DOCSLIB.ORG

The Reflector Newsletter of the Peterborough Astronomical Association Surprising Young Stars in the Oldest Places in the Universe Dr

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Reflector Newsletter of the Peterborough Astronomical Association Surprising Young Stars in the Oldest Places in the Universe Dr Volume 13 • Issue 2 February 2014 ISSN 1712-4425 peterboroughastronomy.com twitter.com/PtbAstronomical The Reflector Newsletter of the Peterborough Astronomical Association Surprising Young Stars in the Oldest Places in the Universe DR. ETHAN SIEGEL ittered among the stars in our night sky are the famed Ldeep-sky objects. These range from extended spiral and elliptical galaxies millions or even billions of light years away to the star clusters, nebulae, and stel- lar remnants strewn throughout our own galaxy. But there’s an intermediate class of objects, too: the globular star clusters, self- contained clusters of stars found in spherically-distributed halos around each galaxy. Back before there were any stars or galaxies in the universe, it was an expanding, cooling sea of matter and radiation contain- ing regions where the matter was slightly more dense in some places than others. While gravity worked to pull more and more matter into these places, the pressure from radiation pushed back, preventing the gravitational collapse of gas clouds below a certain mass. In Globular Cluster NGC 6397. Credit: ESA & Francesco Ferraro (Bologna Astronomical Observa- the young universe, this meant no tory) / NASA, Hubble Space Telescope, WFPC2. clouds smaller than around a few have around 100,000 stars inside Sun is only 4.5 billion years old and hundred thousand times the mass them, making them nearly 100 has seen many generations of stars of our Sun could collapse. This times denser than our neighbor- live-and-die, while globular clus- coincides with a globular cluster’s hood of the Milky Way! The vast ters (and the stars inside of them) typical mass, and their stars are majority of globular clusters have are often over 13 billion years old, some of the oldest in the universe! extremely few heavy elements or more than 90% the age of the These compact, spherical collec- (heavier than helium), as little as universe! When you look inside tions of stars are all less than 100 1% of what we find in our Sun. one of these cosmic collections, light-years in radius, but typically There’s a good reason for this: our see “Globular” on page 16 2 • peterboroughastronomy.com President’s Message Report From the Executive Meeting our executive met in January to allow for travel time for the guest speaker/ formulate plans for the coming year presenter, and for some younger mem- with an emphasis on our monthly bers who may have to be home at a fixed Ymeetings. We decided to change the start time. The coffee break will follow the guest time of the meetings to 7:00 p.m. and to speaker then the “sky this month” feature continue with the format change tried out followed by any other business. I hope this at the January meeting. This means that works out well for everyone. Other items after some announcements and general in- at the executive meeting will be discussed terest items the guest speaker will have the briefly at the February meeting. floor no later than 7:30 p.m. This should ex- Rodger Forsyth pedite matters concerning astronomy, and PAA President Letter from the Editor Baby, It’s Cold Outside! anuary and cloudy nights are synony- tributed a book review of Norman Mailer’s mous, but even when the sky is clear book, Moonfire: The Epic Journey of Apollo 11. J it is bone-chillingly clear. So, happy If you haven’t already heard the news, stargazing turns into happy to staying in- club meetings will now commence at 7 p.m. side and gazing at the Hollywood Stars via with the guest speaker starting no later Netflix. than 7:30 p.m. So, until next month, wish There are some brave ones amongst our for clear skies and warmer temperatures. membership. Rick Stankiewicz braved the Phillip Chee frigid pre-dawn air to observe Comet Love- Editor, The Reflector joy. The proof is in the photo and article this month. Rick also loves the Sun and so he has given us a warm photograph of sunspot AR1944. The Reflector John Crossen enumerates the February sky for those willing to observe them this The Reflector is a publication of the Peterborough Astronomi- month He also pens an interesting article cal Association (P.A.A.) Founded in 1970, the P.A.A. is your local on star sizes. group for astronomy in Peterborough and the Kawarthas. www.peterboroughastronomy.com • [email protected] Our man Ken Sunderland returns with Phone: 705.292.0729 Club Mailing Address the final installment of his lunar series. He Rodger Forsyth, President must be moon-faced by now as he also con- Peterborough Astronomical Association 536 Robinson Road RR #1 Peterborough, ON K9J 6X2 Vol 13 • Issue no. 2 • February 2014 • 3 The Reflector Jupiter Reigns, Mars Rises and Venus Hits the Morning Sky Big Dipper in Winter. The Big Dipper stands on its handle during the winter months. As spring arrives it begins to swing overhead. This image shows it in February. JOHN CROSSEN lanet watchers have a full point of view it will be a real stunner. The night of observing in February. constellation Libra will be home to Saturn Bright Jupiter will still be close to during the late winter and spring seasons. PEarth and should be visible from sunset Venus switches from the “evening star” to until dawn. It is accompanying the constel- the “morning star” this month as it passes lation Gemini, the Twins, as they cross the behind the Sun and emerges from the other night sky. side of old Sol to become the brightest bea- Mars is brightening and takes to the con in the morning sky. sky at midnight. By the predawn hours it Uranus and Neptune are bidding us fare- is at its highest in the Southern Sky. The well as they dip behind the western horizon. Red Planet will escort constellation Virgo Mercury also joins this “sayonara set” low in through the winter night sky. Look for it the west at sunset. Canadians will have to near the star Spica. wait until late May to catch the little horizon Saturn is just a few hours behind Mars hugger as a night time target again. when February opens. It rises about 3:00 The spring constellations are chasing the a.m. in early February and at 1:00 a.m. to- winter characters towards the west. Mighty wards the end of the month. Saturn’s rings Orion is now in the south/southwest at sun- will still be tilted nicely. So from Earth’s See “February” on page 15 4 • peterboroughastronomy.com My Star is Bigger Than Your Star SUN COMPARED TO VY CANIS MAJORIS. Our Sun looks like a pea next to a tractor tire when compared to VY Canis Majoris. Shining at magnitude 7 from a distance of 4,900 light years it is well below the visual limit of the unaided eye. VYT Cma will end its life as a hypernova and end up as either a neutron star or a black hole. JOHN CROSSEN ith an estimated 200 about 2,000 feet across in comparison. billion stars in our Milky Where 1 million Earths would fit inside Way Galaxy, it should come our Sun, 7 quadrillion Earths would fit Was no surprise that some are bigger than inside VY Cma. An airplane traveling at others. Size-wise they range from tiny 900 km/h would take 1,100 years to fly neutron and white dwarfs to supergi- around it. ants and hypergiants. Numbers two and three on the list of Our Sun is way below average when it pudgy gas balls are VV Cephei and Mu comes to star size. It is ranked as a yel- Cephei. Both are in the constellation low dwarf, a designation that’s hard to Cepheus. He’s the guy married to Cas- swallow when you consider the fact that siopeia. Together they are the parents of the Sun is 1 million times larger than Andromeda in Greek legend. planet Earth. With a visual magnitude of 4.83 it is Top dog in the size race is the hyper- just at the edge of unaided human vi- giant star VY Canis Majoris or VY Cma sion. If you replaced our Sun with VV in the constellation Canis Majoris, the Cephei, it would extend out to the orbit Big Dog. If our Sun were the size of a of Saturn. 10-inch basket ball, VY Cma would be See “Big Star” on page 14 Vol 13 • Issue no. 2 • February 2014 • 5 The Reflector Comet Lovejoy in the Morning RICK STANKIEWICZ atch a comet before it’s gone, power should show you a distinct fuzzy if you can find a clear morning to ball in the star field in your eyepieces. C do so and your eyelids or fingers I tried on the morning of January 7th don’t freeze first. when it was about -22 °C with a high Comet Lovejoy (C/2013 R1) has left wind chill (-33 °C), but at least there were Hercules and is heading south through no clouds. It was close to 6 a.m. by the Ophiuchus in the eastern morning sky time I was set-up and ready to go, but and is about 30 degrees above the hori- I got a few images before my fingers zon (the angular distance of three fists started to freeze. I think anytime about end to end at arm’s length; if you don’t 1 ½ hours before sunrise is good to start have 3 fists, then improvise).
Load more

Recommended publications
  • Standing on the Shoulders of Giants: New Mass and Distance Estimates
    Draft version October 15, 2020 Typeset using LATEX twocolumn style in AASTeX63 Standing on the shoulders of giants: New mass and distance estimates for Betelgeuse through combined evolutionary, asteroseismic, and hydrodynamical simulations with MESA Meridith Joyce,1, 2 Shing-Chi Leung,3 Laszl´ o´ Molnar,´ 4, 5, 6 Michael Ireland,1 Chiaki Kobayashi,7, 8, 2 and Ken'ichi Nomoto8 1Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611, Australia 2ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), Australia 3TAPIR, Walter Burke Institute for Theoretical Physics, Mailcode 350-17, Caltech, Pasadena, CA 91125, USA 4Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Konkoly-Thege ´ut15-17, H-1121 Budapest, Hungary 5MTA CSFK Lendulet¨ Near-Field Cosmology Research Group, Konkoly-Thege ´ut15-17, H-1121 Budapest, Hungary 6ELTE E¨otv¨os Lor´and University, Institute of Physics, Budapest, 1117, P´azm´any P´eter s´et´any 1/A 7Centre for Astrophysics Research, Department of Physics, Astronomy and Mathematics, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK 8Kavli Institute for the Physics and Mathematics of the Universe (WPI),The University of Tokyo Institutes for Advanced Study, The University of Tokyo, Kashiwa, Chiba 277-8583, Japan (Dated: Accepted XXX. Received YYY; in original form ZZZ) ABSTRACT We conduct a rigorous examination of the nearby red supergiant Betelgeuse by drawing on the synthesis of new observational data and three different modeling techniques. Our observational results include the release of new, processed photometric measurements collected with the space-based SMEI instrument prior to Betelgeuse's recent, unprecedented dimming event.
    [Show full text]
  • KELT-14B and KELT-15B: an Independent Discovery of WASP-122B and a New Hot Jupiter
    Swarthmore College Works Physics & Astronomy Faculty Works Physics & Astronomy 5-11-2016 KELT-14b And KELT-15b: An Independent Discovery Of WASP-122b And A New Hot Jupiter J. E. Rodriguez K. D. Colón K. G. Stassun D. Wright P. A. Cargile See next page for additional authors Follow this and additional works at: https://works.swarthmore.edu/fac-physics Part of the Astrophysics and Astronomy Commons Let us know how access to these works benefits ouy Recommended Citation J. E. Rodriguez, K. D. Colón, K. G. Stassun, D. Wright, P. A. Cargile, D. Bayliss, J. Pepper, K. A. Collins, R. B. Kuhn, M. B. Lund, R. J. Siverd, G. Zhou, B. S. Gaudi, C. G. Tinney, K. Penev, T. G. Tan, C. Stockdale, I. A. Curtis, D. James, S. Udry, D. Segransan, A. Bieryla, D. W. Latham, T. G. Beatty, J. D. Eastman, G. Myers, J. Bartz, J. Bento, Eric L.N. Jensen, T. E. Oberst, and D. J. Stevens. (2016). "KELT-14b And KELT-15b: An Independent Discovery Of WASP-122b And A New Hot Jupiter". Astronomical Journal. Volume 151, Issue 6. 138 DOI: 10.3847/0004-6256/151/6/138 https://works.swarthmore.edu/fac-physics/286 This work is brought to you for free by Swarthmore College Libraries' Works. It has been accepted for inclusion in Physics & Astronomy Faculty Works by an authorized administrator of Works. For more information, please contact [email protected]. Authors J. E. Rodriguez, K. D. Colón, K. G. Stassun, D. Wright, P. A. Cargile, D. Bayliss, J. Pepper, K. A. Collins, R.
    [Show full text]
  • Filter Performance Comparisons for Some Common Nebulae
    Filter Performance Comparisons For Some Common Nebulae By Dave Knisely Light Pollution and various “nebula” filters have been around since the late 1970’s, and amateurs have been using them ever since to bring out detail (and even some objects) which were difficult to impossible to see before in modest apertures. When I started using them in the early 1980’s, specific information about which filter might work on a given object (or even whether certain filters were useful at all) was often hard to come by. Even those accounts that were available often had incomplete or inaccurate information. Getting some observational experience with the Lumicon line of filters helped, but there were still some unanswered questions. I wondered how the various filters would rank on- average against each other for a large number of objects, and whether there was a “best overall” filter. In particular, I also wondered if the much-maligned H-Beta filter was useful on more objects than the two or three targets most often mentioned in publications. In the summer of 1999, I decided to begin some more comprehensive observations to try and answer these questions and determine how to best use these filters overall. I formulated a basic survey covering a moderate number of emission and planetary nebulae to obtain some statistics on filter performance to try to address the following questions: 1. How do the various filter types compare as to what (on average) they show on a given nebula? 2. Is there one overall “best” nebula filter which will work on the largest number of objects? 3.
    [Show full text]
  • Successful Observing Sessions HOWL-EEN FUN Kepler’S Supernova Remnant Harvard’S Plate Project and Women Computers
    Published by the Astronomical League Vol. 69, No. 4 September 2017 Successful Observing Sessions HOWL-EEN FUN Kepler’s Supernova Remnant Harvard’s Plate Project and Women Computers T HE ASTRONOMICAL LEAGUE 1 he 1,396th entry in John the way to HR 8281, is the Dreyer’s Index Catalogue of Elephant’s Trunk Nebula. The T Nebulae and Clusters of left (east) edge of the trunk Stars is associated with a DEEP-SKY OBJECTS contains bright, hot, young galactic star cluster contained stars, emission nebulae, within a large region of faint reflection nebulae, and dark nebulosity, and a smaller region THE ELEPHANT’S TRUNK NEBULA nebulae worth exploring with an within it called the Elephant’s 8-inch or larger telescope. Trunk Nebula. In general, this By Dr. James R. Dire, Kauai Educational Association for Science & Astronomy Other features that are an entire region is absolute must to referred to by the check out in IC pachyderm 1396 are the proboscis phrase. many dark IC 1396 resides nebulae. Probably in the constellation the best is Cepheus and is Barnard 161. This located 2,400 light- dark nebula is years from Earth. located 15 To find IC 1396, arcminutes north start at Alpha of SAO 33652. Cephei, a.k.a. The nebula Alderamin, and go measures 5 by 2.5 five degrees arcminutes in southeast to the size. The nebula is fourth-magnitude very dark. Myriad red star Mu Cephei. Milky Way stars Mu Cephei goes by surround the the Arabic name nebula, but none Erakis. It is also can be seen in called Herschel’s this small patch of Garnet Star, after the sky.
    [Show full text]
  • Wynyard Planetarium & Observatory a Autumn Observing Notes
    Wynyard Planetarium & Observatory A Autumn Observing Notes Wynyard Planetarium & Observatory PUBLIC OBSERVING – Autumn Tour of the Sky with the Naked Eye CASSIOPEIA Look for the ‘W’ 4 shape 3 Polaris URSA MINOR Notice how the constellations swing around Polaris during the night Pherkad Kochab Is Kochab orange compared 2 to Polaris? Pointers Is Dubhe Dubhe yellowish compared to Merak? 1 Merak THE PLOUGH Figure 1: Sketch of the northern sky in autumn. © Rob Peeling, CaDAS, 2007 version 1.2 Wynyard Planetarium & Observatory PUBLIC OBSERVING – Autumn North 1. On leaving the planetarium, turn around and look northwards over the roof of the building. Close to the horizon is a group of stars like the outline of a saucepan with the handle stretching to your left. This is the Plough (also called the Big Dipper) and is part of the constellation Ursa Major, the Great Bear. The two right-hand stars are called the Pointers. Can you tell that the higher of the two, Dubhe is slightly yellowish compared to the lower, Merak? Check with binoculars. Not all stars are white. The colour shows that Dubhe is cooler than Merak in the same way that red-hot is cooler than white- hot. 2. Use the Pointers to guide you upwards to the next bright star. This is Polaris, the Pole (or North) Star. Note that it is not the brightest star in the sky, a common misconception. Below and to the left are two prominent but fainter stars. These are Kochab and Pherkad, the Guardians of the Pole. Look carefully and you will notice that Kochab is slightly orange when compared to Polaris.
    [Show full text]
  • The Midnight Sky: Familiar Notes on the Stars and Planets, Edward Durkin, July 15, 1869 a Good Way to Start – Find North
    The expression "dog days" refers to the period from July 3 through Aug. 11 when our brightest night star, SIRIUS (aka the dog star), rises in conjunction* with the sun. Conjunction, in astronomy, is defined as the apparent meeting or passing of two celestial bodies. TAAS Fabulous Fifty A program for those new to astronomy Friday Evening, July 20, 2018, 8:00 pm All TAAS and other new and not so new astronomers are welcome. What is the TAAS Fabulous 50 Program? It is a set of 4 meetings spread across a calendar year in which a beginner to astronomy learns to locate 50 of the most prominent night sky objects visible to the naked eye. These include stars, constellations, asterisms, and Messier objects. Methodology 1. Meeting dates for each season in year 2018 Winter Jan 19 Spring Apr 20 Summer Jul 20 Fall Oct 19 2. Locate the brightest and easiest to observe stars and associated constellations 3. Add new prominent constellations for each season Tonight’s Schedule 8:00 pm – We meet inside for a slide presentation overview of the Summer sky. 8:40 pm – View night sky outside The Midnight Sky: Familiar Notes on the Stars and Planets, Edward Durkin, July 15, 1869 A Good Way to Start – Find North Polaris North Star Polaris is about the 50th brightest star. It appears isolated making it easy to identify. Circumpolar Stars Polaris Horizon Line Albuquerque -- 35° N Circumpolar Stars Capella the Goat Star AS THE WORLD TURNS The Circle of Perpetual Apparition for Albuquerque Deneb 1 URSA MINOR 2 3 2 URSA MAJOR & Vega BIG DIPPER 1 3 Draco 4 Camelopardalis 6 4 Deneb 5 CASSIOPEIA 5 6 Cepheus Capella the Goat Star 2 3 1 Draco Ursa Minor Ursa Major 6 Camelopardalis 4 Cassiopeia 5 Cepheus Clock and Calendar A single map of the stars can show the places of the stars at different hours and months of the year in consequence of the earth’s two primary movements: Daily Clock The rotation of the earth on it's own axis amounts to 360 degrees in 24 hours, or 15 degrees per hour (360/24).
    [Show full text]
  • The Hypergiants VY Canis Majoris, Eta Carinae, V766 Centauri and The
    Sixteenth Marcel Grossmann Meeting Contribution ID: 967 Type: Talk in the parallel session The hypergiants VY Canis Majoris, Eta Carinae, V766 Centauri and the red supergiants Betelgeuse, Antares and Aldebaran in the 2.5K SGQ AAVSO database Thursday, 8 July 2021 16:35 (7 minutes) I observe variable stars since 1997. The “candidacy” of Mira Ceti as Betlehem Star because close to Jupiter- Saturn triple conjunction of 6-7 b.C. started at Pontifical University of Lateran and continued in Yale (2001- 2004). Maxima correlation function ruled out Mira for having two consecutive bright maxima, but this prop- erty was confirmed in the “oldest” Myra-type: R Leonis, R Hydrae and Chi Cygni, from their almostfour- century-long lightcurves. To a bright maximum normally a dim one follows, as the correlation function of their consecutive maxima shows. These studies were supported by historical and personal visual observations. Since 2011 I observe firstmag- nitude variable stars, with airmass correction to reach 0.01 magnitudes accuracy with naked eye. AAVSO observer Sebastian Otero first claimed this accuracy, as for NovaCentauri 2013, observed by me fromPorto Alegre and Rio de Janeiro. Betelgeuse’s 801 observations in 10 years, include the deep minimum of 2020. My SGQ contributions to AAVSO-database, paralleled with Betelgeuse’s V-band measurements, help to define the “personal equations” present in all 25M visual observations before CCD era (1911-on) going back to 1893 for Betelgeuse. The temporal extension of lightcurves is crucial to understand the stellar behaviour. More complicate cases are Antares and Aldebaran, less variable and with distant comparison stars.
    [Show full text]
  • On Massive Dust Clumps in the Envelope of the Red Supergiant VY Canis Majoris
    Astronomy & Astrophysics manuscript no. VYCMAclumps_CONTI_May2019 c ESO 2019 July 2, 2019 On massive dust clumps in the envelope of the red supergiant VY Canis Majoris ? T. Kaminski´ Center for Astrophysics | Harvard & Smithsonian, Smithsonian Astrophysical Observatory, e-mail: [email protected] Received; accepted ABSTRACT The envelope of the red supergiant VY CMa has long been considered an extreme example of episodic mass loss that is possibly taking place in other cool and massive evolved stars. Recent (sub-)millimeter observations of the envelope revealed the presence of massive dusty clumps within 800 mas from the star which reinforce the picture of drastic mass-loss phenomena in VY CMa. We present new ALMA observations at an angular resolution of 0.100and at an unprecedented sensitivity that reveal further details about the dusty clumps. We resolve more discrete features and identify a submillimeter counterpart of a more distant Clump SW known from visual observations. The brightest clump, named C, is marginally resolved in the observations. Gas seen against the resolved continuum emission of clump C produces a molecular spectrum in absorption, in lines of mainly sulfur-bearing species. Except for SW Clump, no molecular emission is found to be associated with the dusty clumps and we propose that the dusty structures have an atypically low gas content. We attempt to reproduce the properties of the dusty clumps through three-dimensional radiative-transfer modeling. Although a clump configuration explaining the observations is found, it is not unique. A very high optical depth of all clumps to the stellar radiation make the modeling very challenging and requires unrealistically high dust masses for one of them.
    [Show full text]
  • Winter Observing Notes
    Wynyard Planetarium & Observatory Winter Observing Notes Wynyard Planetarium & Observatory PUBLIC OBSERVING – Winter Tour of the Sky with the Naked Eye NGC 457 CASSIOPEIA eta Cas Look for Notice how the constellations 5 the ‘W’ swing around Polaris during shape the night Is Dubhe yellowish compared 2 Polaris to Merak? Dubhe 3 Merak URSA MINOR Kochab 1 Is Kochab orange Pherkad compared to Polaris? THE PLOUGH 4 Mizar Alcor Figure 1: Sketch of the northern sky in winter. North 1. On leaving the planetarium, turn around and look northwards over the roof of the building. To your right is a group of stars like the outline of a saucepan standing up on it’s handle. This is the Plough (also called the Big Dipper) and is part of the constellation Ursa Major, the Great Bear. The top two stars are called the Pointers. Check with binoculars. Not all stars are white. The colour shows that Dubhe is cooler than Merak in the same way that red-hot is cooler than white-hot. 2. Use the Pointers to guide you to the left, to the next bright star. This is Polaris, the Pole (or North) Star. Note that it is not the brightest star in the sky, a common misconception. Below and to the right are two prominent but fainter stars. These are Kochab and Pherkad, the Guardians of the Pole. Look carefully and you will notice that Kochab is slightly orange when compared to Polaris. Check with binoculars. © Rob Peeling, CaDAS, 2007 version 2.0 Wynyard Planetarium & Observatory PUBLIC OBSERVING – Winter Polaris, Kochab and Pherkad mark the constellation Ursa Minor, the Little Bear.
    [Show full text]
  • Educator's Guide: Orion
    Legends of the Night Sky Orion Educator’s Guide Grades K - 8 Written By: Dr. Phil Wymer, Ph.D. & Art Klinger Legends of the Night Sky: Orion Educator’s Guide Table of Contents Introduction………………………………………………………………....3 Constellations; General Overview……………………………………..4 Orion…………………………………………………………………………..22 Scorpius……………………………………………………………………….36 Canis Major…………………………………………………………………..45 Canis Minor…………………………………………………………………..52 Lesson Plans………………………………………………………………….56 Coloring Book…………………………………………………………………….….57 Hand Angles……………………………………………………………………….…64 Constellation Research..…………………………………………………….……71 When and Where to View Orion…………………………………….……..…77 Angles For Locating Orion..…………………………………………...……….78 Overhead Projector Punch Out of Orion……………………………………82 Where on Earth is: Thrace, Lemnos, and Crete?.............................83 Appendix………………………………………………………………………86 Copyright©2003, Audio Visual Imagineering, Inc. 2 Legends of the Night Sky: Orion Educator’s Guide Introduction It is our belief that “Legends of the Night sky: Orion” is the best multi-grade (K – 8), multi-disciplinary education package on the market today. It consists of a humorous 24-minute show and educator’s package. The Orion Educator’s Guide is designed for Planetarians, Teachers, and parents. The information is researched, organized, and laid out so that the educator need not spend hours coming up with lesson plans or labs. This has already been accomplished by certified educators. The guide is written to alleviate the fear of space and the night sky (that many elementary and middle school teachers have) when it comes to that section of the science lesson plan. It is an excellent tool that allows the parents to be a part of the learning experience. The guide is devised in such a way that there are plenty of visuals to assist the educator and student in finding the Winter constellations.
    [Show full text]
  • A Basic Requirement for Studying the Heavens Is Determining Where In
    Abasic requirement for studying the heavens is determining where in the sky things are. To specify sky positions, astronomers have developed several coordinate systems. Each uses a coordinate grid projected on to the celestial sphere, in analogy to the geographic coordinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth's equator) . Each coordinate system is named for its choice of fundamental plane. The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the one most closely related to the geographic coordinate system, because they use the same fun­ damental plane and the same poles. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles on to the celest ial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate systems: the geographic system is fixed to the Earth; it rotates as the Earth does . The equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but of course it's really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec for short) . It measures the angle of an object above or below the celestial equator. The longitud inal angle is called the right ascension (RA for short).
    [Show full text]
  • An Interferometric Spectral-Line and Imaging Survey of VY Canis Majoris
    An Interferometric Spectral-Line and Imaging Survey of VY Canis Majoris in the 345 GHz Band T. Kami´nski1, C. A. Gottlieb2, K. H. Young2, K. M. Menten1, N. A. Patel2 [email protected] ABSTRACT A spectral line survey of the oxygen-rich red supergiant VY Canis Majoris was made between 279 and 355 GHz with the Submillimeter Array. Two hundred twenty three spectral features from 19 molecules (not counting isotopic species of some of them) were observed, including the rotational spectra of TiO, TiO2, and AlCl for the first time in this source. The parameters and an atlas of all spectral features is presented. Observations of each line with a synthesized beam of ∼0′′. 9, reveal the complex kinematics and morphology of the nebula surrounding VY CMa. Many of the molecules are observed in high lying rotational levels or in excited vibrational levels. From these, it was established that the main source of the submillimeter-wave continuum (dust) and the high excitation molecular gas (the star) are separated by about 0′′. 15. Apparent coincidences between the molecular gas observed with the SMA, and some of the arcs and knots observed at infrared wavelengths and in the optical scattered light by the Hubble Space Telescope are identified. The observations presented here provide important constraints on the molecular chemistry in oxygen-dominated circumstellar environments and a deeper picture of the complex circumstellar environment of VY CMa. Subject headings: astrochemistry – circumstellar matter – line: identification – stars: individual (VY CMa) – supergiants – surveys 1. Introduction Most recent studies of circumstellar envelopes with radio telescopes have focused on IRC+10◦216 (CWLeo), a nearby carbon star on the asymptotic giant branch (AGB; Patel et al.
    [Show full text]