Astronomer's Computer Companion / Jeff Foust and Ron Lafon

Total Page:16

File Type:pdf, Size:1020Kb

Astronomer's Computer Companion / Jeff Foust and Ron Lafon astronomer’s computer companion Jeff Foust &Ron LaFon San Francisco the astronomer’s computer companion. Copyright by Jeff Foust and Ron LaFon All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any informa- tion storage or retrieval system, without the prior written permission of the copyright owner and the publisher. Printed in the United States of America c Printed on recycled paper — Trademarks Trademarked names are used throughout this book. Rather than use a trademark symbol with every occurrence of a trademarked name, we are using the names only in an editorial fashion and to the benefit of the trademark owner, with no intention of infringement of the trademark. :William Pollock :Karol Jurado :Derek Yee Design :Derek Yee :Margery Cantor copyeditors:Gail Nelson, Judy Ziajka :John Carroll :Nancy Humphreys Distributed to the book trade in the United States and Canada by Publishers Group West, Fourth Street, Berkeley, California , phone: --or --, fax: --. For information on translations or book distributors outside the United States, please contact No Starch Press directly: No Starch Press China Basin Street, Suite , San Francisco, CA - phone: --; fax: --; [email protected]; www.nostarch.com The information in this book is distributed on an “As Is” basis, without warranty. While every precaution has been taken in the preparation of this work, neither the author nor No Starch Press shall have any liability to any person or entity with respect to any loss or damage caused or alleged to be caused directly or indirectly by the information contained in it. Library of Congress Cataloging-in-Publication Data Foust, Jeff. The astronomer's computer companion / Jeff Foust and Ron LaFon. p. cm. Includes index. ISBN 1-886411-22-0 (acid-free paper) 1. Astronomy—Data processing. 2. Microcomputers. I. LaFon, Ron. II. Title. QB51.3.E43F68 1997 522'.85—dc21 97-36006 Table of Contents Chapter A Guided Tour A Quick Tour Chapter The Earth from Space What Does the Weather Look Like? Sources for Satellite Images Tell Me about the Weather Satellites That Monitor the Ozone Layer Satellite Pictures of Land and Sea LANDSAT and SPOT Images Can Be Very Pricey Some Sources for Free Images Pictures of the Earth’s Oceans And Beneath the Surface Getting the Big Picture—the Earth in Space Software That Simulates Earth Views Chapter The Moon Learning about the Moon Images of the Moon Observing the Moon and Its Effects Chapter Planets and Moons Basic Resources The Inner Planets: Mercury and Venus Mars Jupiter and Saturn The Outer Planets: Uranus, Neptune, and Pluto Chapter Asteroids and Comets Asteroids and Meteors Comets Halley, Hyakutake, and Hale-Bopp Chapter The Sun The Basics of the Sun Solar Research Sunspots and Flares Aurorae Solar Eclipses Chapter Other Stars Stellar Basics Double and Variable Stars Finding Stars and Constellations Other Suns, Other Planets Chapter Supergiants and Supernovae: The Deaths of Stars Stellar Evolution The Deaths of Normal Stars The Death of Giant Stars: Supernovae Chapter Neutron Stars, Pulsars, and Black Holes Neutron Stars Pulsars Black Holes Chapter Galaxies The Milky Way Other Galaxies Observing Galaxies Chapter Nebulae and Clusters History Nebulae Clusters Observing Deep Sky Objects Chapter Quasars and Other Oddities Colliding Galaxies Active Galaxies Quasars Chapter Cosmology: Beginnings and Endings The Big Bang Evidence for the Big Bang Alternative Theories The Fate of the Universe Chapter Explorations on Your Own: Offline Planetarium Software Tours of Some Planetarium Packages Advanced Observing Programs Other Planetarium Software Packages Satellite Tracking Software Weather and Time Software Astronomical Image Processing Software Educational and Other Software Tours of Some Educational and Other Software Packages Other Educational and Astronomy Software Chapter Explorations on Your Own: Online Online Services Usenet Newsgroups Mailing Lists Discussions and Chats Finding It on the Web Chapter Remote Astronomy over the Internet Publicly Accessible Automated Telescopes Bradford Robotic Telescope University of Iowa Robotic Telescope Remote Access Astronomy Project Eyes on the Skies Solar Telescope Nassau Station Robotic Telescope Older Automated Telescopes MicroObservatory Telescopes in Education Hands-On Universe Other Telescopes Chapter Computers and Amateur Astronomy Computer-Controlled Telescopes CCD Cameras Scientific Resources for Amateurs Solar, Lunar, and Planetary Observations Asteroids and Comets Occultations Variable Stars and Supernovae Appendix A Software on the CD-ROM Installation Notes What If I Have Trouble? PC Software Atmospheric Conditions Programs Clocks Flight Simulators Galaxy Programs Utility Programs Gravity Programs Image Analysis Programs Multipurpose Programs Movie Makers Observational Programs Photography Tools Planetarium Programs Satellite Programs Screen Savers Solar System Programs Star Programs Viewers Macintosh Software Galaxy Programs Gravity Programs Multipurpose Programs Utility Programs Observational Programs Plantarium Programs Satellite Programs Solar Systems Star Programs Viewers Appendix B Images on the CD-ROM 383 Appendix C Animations on the CD-ROM 427 Asteroids Eclipses Jupiter Mars Moon Neptune Pathfinder Pluto Staurn Shoemaker-Levy Sun Uranus Venus Appendix D Sources Telescopes & Accessories Books Magazines CCDs Software Miscellaneous Astronomy Clubs, Planetariums, Science Museums, and Observatories UseNet News Groups Index Viewing the Electronic Book Acknowledgments When I first started corresponding with Bill Pollock of No Starch Press in late about a book project that would become The Astronomer’s Computer Companion, I don’t think I truly understood what I was getting myself into. I know I underestimated the amount of time and effort that goes into writing a book, especially when try- ing to juggle a multitude of other projects. To make up for that, though, I also underestimated the thrill one gets when one completes a book, or even a single chapter. It’s been a fun adventure. A number of individuals and companies have graciously provided shareware or demo versions of their software that are included on the CD-ROM. I thank Eric Bergman Terrell, David Chandler, Exploration Software, David Irizarry, Larry Kalinowksi, Microprojects, David Nagy, Parallax Multimedia, Procyon Systems, Rainman Software, Stephen Schimpf, Sienna Software, SkyMap Software, and Southern Stars Software, for their fine cooperation. Bill Pollock and Karol Jurado at No Starch Press provided expert advice, guidance, and encouragement throughout the writing and editing of this book. It is through their tireless efforts that my words and ideas became the polished final product you’re reading. Most importantly, I want to thank my mother, who always encouraged my interest in both astronomy and computers, even if she never always understood what I was up to. Thanks for keeping my focus on the stars. Jeff Foust 1 A GUIDED TOUR ’ is measured in light- years, and no one knows its size for certain. The best estimates for the distance in light-years to the most Tdistant objects known range from a few to more than 10billion light-years. That’s a pretty big number. In fact, it seems almost as big as the universe of software and online resources available on astronomy. Well, there aren’t quite that many different programs and Web sites available for you to choose from, but if you’re just getting started the wide range of choices can seem a little overwhelming. What software should you use? Where should you look online for more information on an astronomy topic? It’s easy to get lost and confused in cyberspace if you don’t know what you’re looking for or how to find and use it. The situation is similar to visiting a foreign country for the first time. The sheer number of attractions—historic sites to see, muse- ums to visit, restaurants to try, shows to attend, and so on—can overwhelm the new visitor. Sometimes you take a tour or hire a guide so that your first trip into a new territory will be interesting, delightful, and different, rather than simply incomprehensible. With so many computer resources available for astronomical pursuits, it can be difficult to know where to go and what to do first if you’re interested in a particular topic. This chapter will guide you through a hypothetical situation and introduce you to some of the computer resources available to answer your questions and guide you to more information if you’re a little unsure about how to get started using your computer in astronomy, follow along on our guided tour. A Quick Tour t’s a clear weeknight in late May, just after the Memorial Day Iholiday in the near future. After a long day at work and running errands, you don’t get home until after nine in the evening. Just before you step inside, you look up into the southern sky and an unusual sight grabs your attention. You see the Moon and two bright stars below it. One of them has a definite reddish tint and is hardly twinkling. The juxtaposition of the three objects makes you curious. You know the brightest and largest is the Moon, but what about those other two stars? Why haven’t you noticed them before? Your home computer can help you answer those questions. Since you’re wondering about the names and locations of objects in the night sky, the first place to turn to is a planetarium program you’ve already purchased and installed on your computer. You start up the program and start searching. Depending on what software you’re using, you may have to input the time and your present loca- tion. For example, in some programs, like Starry Night Deluxe for the Macintosh and Windows (see Figure 1.1), you choose from a list of cities. You can save a default choice, however, so you won’t have to do this each time you start the program. Once you have the present location and time set, you turn to the southern horizon.
Recommended publications
  • Guide Du Ciel Profond
    Guide du ciel profond Olivier PETIT 8 mai 2004 2 Introduction hjjdfhgf ghjfghfd fg hdfjgdf gfdhfdk dfkgfd fghfkg fdkg fhdkg fkg kfghfhk Table des mati`eres I Objets par constellation 21 1 Androm`ede (And) Andromeda 23 1.1 Messier 31 (La grande Galaxie d'Androm`ede) . 25 1.2 Messier 32 . 27 1.3 Messier 110 . 29 1.4 NGC 404 . 31 1.5 NGC 752 . 33 1.6 NGC 891 . 35 1.7 NGC 7640 . 37 1.8 NGC 7662 (La boule de neige bleue) . 39 2 La Machine pneumatique (Ant) Antlia 41 2.1 NGC 2997 . 43 3 le Verseau (Aqr) Aquarius 45 3.1 Messier 2 . 47 3.2 Messier 72 . 49 3.3 Messier 73 . 51 3.4 NGC 7009 (La n¶ebuleuse Saturne) . 53 3.5 NGC 7293 (La n¶ebuleuse de l'h¶elice) . 56 3.6 NGC 7492 . 58 3.7 NGC 7606 . 60 3.8 Cederblad 211 (N¶ebuleuse de R Aquarii) . 62 4 l'Aigle (Aql) Aquila 63 4.1 NGC 6709 . 65 4.2 NGC 6741 . 67 4.3 NGC 6751 (La n¶ebuleuse de l’œil flou) . 69 4.4 NGC 6760 . 71 4.5 NGC 6781 (Le nid de l'Aigle ) . 73 TABLE DES MATIERES` 5 4.6 NGC 6790 . 75 4.7 NGC 6804 . 77 4.8 Barnard 142-143 (La tani`ere noire) . 79 5 le B¶elier (Ari) Aries 81 5.1 NGC 772 . 83 6 le Cocher (Aur) Auriga 85 6.1 Messier 36 . 87 6.2 Messier 37 . 89 6.3 Messier 38 .
    [Show full text]
  • 1987Apj. . .318. .1613 the Astrophysical Journal, 318:161-174
    .1613 The Astrophysical Journal, 318:161-174,1987 July 1 © 1987. The American Astronomical Society. All rights reserved. Printed in U.S.A. .318. 1987ApJ. A STUDY OF A FLUX-LIMITED SAMPLE OF IRAS GALAXIES1 Beverly J. Smith and S. G. Kleinmann University of Massachusetts J. P. Huchra Harvard-Smithsonian Center for Astrophysics AND F. J. Low Steward Observatory, University of Arizona Received 1986 September 3 ; accepted 1986 December 11 ABSTRACT We present results from a study of all 72 galaxies detected by IRAS in band 3 at flux levels >2 Jy and lying the region 8h < a < 17h, 23?5 < <5 < 32?5. Redshifts and accurate four-color IRAS photometry were 8 2 obtained for the entire sample. The 60 jtm luminosities of these galaxies lie in the range 4 x 10 (JF/o/100) L0 2 2 to 5 x lO^iTo/lOO) L0. The 60 jtm luminosity function at the high-luminosity end is proportional to L~ ; 10 below L = 10 L0 the luminosity function flattens. This is in agreement with previous results. We find a distinction between the morphology and infrared colors of the most luminous and the least luminous galaxies, leading to the suggestion that the observed luminosity function is produced by two different classes of objects. Comparisons between the selected IRAS galaxies and an optically complete sample taken from the CfA redshift survey show that they are more narrowly distributed in blue luminosity than those optically selected, in the sense that the IRAS sample includes few galaxies of low absolute blue luminosity. We also find that the space distribution of the two samples differ: the density enhancement of IRAS galaxies is only that of the optically selected galaxies in the core of the Coma Cluster, raising the question whether source counts of IRAS galaxies can be used to deduce the mass distribution in the universe.
    [Show full text]
  • Ooooooooo ° °
    LPI Contribution No. 789 57 highest basal elevation, Maat Mons, should have a well-developed, large, and relatively deeper NBZ and that the volcano at the lowest 6055 .It .... _ .... _ .... t .... t .... I .... altitude, an unnamed volcano located southwest of Beta Regio at 10 °, 273 °, should have either a poorly developed magma chamber 6054 _ o _ o or none at all [2]. Preliminary mapping of Mast Mons [3] identified o at least six flow units that exhibit greater variations in morphology ._ o o o and radar properties than the flow• of Saps• Mons. These units are 6053 o 8 o also spatially and temporally distinct and suggest the eruption of a continuously evolving magma. Although smaller in diameter, the o oo o summit c.alders is much bener defined than the depression at Saps•. The inferred young age of Mast (lOose et at. [4] suggest that it may ooooooooo° ° ° I even be "active") may mean that the chamber has not yet grown to 605tj#o_o o 6050_ .... t", ', _ .... _ ", • i • i ' "full size." explaining the relatively smaller caldera. There is no 0 1 2 3 4 5 6 evidence of radial fractures at Maat Mons, suggesting that if lateral Height (kin) dike propagation occurxed, it was sufficiently deep that there was no surface expression. In contrast, the unnamed volcano has no summit features, no radial dikes, and only three flow units that exhibit Fig. 3. Graph showing the heights of ! l0 large volcanos as • function of considerable morphologic variations within units [3]. These obser- basal altitude.
    [Show full text]
  • Abundances in the Planetary Nebula NGC 6210 Pottasch, S
    University of Groningen Abundances in the planetary nebula NGC 6210 Pottasch, S. R.; Bernard-Salas, J.; Roellig, T. L. Published in: Astronomy & astrophysics DOI: 10.1051/0004-6361/200911654 IMPORTANT NOTE: You are advised to consult the publisher's version (publisher's PDF) if you wish to cite from it. Please check the document version below. Document Version Publisher's PDF, also known as Version of record Publication date: 2009 Link to publication in University of Groningen/UMCG research database Citation for published version (APA): Pottasch, S. R., Bernard-Salas, J., & Roellig, T. L. (2009). Abundances in the planetary nebula NGC 6210. Astronomy & astrophysics, 499(1), 249-256. https://doi.org/10.1051/0004-6361/200911654 Copyright Other than for strictly personal use, it is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license (like Creative Commons). Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. Download date: 25-09-2021 A&A 499, 249–256 (2009) Astronomy DOI: 10.1051/0004-6361/200911654 & c ESO 2009 Astrophysics Abundances in the planetary nebula NGC 6210 S. R. Pottasch1, J. Bernard-Salas2, and T.
    [Show full text]
  • SAA 100 Club
    S.A.A. 100 Observing Club Raleigh Astronomy Club Version 1.2 07-AUG-2005 Introduction Welcome to the S.A.A. 100 Observing Club! This list started on the USENET newsgroup sci.astro.amateur when someone asked about everyone’s favorite, non-Messier objects for medium sized telescopes (8-12”). The members of the group nominated objects and voted for their favorites. The top 100 objects, by number of votes, were collected and ranked into a list that was published. This list is a good next step for someone who has observed all the objects on the Messier list. Since it includes objects in both the Northern and Southern Hemispheres (DEC +72 to -72), the award has two different levels to accommodate those observers who aren't able to travel. The first level, the Silver SAA 100 award requires 88 objects (all visible from North Carolina). The Gold SAA 100 Award requires all 100 objects to be observed. One further note, many of these objects are on other observing lists, especially Patrick Moore's Caldwell list. For convenience, there is a table mapping various SAA100 objects with their Caldwell counterparts. This will facilitate observers who are working or have worked on these lists of objects. We hope you enjoy looking at all the great objects recommended by other avid astronomers! Rules In order to earn the Silver certificate for the program, the applicant must meet the following qualifications: 1. Be a member in good standing of the Raleigh Astronomy Club. 2. Observe 80 Silver observations. 3. Record the time and date of each observation.
    [Show full text]
  • 7.5 X 11.5.Threelines.P65
    Cambridge University Press 978-0-521-19267-5 - Observing and Cataloguing Nebulae and Star Clusters: From Herschel to Dreyer’s New General Catalogue Wolfgang Steinicke Index More information Name index The dates of birth and death, if available, for all 545 people (astronomers, telescope makers etc.) listed here are given. The data are mainly taken from the standard work Biographischer Index der Astronomie (Dick, Brüggenthies 2005). Some information has been added by the author (this especially concerns living twentieth-century astronomers). Members of the families of Dreyer, Lord Rosse and other astronomers (as mentioned in the text) are not listed. For obituaries see the references; compare also the compilations presented by Newcomb–Engelmann (Kempf 1911), Mädler (1873), Bode (1813) and Rudolf Wolf (1890). Markings: bold = portrait; underline = short biography. Abbe, Cleveland (1838–1916), 222–23, As-Sufi, Abd-al-Rahman (903–986), 164, 183, 229, 256, 271, 295, 338–42, 466 15–16, 167, 441–42, 446, 449–50, 455, 344, 346, 348, 360, 364, 367, 369, 393, Abell, George Ogden (1927–1983), 47, 475, 516 395, 395, 396–404, 406, 410, 415, 248 Austin, Edward P. (1843–1906), 6, 82, 423–24, 436, 441, 446, 448, 450, 455, Abbott, Francis Preserved (1799–1883), 335, 337, 446, 450 458–59, 461–63, 470, 477, 481, 483, 517–19 Auwers, Georg Friedrich Julius Arthur v. 505–11, 513–14, 517, 520, 526, 533, Abney, William (1843–1920), 360 (1838–1915), 7, 10, 12, 14–15, 26–27, 540–42, 548–61 Adams, John Couch (1819–1892), 122, 47, 50–51, 61, 65, 68–69, 88, 92–93,
    [Show full text]
  • Hercules a Monthly Sky Guide for the Beginning to Intermediate Amateur Astronomer Tom Trusock - 7/09
    Small Wonders: Hercules A monthly sky guide for the beginning to intermediate amateur astronomer Tom Trusock - 7/09 Dragging forth the summer Milky Way, legendary strongman Hercules is yet another boundary constellation for the summer season. His toes are dipped in the stream of our galaxy, his head is firm in the depths of space. Hercules is populated by a dizzying array of targets, many extra-galactic in nature. Galaxy clusters abound and there are three Hickson objects for the aficionado. There are a smattering of nice galaxies, some planetary nebulae and of course a few very nice globular clusters. 2/19 Small Wonders: Hercules Widefield Finder Chart - Looking high and south, early July. Tom Trusock June-2009 3/19 Small Wonders: Hercules For those inclined to the straightforward list approach, here's ours for the evening: Globular Clusters M13 M92 NGC 6229 Planetary Nebulae IC 4593 NGC 6210 Vy 1-2 Galaxies NGC 6207 NGC 6482 NGC 6181 Galaxy Groups / Clusters AGC 2151 (Hercules Cluster) Tom Trusock June-2009 4/19 Small Wonders: Hercules Northern Hercules Finder Chart Tom Trusock June-2009 5/19 Small Wonders: Hercules M13 and NGC 6207 contributed by Emanuele Colognato Let's start off with the masterpiece and work our way out from there. Ask any longtime amateur the first thing they think of when one mentions the constellation Hercules, and I'd lay dollars to donuts, you'll be answered with the globular cluster Messier 13. M13 is one of the easiest objects in the constellation to locate. M13 lying about 1/3 of the way from eta to zeta, the two stars that define the westernmost side of the keystone.
    [Show full text]
  • Astronomy Magazine 2011 Index Subject Index
    Astronomy Magazine 2011 Index Subject Index A AAVSO (American Association of Variable Star Observers), 6:18, 44–47, 7:58, 10:11 Abell 35 (Sharpless 2-313) (planetary nebula), 10:70 Abell 85 (supernova remnant), 8:70 Abell 1656 (Coma galaxy cluster), 11:56 Abell 1689 (galaxy cluster), 3:23 Abell 2218 (galaxy cluster), 11:68 Abell 2744 (Pandora's Cluster) (galaxy cluster), 10:20 Abell catalog planetary nebulae, 6:50–53 Acheron Fossae (feature on Mars), 11:36 Adirondack Astronomy Retreat, 5:16 Adobe Photoshop software, 6:64 AKATSUKI orbiter, 4:19 AL (Astronomical League), 7:17, 8:50–51 albedo, 8:12 Alexhelios (moon of 216 Kleopatra), 6:18 Altair (star), 9:15 amateur astronomy change in construction of portable telescopes, 1:70–73 discovery of asteroids, 12:56–60 ten tips for, 1:68–69 American Association of Variable Star Observers (AAVSO), 6:18, 44–47, 7:58, 10:11 American Astronomical Society decadal survey recommendations, 7:16 Lancelot M. Berkeley-New York Community Trust Prize for Meritorious Work in Astronomy, 3:19 Andromeda Galaxy (M31) image of, 11:26 stellar disks, 6:19 Antarctica, astronomical research in, 10:44–48 Antennae galaxies (NGC 4038 and NGC 4039), 11:32, 56 antimatter, 8:24–29 Antu Telescope, 11:37 APM 08279+5255 (quasar), 11:18 arcminutes, 10:51 arcseconds, 10:51 Arp 147 (galaxy pair), 6:19 Arp 188 (Tadpole Galaxy), 11:30 Arp 273 (galaxy pair), 11:65 Arp 299 (NGC 3690) (galaxy pair), 10:55–57 ARTEMIS spacecraft, 11:17 asteroid belt, origin of, 8:55 asteroids See also names of specific asteroids amateur discovery of, 12:62–63
    [Show full text]
  • 1949 Celebrating 65 Years of Bringing Astronomy to North Texas 2014
    1949 Celebrating 65 Years of Bringing Astronomy to North Texas 2014 Contact information: Inside this issue: Info Officer (General Info)– [email protected]@fortworthastro.com Website Administrator – [email protected] Postal Address: Page Fort Worth Astronomical Society July Club Calendar 3 3812 Fenton Avenue Fort Worth, TX 76133 Celestial Events 4 Web Site: http://www.fortworthastro.org Facebook: http://tinyurl.com/3eutb22 Sky Chart 5 Twitter: http://twitter.com/ftwastro Yahoo! eGroup (members only): http://tinyurl.com/7qu5vkn Moon Phase Calendar 6 Officers (2014-2015): Mecury/Venus Data Sheet 7 President – Bruce Cowles, [email protected] Vice President – Russ Boatwright, [email protected] Young Astronomer News 8 Sec/Tres – Michelle Theisen, [email protected] Board Members: Cloudy Night Library 9 2014-2016 The Astrolabe 10 Mike Langohr Tree Oppermann AL Obs Club of the Month 14 2013-2015 Bill Nichols Constellation of the Month 15 Jim Craft Constellation Mythology 19 Cover Photo This is an HaLRGB image of M8 & Prior Club Meeting Minutes 23 M20, composed entirely from a T3i General Club Information 24 stack of one shot color. Collected the data over a period of two nights. That’s A Fact 24 Taken by FWAS member Jerry Keith November’s Full Moon 24 Observing Site Reminders: Be careful with fire, mind all local burn bans! FWAS Foto Files 25 Dark Site Usage Requirements (ALL MEMBERS): Maintain Dark-Sky Etiquettehttp://tinyurl.com/75hjajy ( ) Turn out your headlights at the gate! Sign
    [Show full text]
  • Beckett Rosenfeld Hercules O
    272 Feature Star Field STARS 273 HERCULES BY CHRIS BECKETT & RANDALL ROSENFELD Right there in its orbit wheels a Phantom form, like to a man that strives at a task. That sign no man knows how to read clearly, nor on what task he is bent, but men simply call him On His Knees [Engonasin]. Now that Phantom, that toils on his knees, seems to sit on bended knee, and from both his shoulders his hands are upraised and stretch, one this way, one that, a fathom’s length. Over the middle of the head of the crooked Dragon, he has the tip of his right foot; Aratus (fl. ca. 390–240 BC), Phaenomena, Mair trs. 1921, 384–387. The keystone star pattern of Hercules keeps the celestial sphere of summer suspended overhead for northern observers and just fits in a º9 binocular. The Romans associated the “Kneeling One” to the mythical strongman Hercules, now known as home to one of the first deep-sky objects observers learn to locate by heart, Messier 13. However, there is much more worth taking a gaze at as the constellation passes through zenith. Rasalgethi represents the “head of the kneeler” and means northern observers imagine Hercules upside down. William Herschel discovered the variability of Rasalgethi changes from an eye-catching 2.7 magnitude to a 4.0 over a six-year period, greatly altering the region of the sky. Small telescopes split it into two components, a brilliant red-orange pri- mary and rare blue-green secondary. For those more interested in star patterns than variables, DoDz 7’s sailboat-shaped pattern of stars is a low-power telescope field to the north.
    [Show full text]
  • VENUS Corona M N R S a Ak O Ons D M L YN a G Okosha IB E .RITA N Axw E a I O
    N N 80° 80° 80° 80° L Dennitsa D. S Yu O Bachue N Szé K my U Corona EG V-1 lan L n- H V-1 Anahit UR IA ya D E U I OCHK LANIT o N dy ME Corona A P rsa O r TI Pomona VA D S R T or EG Corona E s enpet IO Feronia TH L a R s A u DE on U .TÜN M Corona .IV Fr S Earhart k L allo K e R a s 60° V-6 M A y R 60° 60° E e Th 60° N es ja V G Corona u Mon O E Otau nt R Allat -3 IO l m k i p .MARGIT M o E Dors -3 Vacuna Melia o e t a M .WANDA M T a V a D o V-6 OS Corona na I S H TA R VENUS Corona M n r s a Ak o ons D M L YN A g okosha IB E .RITA n axw e A I o U RE t M l RA R T Fakahotu r Mons e l D GI SSE I s V S L D a O s E A M T E K A N Corona o SHM CLEOPATRA TUN U WENUS N I V R P o i N L I FO A A ght r P n A MOIRA e LA L in s C g M N N t K a a TESSERA s U . P or le P Hemera Dorsa IT t M 11 km e am A VÉNUSZ w VENERA w VENUE on Iris DorsaBARSOVA E I a E a A s RM A a a OLO A R KOIDULA n V-7 s ri V VA SSE e -4 d E t V-2 Hiei Chu R Demeter Beiwe n Skadi Mons e D V-5 S T R o a o r LI s I o R M r Patera A I u u s s V Corona p Dan o a s Corona F e A o A s e N A i P T s t G yr A A i U alk 1 : 45 000 000 K L r V E A L D DEKEN t Baba-Jaga D T N T A a PIONEER or E Aspasia A o M e s S a (1 MM= 45 KM) S r U R a ER s o CLOTHO a A N u s Corona a n 40° p Neago VENUS s s 40° s 40° o TESSERA r 40° e I F et s o COCHRAN ZVEREVA Fluctus NORTH 0 500 1000 1500 2000 2500 KM A Izumi T Sekhm n I D .
    [Show full text]
  • Making a Sky Atlas
    Appendix A Making a Sky Atlas Although a number of very advanced sky atlases are now available in print, none is likely to be ideal for any given task. Published atlases will probably have too few or too many guide stars, too few or too many deep-sky objects plotted in them, wrong- size charts, etc. I found that with MegaStar I could design and make, specifically for my survey, a “just right” personalized atlas. My atlas consists of 108 charts, each about twenty square degrees in size, with guide stars down to magnitude 8.9. I used only the northernmost 78 charts, since I observed the sky only down to –35°. On the charts I plotted only the objects I wanted to observe. In addition I made enlargements of small, overcrowded areas (“quad charts”) as well as separate large-scale charts for the Virgo Galaxy Cluster, the latter with guide stars down to magnitude 11.4. I put the charts in plastic sheet protectors in a three-ring binder, taking them out and plac- ing them on my telescope mount’s clipboard as needed. To find an object I would use the 35 mm finder (except in the Virgo Cluster, where I used the 60 mm as the finder) to point the ensemble of telescopes at the indicated spot among the guide stars. If the object was not seen in the 35 mm, as it usually was not, I would then look in the larger telescopes. If the object was not immediately visible even in the primary telescope – a not uncommon occur- rence due to inexact initial pointing – I would then scan around for it.
    [Show full text]