height and width options until the lines disappear from your photo. 74 October 2014 sky & telescope Wide banding can be addressed using the Band Suppression tool in ImagesPlus. Click on your subject image then open the tool and select the Enable Vertical Band Sup pression (or horizontal if necessary). Pull the Suppress Vertical (or Horizontal) sliders left to reduce the effect on your image until you match the width of the bands. Select the Special Functions / Combine Images Using button, and then save your final result. / Blend Mode, Opacity, and Mask. This time two wid- You can apply band and line correction to any color ows open — the Combine Images Setup window, where or monochrome image, and the correction can help with you first can title the combined result, and the Combine most astronomical images to rid them of repeating noise. Images window. The Combine Images Setup window Many high-speed video cameras used for planetary imag- allows you to title your merged result, then click OK. In a ing often suffer from line noise, too, and you can quickly moment, a new image appears, and the Combine Images address it with this technique. Tools such as these are window displays a list with the working titles of your often the final key to raising your images to the next level image and stars-only photos. Make sure your corrected of proficiency. ♦ image is at the bottom of the image stack by clicking the up or down arrows. Next, change the Blend Mode of the Michael Unsold has grown ImagesPlus to a mature astro star image from Normal to Merge Split. In a moment both nomical imaging program for DSLR and CCD imagers alike. images w ill appear as a combined result. Click the Flatten Explore its other features at www.mlunsold.com. O CombirK»FilesExcAvg-45ÖDlines_1 Split Stars fit - RG When you’ve corrected the line or band noise in your subject image (lower left), recombine the stars (upper left) with your subject using the Blend Mode, Opacity, and Masks tool (far right). Combine Images - CombinelmagesTargeM.fit Cembn* lma9tt r Adaton r • BtondiOpoay ondMotfc Bland Mód* M*fga Spin Some* Imeg* St«cV Cud*. So«xc* Imeg* V) r Addlmoe* F I- Add Maik l” "Mm. 3 Ü l l 4 ByFW Top | t i | ű u Botom | m Oiplay Combmobon Ü Make sure your star image is at the top of the stack, then change its Blend Mode to Merge Split. Click the Flatten button to produce a fine result (center). SkyandTelescope.com October 2014 75 Sean Walker Gallery ( V • ■ V • • • • :X; • * • • X • v • 0 • • • •• f . •• A 76 October 2014 sky & telescope Visit SkyandTelescope.com/gallery for more of our readers’ astrophotos. < REFLECTIONS OF MONOCEROS Gerald Rhemann This colorful region in Monoceros boasts a cornucopia of nebulosity, including long streamers of dark dust, red- dish emission, and bluish reflection nebulosity. Details: ASA12N-OK3 f/3.6 astrograph with FLI Micro- Line ML8300 CCD camera. Total exposure was 1 1 / hours through color filters. y A CELESTIAL SPARE Damian Peach Located in the southern constellation Grus, planetary nebula IC 5148, the “Spare Tyre Nebula,” displays thin arcs of material in large amateur instruments. Details: PlaneWave Instruments CDK700 corrected Dall- Kirkham telescope with FLI ProLine PL16803 CCD camera. Total exposure was 1 / hours through Astrodon color filters. y BETWEEN TARGETS Eric Africa The glowing, pinkish gas of Barnard’s Loop bisects this region of Orion between the dusty batch of LBN 1622 at top left and the reflection nebula M78 at bottom right. Details: Takahashi FSQ-106N astrograph with SBIG STL- 11000M CCD camera. Total exposure was 21 hours through Astrodon color filters. SkyandTelescope.com October 2014 77 A CRESCENT EMBRACE Terry Hancock Long filaments of hydrogen gas from the expansive nebula IC 1318 (left) curve around brighter NGC 6888, the Crescent Nebula, at the lower right. Details: Takahashi Epsilon-180ED astrograph with QHY11 CCD camera. Total exposure was 4.4 hours through color and H a filters. ► ASHEN MOONRISE Steve Thornton The waning Moon rises through smoke and ash clouds from wildfires as seen from Murrieta in southern California on the evening of May 18th. Details: Nikon D300 DSLR with 70-to- 200-mm lens. Total exposure was 4 seconds at f/5.6, ISO 400. ♦ Gallery showcases the finest astronomical images submitted to us by our readers. Send your very best shots to gallery@ SkyandTelescope.com. We pay $50 for each published photo. See SkyandTelescope.com/aboutsky/guidelines. 78 October 2014 SKY & telescope www.observa-dome.com As the country’s oldest dome manufacturer, Observa-DOME has developed an expertise unmatched in the industry. Our clients are world-wide, from the United States Government to the amateur astronomer. No matter what the use, the climate, the installation, the design, Observa-DOME meets the challenge. What Do« a Black Hole Look Like? In this sophisticated introduction, leading astronomer Charles Bailyn goes behind the theory and physics of black holes to describe how astronomers are observing these enigmatic objects and developing a detailed picture of what they look like and how they interact with their surroundings. Cloth $35.00 PRINCETON UNIVERSITY Fax (601) 982-3335 • [email protected] Jackson, MS 39213 PRESS Sell Your Used Equipment — For Free! And you'll be in good company! Loads of ad listings featuring products for sale priced from $4.95 to $595,000. It's been amazing how quickly gear has been selling too; in many cases, in just days! Easy to use, outstanding product presentation, and it's free! I INCMVIDOAl (PRIVÁTÉ PARTY) J IKMVWUAl |MN Losmandy G 11 wi Gemim 1 L4 on CI700 I npo FREE AD LISTINGS FOR INDIVIDUALS FREEALERTS As an individual selling your own personal If you are looking for something specific, K gear, you can place an ad online at Market- register to receive e-mail alerts when new Place free of charge — and it will remain ad listings appear that match your saved a in place for up to 12 months or until the search criteria. Registering to enjoy this product sells. feature is simple — and free. sa: MarketPlace SkyandTelescope.com/marketplace ECLIPSE •MARCH 2016 INDONESIA, MARCH 1-17, 2016 a , http://InsightCrui Sail roundtrip Singapore on Holland America Line’s Cruise prices vary from $1,999 for an interior Róbert Naeye stateroom to $8,299 for a Neptune Suite, per ha s been Sky & Volendam with Sky & Telescope’s Bob Naeye, person, based on double occupancy. (Plus gov't Telescope's Editor Australian Sky & Telescope editor Greg Bryant, and taxes and fees, $329; booking service fee, $100; in Chief sin ce cruiseline gratuities, $11.50 per day; and Tour 2008. Previously he astronomers Dr. David Tholen and Dr. E.C . Krupp on the Leader gratuities, $100. For those attending our was Senior Editor eclipse trip of a lifetime. Program, there is a $1,075 fee. (The Program fee at Sky & Telescope includes eclipse-viewing glasses, 13 seminars, a and Senior Science Join the fun and experience legendary Indonesia's cultures. You can planetary debate, Q&As, and several receptions.) Writer for the Astrophysics Science Division of explore Komodo, Bali, Lombok, UNESCO sites, and traditional cuisines Book by October 1st and save $300 per person NASA’s Goddard Space Flight Center. Robert is on the Program fee For full terms and condi- all in the company of fellow eclipse buffs. When it's time to capture the author of two books: Through the Eyes of tions please visit: InsightCruises.com/Sky-7 Hubble: The Birth, Life, and Violent Death of eclipse memories, tap Sky & Telescope’s expertise. Reserve now for Stars and Signals from Space: The Chandra best cabin selection as this sailing is guaranteed to sell out. X-ray Observatory. Dr. E.C. Krupp While the full eclipse cruise is 16 days if you wish you can join the is an astronomer Greg Bryant has group after the initial Singapore departure and leave the cruise early, and Director of been Editor oí A ustralian Griffith Observatory in Bali, spending as few as nine (9) days onboard. Sky & Telescope since in Los Angeles. He 2006 and a Contributing received his M.A. Editor to Sky & Telescope and Ph.D. in since 2001. He has astronomy at UCLA, also been involved with where he studied the properties of rich clusters the publication of an of galaxies as a student of Professor George O. Australian annual astronomy yearbook since the early Abell. He started his career at Griffith Observatory '90s and science writing for the Australian Research in 1970. Dr. Krupp has personally visited, studied, Council's Centre of Excellence for All-Sky Astrophysics. and photographed more than 2,000 ancient, his- A keen amateur astronomer for more than 30 years, toric, and prehistoric sites throughout the world Greg most recently teamed up with Insight Cruises for and has led or supported 13 total solar eclipse their successful 2012 Total Solar Eclipse tour in Aus expeditions and four annular eclipse efforts. tralia. In 2000, the International Astronomical Union named asteroid 9984 Gregbryant in his honor. Dávid Tholen, Ph.D. is an astronomer at the Institute for Astronomy of the University of Hawaii (IfA), who specializes in planetary and solar system astronomy. Winner ofthe American Astronomi cal Society Division for Planetary Science’s Urey Prize in 1990, Dr. Tholen and his stu d e n ts have discovered many near-Earth asteroids, the most famous being Apophis, which will make an extremely close approach to the Earth on April 13, 2029. Add eight (8) hours to UT tim e for local time. I.e., the start of the total eclipse (C2) will be 8:35am. SKY ACCESSORIES & TELESCOPE MEADE SCT UPGRADES For focus, clutch, M a r k é t drives, light thru-put, mounting, carrying & balancing. Your essential source for astronomical products EZ BINOC MOUNT KIT P l a c e m m Outdoor mount handles * all size binoculars. • • View standing, sitting ACCESSORIES ACCESSORIES y * orreclining. $106.95 u í » • > T h riE R S O N Laser Collim ators & Accessories Howie Glatter’s i i i W " IhNGINEERING tuBlug ™ and Blug™ Barlowed collimation aids www.petersonengineciring.com 401-245-4068 SkyPointers™ & brackets -Glatter Mirror Sling kits W T I ^ Z L O M O T IO N ™ Manual Tracking for DOBS Dual Axis - EZ Install 2012 X Stainless Steel & SKY 0 7 Bronze Hardware ^$ 3 4 9 5 3 a Tcuscorc . % „ .. US Patent Pending 423-867-9911 • [email protected] The Parallizer™ www.chattmill.com 2” -1.25” adapter for Pcrfect Parallel Alignment Howie Glatter 3850 Sedgwick Ave. Bronx, N.Y. 10463 Tel/Fax (718) 7963203 . www.skypointer.netiVww.collimator.com • c-mail: [email protected] = i M A « 0 l 0 IIC H tlD » U I t i «$ .S S STAR TISTING QQ ASTIONOMICAl IIKKOMS I T3-JÜ < S KJ íO | m V LJ_ COMPUTER SOFTWARE Foster Systems Serving astronomers and observatories worldwide Rol l off Roof & Dome Control lers Deep-Sky Planner 6 \^QT • A SC O M compliant interface • Automatic or Manual ops. 1 • Power monitoring and mgt. 2014 • Weather monitor integration From $247 • Dew Management With Software Visit us at www.fostersystems.com www.knightware.biz Advertisein M a rk e tf)^ Now Build your own T WUrAC N T 3 / custom adapter at eShel www.preciseparts.com Professional fi bér-fed C l / V LESTER STOCKMAN - echelle Spectroscopy ^ | \ . V PHONE: 617.758.0253 305 253-5707 P r e c i s e P a r t s & TELESCOPE [email protected] Custom P u n t rom astmomomy W W W . SHELYAK.com SkyandTelescope.com October 2014 81 MISCELLANEOUS ORGANIZATIONS OBSERVATORIES / DOMES HOME-DOME AND PRO-DOME OBSERVATORIES 3 PROFESSIONAL DESIGN — AMATEUR PRICE ★ 6', 10' and 15' Diameter CloudWatcher ★ Stand-alone or On Building Low cost, accurate ★ All Fiberglass system to detect • ★ Easy Assembly cloud cover, light levels ★ Manual/Computer Automated and first traces of rain. ★ Full Height/Handicap Access With DDW interface. ★ Priced from $3,295 www.clouddetection.com C all or write for a FREE Brochure www.darksky.org TECHNICAL INNOVATIONS Phone: (407) 601-1975 www.homedome.com TELESCOPES Equatorial Fork Mounts ^OFFICINA * . ‘ “ . . . Observatory Germán Mounts V T “ The RiDK represents the new reference point for all modified v Dall-Kirkham instruments available on the market. The unique experience and creativity of Massimo Riccardi, ■ . Chief Optical Designer at Officina Stellare, gives birth to a astrograph range of superior performance and image V qu ality. RiDKs are available in 300 mm F/8and 400, 500 and . 600 mm F/7. versions. Larger diameter on request. Corrected - field diameter up.tö 80 mm.'Detailed flyersavailable online. / í \ r7'/ / RiDK: THE ULTIMATE * • ' N‘ ' TELESCOPE* OS FlagshipDealers in USA: TELESCOPE!1 www.officinastellare.com www.bisque.com - www.nmsouthernskies.com - www.optcorp.com - www.telescopes.net W ith over 34 years of experience, we offer mounts that provide the size, stability, and precision for serious astronomical observation. mathis-instruments.com 925-838-1487 Sky & Telescope’s SkyWeek Available on the IApp Store mm SHOPm • V www.ShopatSky.com 82 October 2014 sky & telescope TELESCOPES TELESCOPES C LASS IFIEDS JMI telescopes, cases, telescope ASTROPHYSICS MAJOR $200,000 PRICE REDUCTION! dollies, focusers, mirrors, and .Dedicatedto Stunning, unique, one-of-a-kind research LOTS more!! grade 12-inch f12.2 D&G refractor of superb Craftsmanship! optical quality (plus companion telescopes) on unique, custom-made Byers Series III N ew !!! . Portability& Go-To tracking Capacity mounting. Details in February 2013 issue for Lightbridge 11QOGTO Absolute Encoder of S&T, pp 66-69. See more details (plus 1 0 "and 12" Option a video) on SkyandTelescope.com’s on with GPS. Also line MarketPlace under “refractors.” Entire Train and package now offered at $595,000. Contact Track (T-N-T) Ed Noffsinger: [email protected] available! or 831-427-1011. NEW SOLAR HOME on 20 acres, 4 miles from Portal, Arizona. Quality PV system. 16” wide masonry construction. 1,134-sq- 25" Folded ft plus foundation for guest house or Newtonian observatory. 360-degree views. Dark (no ladder skies. Privacy. $207,000. Phone: 575 required!) 557-0527. REAL ESTATE: Land and homes for sale in Southern Utah’s high desert - the Click on our RED TAG SPECIALS! second darkest place in North America. Refurbished, blemished, and used Noted for deep sky viewing. Properties telescopes available at great prices! are located between Bryce Canyon and Capitol Reef National Parks. Small remote communities surrounded by 97% Jim's Mobile, Inc. government lands. Electricity, water, JimsMobile.com www.astro-physics.com internet access and complete comfort 303-233-5353 Tel • 303-233-5359 Fax Machesney Park, IL‘ USA while living in the wilderness! Homes on the Ph: 815-282-1513 market now ranging in price from $190,000 to $470,000. Land ranging in size from 2 to 47 acres priced from $48,000 to $350,000, all with exceptional views of the landscape Join us and expect and the sky. For more information, visit www.bouldermountainrealty.com or call the extraordinary. Cathy Bagley, Broker, Torrey, Utah, 435 425-3200. 2015 FO R RENT: 3 BR/2BA fully furnished adobe home in ARIZONA SKY VILLAGE in SOUTHERN SKY Portal, AZ. Observe and photograph under - Costa Rica - the darkest, clearest and most transparent skies with astronomers from all over the TOTAL ECLIPSE world. World class birding, too! irkitzman@ - Svalbard - gmail.com www.arizona-dreaming.com. - Faroe Islands FO R S A L E : TAL 200mm Klevtsov- AURORA & CULTU Cassegrain Telescope. TAL200K 8.5 - Norway - Klevtsov/Cassegrain optical design telescope in excellent condition. 200mm aperture, includes these accessories: 2016 8X50 Finderscope with mounting bracket, TOTAL ECLIPSE 90 degree star diagonal, 2X Barlow lens, 10mm Super Plossl eyepiece, 25mm - Bali New Year - Super Plossl eyepiece, crosshair reticle Indonesia & Borneo Cruise for eyepiece. Manufacturer’s web page: www.talteleoptics.com/tal200k.html Price: $1,495 plus shipping. Write ads@ SkyandTelescope.com. TRAVELQUEST Classified ads are for the sale and purchase of noncommercial merchandise, unique items, or job TravelQuestTours.com offers. The rate is $1.50 per word; minimum charge of $24; payment must accompany order. Closing 1 800 830-1998 date is 15th of third month before publication date. SkyandTelescope.com October 2014 83 Inside This Issue & TELESCOPE Specialty astronomy equipment dealers and manufacturers are an important resource for amateur and prcfessional astronomers alike — patronize our advertising dealers in this issue and enjoy all the benefits o f their expertise. Product Locator AUTOGUIDERS FILTERS OBSERVATORIES Santa Barbara Instrument Group (Page 3) Finger Lakes Instrumentation (Page 87) Observa-Dome Laboratories (Page 79) SBIG.com FLIcamera.com Observa-dome.com 805-571-7244 585-624-3760 800-647-5364 BINOCULARS Meade (Page 5, 9, 13, 17) SOFTWARE Meade (Page 5, 9, 13, 17) Meade.com Fisch Image Lab (Page 88) Meade.com 800-919-4047 | 949-451-1450 ExploreScientific.com 800-919-4047 | 949-451-1450 888-599-7597 Tele Vue (Page 2) CAMERAS TeleVue.com Software Bisque (Page 55) Apogee Imaging Systems (Page 17) 845-469-4551 Bisque.com CCD.com 303-278-4478 916-218-7450 FOCUSERS Finger Lakes Instrumentation (Page 87) TELESCOPES Finger Lakes Instrumentation (Page 87) FLIcamera.com Explore Scientific - Bresser (Page 88) FLIcam era.com 585-624-3760 ExploreScientific.com 585-624-3760 888-599-7597 MOUNTS Meade (Page 9, 11, 15, 19) iOptron (Page 11, 29) iOptron (Page 11, 29) Meade.com iOptron.com iOptron.com 800-919-4047 | 949-451-1450 866-399-4587 866-399-4587 Santa Barbara Instrument Group (Page 3) Mathis Instruments Meade (Page 5, 9, 13, 17) SB IG .co m Meade.com V1(Page E > 82) / 805-571-7244 mathis-instruments.com 800-919-4047 | 949-451-1450 925-838-1487 EYEPIECES PlaneWave Instruments (Page 82) Explore Scientific - Bresser (Page 88) Meade (Page 5, 9, 13, 17) PlaneWave.com ExploreScientific.com Meade.com 310-787-9411 888-599-7597 800-919-4047 | 949-451-1450 Sky-Watcher USA (Page 7) Meade (Page 5, 9, 13, 17) Paramount (Page 87) SkyWatcherUSA.com Meade.com Bisque.com 310-803-5953 800-919-4047 | 949-451-1450 303-278-4478 Tele Vue (Page 2) Tele Vue (Page 2) PlaneWave Instruments (Page 82) TeleVue.com TeleVue.com PlaneWave.com 845-469-4551 845-469-4551 310-787-9411 Tele Vue (Page 2) TeleVue.com 845-469-4551 Dealer Locator CALIFORNIA CALIFORNIA OKLAHOMA Oceanside Photo & Telescope (Page 61) Woodland Hills (Page 55) Astronomics (Page 71) Optcorp.com Telescopes.net Astronomics.com 800-483-6287 818-347-2270 800-422-7876 To advertise on this page, please contact Peter Hardy at 617-758-0243, or [email protected] 84 October 2014 sky & telescope Index to Advertisers Apogee Imaging Systems. .15 Oceanside Photo & Telescope...... 61 SKY & TELESCOPE A rte m is...... 19 Officina Stellare. .82 SkyandTelescope.com 800-253-0245 Ash Manufacturing C°., Inc...... 71 peterson Engineering Corp...... 81 Astro-Physics, Inc.. .83 PlaneWave Instruments . 82 IN THE NEXT ISSUE Astronomics...... 71 PreciseParts. . 81 Bob’s Knobs...... 81 Princeton University Press...... 79 CNC Parts Supply, Inc...... 81 Santa Barbara Instrument Group...... 3 Explore Scientific - Bresser. .88 Shelyak Instruments...... 81 Finger Lakes Instrumentation, LL C ...... 87 Sky & Telescope...... 61, 71, 79-83 Sculpting Planetary Nebulae Foster Systems, LLC . .81 Astronomers still struggle to understand Sky-Watcher U SA...... 7 how stars create the delightful and bizarre shapes of planetary nebulae. Glatter Instruments...... 81 Software Bisque...... 55 Galaxy Pairs and Trios International Dark-Sky Association...... 82 What's better than a galaxy? Two or three in the same field of view. StellarVue...... 83 iO p tro n ...... 11, 29 Eclipse Technical Innovations. . 82 Preview JMI Telescopes...... 83 Fred Espenak and Ja y Anderson Tele Vue Optics, Inc...... 2 point you to the Knightware...... 81 best places to go to view the next three The Teaching Com pany...... 35 total solar eclipses. Lunatico Astronomia .81 o Astronomy Cartoons TravelQuest...... 83 Mathis Instruments .82 Celebrated science cartoonist Sidney Harris explains his sources for artistic inspiration. Meade Instruments Corp...... 5, 9, 13, 17 Willmann-Bell, Inc...... 81 On newsstands Metamorphosis Jewelry...... 82 Woodland HN|s Telescopes .55 September 30th! Find us on Observa-Dome Laboratories...... 79 ZLomotion. . 81 Facebook & T w itte r m> TRACI DABERKO view O rion under a cold w in ter sky may may sky ter in w cold a under rion O view W naked-eye observing can be very reward- very be can ember, Rem observing hobby. naked-eye our an to as fee n itiatio binoculars or in they feel telescope a ay m own ust m audiences to our them that point the overemphasize instru- often our we for ents, As m factor. negative a be also instru- use. the we about ents m learn to and sky night involves effort The to participant. spectator active an appreciative to an from required progress effort the the as soon as discovers or person orning m forgot- next are the by wows” Truth ten “ f those parties. o star most our told, at be !” we w o W when y “ the astronom hear ateur am to world the Winning Converts to the Cause the to Converts Winning order to the apparent random chaos o f the f the o chaos random bring apparent to the to study order and reading self-motivated 86 It takes effort to turn interested people into full-blow n am ateur astronomers. ateur am n full-blow into people interested turn to effort takes It e The weather we m ust contend w ith to ith w contend ust m we weather The oa Point Focal e k i l October 2014 o t e v e i l e b tel e p o c s le e t & y k s we are converting converting are we t Probst rt e B W here are the boundaries o f the universe, f the o boundaries the are y h here W W see? I can far ow H there? up t’s a h W star at f telescopes o lots see we Yes, weak. have an inherent cu riosity about the night night the about riosity cu inherent an have see?” to there is else starlight. far gathering dust ber num the gathering exceeds attics f scopes and o ber basements num oper- in the ith but w telescopes, friends any ating m know and is flesh parties the but g illin w is irit sp the parties, Station. Space m iu Irid f International o the age and our in flares is true is h T larly articu p encouraged. be should and ing does it change from season to season? season? to season from change it does as: such questions by intrigued be and sky what Jupiter, and Venus, Saturn, oon, M I have a telescope, but after looking at the the at looking after but Yeah, “ telescope, heard, a you have I have es tim any m ow H To overcome these obstacles one m ust ust m one obstacles these overcome To For m any people I encounter at star star at encounter I people any m For years. He presents astronomy classes at the at classes astronomy He presents years. ply sim are folks any m there, up are views the is such feedback; receive never ay m you it when but often, happen not may is h T e W in. come outreachers where is is h T gietefa . o oi! ♦ it! do Go to e. you flam for the aiting w ignite there out astronomers group. olitical was p some f equinox o f the o parade a you precession when the days early thought quick own a do your to Just flashback knowledge. press your im to ith not w them audience, your guide at help ber em Rem neophytes. fragile ling and h sky. night the ith w intrigued not beautiful any m how accept atter m ust no m we that fact And the issionary. m f a o plight inherent that kindle can example, you effort, patience, and dedicated ll ith W fu their potential. discover people help to need hobby. our from enjoy f satisfaction to o e potential lifetim ll a fu not their to have they but awakened f curios- ent, o wonderm attributes and ity inherent the ith w born alike? are true be really snowflakes it two Can no that thick? iles m be ciers only see we do y h W ? shoot- do from come here W stars ing boundaries? are there f i and conducts astronomy events at Acadia eventsat astronomy conducts and 40 than more astronomer for amateur an to there are you lectures, and parties star sometimes nd A gratifying. so oh is it does astronomer. ateur am ing flam a into spark as: such ysteries, m insoluble ingly seem alone? we re A oon? M f the o side one National Park in Maine. in Park National been has Probst Bert NASAengineer Retired gla- can ow H there? are stars any m ow H Ellicottville, New York Memorial Library YorkMemorial New Ellicottville, Take heart; there are born am ateur ateur am born are there heart; Take astronomers ateur am any m are There One m ust also have an attraction to attraction an have also ust m One Exam ple and patience are vita l when when l vita are patience and ple Exam Trifid Nebula imaged with MicroLine MLx694 and Tele Vue NP127. Image courtesy of Wolfgang Promper. “Perfection” — Wolfgang Promper Wolfgang Promper recently took an FLI MicroLine MLx694 to Tivoli AstroFarm in Namibia. Paired with the Tele Vue NP127, CenterLine filter wheel, and Atlas focuser, the results were spectacular! His review: “The sensitivity is amazing, the noise extremely low, but what I really felt is that it is the perfection we all are looking for. Every subframe looks like a calibrated master and it connects you directly to the object you're imaging. If it were a musical instrument, I would compare it with a Stradivarius.” At Finger Lakes Instrumentation, we design and build unrivaled cameras, filter wheels, and focusers to pave your way to success— whichever path you choose. Designed and manufactured in New York, USA. Visit us at www.flicamera.com MicroLine MLx694 camera for more information Readout Noise: 3 electrons about our cooled CCD Peak Quantum Efficiency: 75% Cooling: 60°C below ambient cameras, focusers, and Dark Current: <1 electron/hour color filter wheels. © 2014 Finger Lakes Instrumentation, Inc. All rights reserved. WELCOME TO THE NEXT GÉN ERATION OF DISCOVERY ► Sirius, the brightest star in the ' ' heavens.;.. My grandfather 4. wQÜId say .we're part űf sohrie- , thing inoredibly wonderful - ' more marvelous than wé jj£\ , jnhagine. He would say we ? ought to gooüti:p^;look át.it ' G 3 E 9 once in a while.so we don't lose our piacéin it. . ► Affordable True •• 'WHm > Róbert Limited Diffraction Performance Products ______® What willyóu;discóVer? EXPL S C I E N T I REFf iI Cn 4 explorescientificusa.com - 866.252.3811 * * Ask About Our á ■> @2014 Explore Scientific