W.M. Keck Observatory Annual Report 2009

Total Page:16

File Type:pdf, Size:1020Kb

W.M. Keck Observatory Annual Report 2009 W.M. Keck Observatory Annual Report 2009 aannual_report_2009.inddnnual_report_2009.indd 1 66/9/2010/9/2010 111:52:481:52:48 AAMM COVER: University of Hawai‘i photographer R. David Beales won Best in Show at the University Photographers Association of America, or UPAA, competition for his VISION December 2009 image, “Mauna Kea Summit,” showing A worldldd in whichw h all humankindhumanki is inspired and the W. M. Keck Observatory’s laser piercing the Hawaiian unitedun by the pursupursuituitit off knowkknowledge of the infi nite night sky. varietyarriety andannd rririchnessichnesc s of theh Universe. INSIDE COVER: Visiting astronomers in the remote operations facility at Waimea headquarters discuss details of their observing run. 3: Award winning architecture of Keck headquarters framed by early evening light and the pastoral beauty of MISSION Waimea. To advance the frontiers of astronomy and share our discoveries, inspiring the imagination of all. Observatory Groundbreaking: 1985 First light Keck I telescope: 1992 First light Keck II telescope: 1996 Headquarters location: Kamuela, Hawai’i, USA Management: California Association for Research in Astronomy Partner Institutions: California Institute of Technology (CIT/Caltech), Contents University of California (UC), 3 The Director’s Report National Aeronautics and Space Administration (NASA) 5 What Sets Keck Apart Observatory Director: Taft E. Armandroff 7 Discoveries 12 Finances Deputy Director: Hilton A. Lewis 17 The People of Keck FY2009 24 Education and Outreach Number of Full Time Employees: 117 Number of Observing Astronomers: 469 28 Science Bibliography Number of Keck Science Investigations: 405 Number of Refereed Articles: 260 Fiscal Year begins October 1 W.M. Keck Observatory Annual Report 2009 –2– aannual_report_2009.inddnnual_report_2009.indd 2 66/9/2010/9/2010 111:52:551:52:55 AAMM An Amazing Year of Discoveries THE DIRECTOR’S REPORT Dr. Taft E. Armandroff “ he year 2009 was the International Year of Astronomy, biologically or geologically active, fi nding variations in the commemorating two major astronomical achievements concentration of this organic molecule over both time and that took place 400 years ago: Galileo Galilei fi rst turned location. Mumma and his team continue to apply the Keck his simple refracting telescope toward the heavens, and telescopes, particularly our world leading adaptive optics in that same year Johannes Kepler published his book, system and NIRSPEC, a near-infrared echelle spectrograph, Astronomia Nova, describing the fi rst two laws of planetary to more precisely map these methane emissions and guide motion. further research to determine their source. How inspiring to consider what we have learned about the Another highlight of the year occurred in June 2009 when Universe since 1609 when the moons of Jupiter and the laws the Low Resolution Imaging Spectrograph (LRIS), one of physics came into focus. And how humbling to realize of Keck’s fi rst instruments and still our most popular and how many fundamental questions about the cosmos remain productive one, completed a major upgrade to its capabilities. to be answered through the science of astronomy. LRIS is a double spectrograph that obtains data in the red and blue regions of the electromagnetic spectrum simultaneously. It is the W.M. Keck Observatory’s role to answer these The entire red-side detector, electronics, and software were questions and over the past year we celebrated major replaced with state-of-the-art technology. milestones in both astronomical exploration and technology initiatives. It is my privilege to serve as the Director of the The red region upgrade has made LRIS the most sensitive Keck Observatory and to introduce the chronicling of these optical spectrograph in the world. With greater sensitivity achievements in the pages that follow. and lower noise, the instrument now gives Keck astronomers the capability to work on scientifi c problems that were One of the highlights of 2009 took place in January when a previously impossible and surpass observations that we could team of astronomers led by NASA’s Mike Mumma reported undertake before. Astronomers can observe more targets the fi rst defi nitive detection of methane in the atmosphere per night and yield more statistically robust results. Private of Mars. Described in detail in the Discoveries section of philanthropy was essential in realizing the success of the the Report, their research indicates the Red Planet is either LRIS upgrade project. –3– aannual_report_2009.inddnnual_report_2009.indd 3 66/9/2010/9/2010 111:53:151:53:15 AAMM OverOver the pastpaast yearyear,, Keckk ObsObservatorybse made great progress ABOVE: Observatory on twoo otherer multi-yearmultti-year instruminstrumentationi initiatives: Director Taft MOSFIRE,MOSFM FIRE, thethhe MultiMulltiti Object ObObjbject SpectrographSp for Infrared Armandroff and Deputy Director EExplorationxploratationion andan the next gegenerationeneratio Laser Guide Star Hilton Lewis. AdaptiveAdaptivAdA ve OpticsOpticcs (LGSGS AO) AOO) system for the Keck I telescope. Bothotthh MOSMOSFIREOSFIRFIRRE and thet new LLGS AO system are scheduled BELOW: A rare aerial foro integraintegrationation anandnd ccomcommissioningmmiss in fi scal 2010 and are view of majestic eagerlygerrlyly aantanticipatednticipatted by oour science community. Mauna Kea and the Observatories. In tthisis AnnuAnnualual RepReport you will meet some of the highly trained and dedicadedicated staff members responsible for maintaining and operating the Keck telescopes as well as deploying these technological innovations. Alongside these and other Keck professionals you will also be introduced to leaders from our astronomy community who are contributing by developing new instrumentation or participating in Observatory governance. And you will learn how in the International Year of Astronomy we continued the trend of increasing both the new science enabled is dramatic and the results published quality and quantity of our education and outreach activities over the past fi scal year by Keck’s astronomers are also and growing the number of our philanthropic supporters. quantifi ed in the Report. We are encouraged by the signifi cant interest in and support of our work by the public. In its short history, the twin ten-meter Keck telescopes have pushed Galileo’s fi rst concepts of astronomy to the Modern astronomy is a highly competitive and constantly extreme and brought the beauty, complexities and mysteries changing fi eld, and Keck Observatory continues to be of the cosmos within reach. As an organization we are honed as a powerful discovery machine with additions to proud of what we have accomplished not only in cutting- our telescope instrumentation and enhancements to our edge discoveries but also in training and inspiring the next adaptive optics systems. These technological enhancements generation of explorers. I thank our professional staff, our are complex and require signifi cant resources to design governing board and advisors, our philanthropic supporters, and build. As a private-public partnership, we rely on and our volunteers for all their contributions and for their “ grants from federal agencies and gifts from individuals and steadfast commitment to our continued leadership in this foundations to fund these pathfi nding developments. The amazing scientifi c enterprise. W.M. Keck Observatory Annual Report 2009 –4– aannual_report_2009.inddnnual_report_2009.indd 4 66/9/2010/9/2010 111:53:201:53:20 AAMM Welcome to the cutting edge of tomorrow… The twin 10-meter Keck Telescopes are the leading optical/infrared telescopes in the world and are dedicated to astronomical research 365 days/nights per year. Observing time on the Keck telescopes is highly prized and is divided each year among its partner institutions: the California Institute of Technology, the University of California and NASA, as well as the University of Hawai’i. The broader astronomical community has access to the telescopes through partnerships with the National Science Foundation and NASA. Recognized as the most scientifi cally productive observatory in history, Keck Observatory has contributed to all areas of astronomy and astrophysics. Keck’s legacy of exploration includes the discovery of exoplanets; the study of how planets, stars and galaxies form; the nature of black holes; and the chemical composition and evolution of the Universe. Beyond offering the largest light collection mirrors on the planet, the Keck telescopes host a complete suite of nine state-of-the-art observing instruments to collect and analyze astronomical data with unprecedented power and precision. Keck is a world leader in the fi eld of adaptive optics, a breakthrough technology that removes the distortions caused by the turbulence in the Earth’s atmosphere and provides image clarity of cosmic targets that rivals those of the Hubble Space Telescope. Made possible by grants from the W. M. Keck Foundation, the Observatory today is a private 501(c)3 non-profi t organization and depends upon competitive grants and philanthropy to sustain its frontier research capabilities. W.M. Keck Observatory Annual Report 2009 –5– aannual_report_2009.inddnnual_report_2009.indd 5 66/9/2010/9/2010 111:53:411:53:41 AAMM Cosmic Vision W. M. Keck Observatory Keck Observatory Advancement Keck Observatory Science Board of Directors Advisory Council Steering Committee George Blumenthal, Chair Sanford Robertson, Chair, Jean Brodie, Co-Chair Edward Stolper, Vice-Chair and Jeanne Robertson Chris Martin,
Recommended publications
  • Lurking in the Shadows: Wide-Separation Gas Giants As Tracers of Planet Formation
    Lurking in the Shadows: Wide-Separation Gas Giants as Tracers of Planet Formation Thesis by Marta Levesque Bryan In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena, California 2018 Defended May 1, 2018 ii © 2018 Marta Levesque Bryan ORCID: [0000-0002-6076-5967] All rights reserved iii ACKNOWLEDGEMENTS First and foremost I would like to thank Heather Knutson, who I had the great privilege of working with as my thesis advisor. Her encouragement, guidance, and perspective helped me navigate many a challenging problem, and my conversations with her were a consistent source of positivity and learning throughout my time at Caltech. I leave graduate school a better scientist and person for having her as a role model. Heather fostered a wonderfully positive and supportive environment for her students, giving us the space to explore and grow - I could not have asked for a better advisor or research experience. I would also like to thank Konstantin Batygin for enthusiastic and illuminating discussions that always left me more excited to explore the result at hand. Thank you as well to Dimitri Mawet for providing both expertise and contagious optimism for some of my latest direct imaging endeavors. Thank you to the rest of my thesis committee, namely Geoff Blake, Evan Kirby, and Chuck Steidel for their support, helpful conversations, and insightful questions. I am grateful to have had the opportunity to collaborate with Brendan Bowler. His talk at Caltech my second year of graduate school introduced me to an unexpected population of massive wide-separation planetary-mass companions, and lead to a long-running collaboration from which several of my thesis projects were born.
    [Show full text]
  • BRAS Newsletter August 2013
    www.brastro.org August 2013 Next meeting Aug 12th 7:00PM at the HRPO Dark Site Observing Dates: Primary on Aug. 3rd, Secondary on Aug. 10th Photo credit: Saturn taken on 20” OGS + Orion Starshoot - Ben Toman 1 What's in this issue: PRESIDENT'S MESSAGE....................................................................................................................3 NOTES FROM THE VICE PRESIDENT ............................................................................................4 MESSAGE FROM THE HRPO …....................................................................................................5 MONTHLY OBSERVING NOTES ....................................................................................................6 OUTREACH CHAIRPERSON’S NOTES .........................................................................................13 MEMBERSHIP APPLICATION .......................................................................................................14 2 PRESIDENT'S MESSAGE Hi Everyone, I hope you’ve been having a great Summer so far and had luck beating the heat as much as possible. The weather sure hasn’t been cooperative for observing, though! First I have a pretty cool announcement. Thanks to the efforts of club member Walt Cooney, there are 5 newly named asteroids in the sky. (53256) Sinitiere - Named for former BRAS Treasurer Bob Sinitiere (74439) Brenden - Named for founding member Craig Brenden (85878) Guzik - Named for LSU professor T. Greg Guzik (101722) Pursell - Named for founding member Wally Pursell
    [Show full text]
  • Paul Sykes Lecture – Sat, Jan 27 @ 7:30Pm Ice on Mercury, Featuring Dr
    NOVANEWSLETTEROFTHEVANCOUVERCENTRERASC VOLUME2018ISSUE1JANUARYFEBRUARY2018 Paul Sykes Lecture – Sat, Jan 27 @ 7:30pm Ice on Mercury, Featuring Dr. Nancy Chabot of Johns Hopkins University SFU Burnaby Campus, Room SWH 10081 Even though Mercury is the Dr. Nancy L. Chabot is a and Case Western Reserve Uni- planet closest to the Sun, there planetary scientist at the Johns versity. She has been a mem- are places at its poles that never Hopkins Applied Physics Labo- ber of five field teams with the receive sunlight and are very ratory (apl). She received an Antarctic Search for Meteorites cold—cold enough to hold wa- (ansmet) program and served ter ice! In this presentation, Dr. as the Instrument Scientist for Chabot will show the multiple the Mercury Dual Imaging Sys- lines of evidence that regions tem (mdis) on the messenger near Mercury’s poles hold water mission. Her research interests ice—from the first discovery involve understanding the evo- by Earth-based radar observa- lution of rocky planetary bod- tions to multiple data sets from ies in the Solar System, and at nasa’s messenger spacecraft, apl she oversees an experimen- the first spacecraft ever to or- tal geochemistry laboratory bit the planet Mercury. These that is used to conduct experi- combined results suggest that ments related to this topic. Dr. Mercury’s polar ice deposits Chabot has served as an Associ- are substantial, perhaps compa- ate Editor for the journal Mete- rable to the amount of water in oritics and Planetary Science, Lake Ontario! Where did the chair of nasa’s Small Bodies ice come from and how did it undergraduate degree in physics Assessment Group, a member get there? Dr.
    [Show full text]
  • Maio - 2017 Francisco Jânio Cavalcante
    UNIVERSIDADE FEDERAL DO RIO GRANDE DO NORTE CENTRO DE CIÊNCIAS EXATAS E DA TERRA DEPARTAMENTO DE FÍSICA TEÓRICA E EXPERIMENTAL PROGRAMA DE PÓS-GRADUAÇÃO EM FÍSICA EVOLUÇÃO DO ÍNDICE DE FREIO MAGNÉTICO PARA ESTRELAS DO TIPO SOLAR FRANCISCO JÂNIO CAVALCANTE NATAL (RN) MAIO - 2017 FRANCISCO JÂNIO CAVALCANTE EVOLUÇÃO DO ÍNDICE DE FREIO MAGNÉTICO PARA ESTRELAS DO TIPO SOLAR Tese de Doutorado apresentada ao Programa de Pós-Graduação em Física do Departamento de Física Teórica e Experimental da Universidade Federal do Rio Grande do Norte como requisito parcial para a obtenção do grau de Doutor em Física. Orientador: Dr. Daniel Brito de Freitas NATAL (RN) MAIO - 2017 UFRN / Biblioteca Central Zila Mamede Catalogação da Publicação na Fonte Cavalcante, Francisco Jânio. Evolução do índice de freio magnético para estrelas do tipo solar / Francisco Jânio Cavalcante. - 2017. 166 f. : il. Tese (doutorado) - Universidade Federal do Rio Grande do Norte, Centro de Ciências Exatas e da Terra, Programa de Pós-Graduação em Física. Natal, RN, 2017. Orientador: Prof. Dr. Daniel Brito de Freitas. 1. Rotação estelar - Tese. 2. Freio magnético - Tese. 3. Distribuição e estatística - Tese. I. Freitas, Daniel Brito de. II. Título. RN/UF/BCZM CDU 524.3 Para Pessoas Especiais: A minha avó, minha mãe e minha namorada Ester Saraiva da Silva (in memorian) Cleta Carneiro Cavalcante Simone Santos Martins Agradecimentos Agradeço ao bom e generoso Deus, quem me deu muitas coisas no decorrer da minha vida. Deu-me compreensão e amparo nos momento de aflição e tristeza, saúde para continuar nesta caminhada. Ofereceu-me sua luz no momento em que a escuridão sufocava meu espírito.
    [Show full text]
  • Arxiv:1305.7264V2 [Astro-Ph.EP] 21 Apr 2014 Spain
    Draft version September 18, 2018 Preprint typeset using LATEX style emulateapj v. 08/22/09 THE MOVING GROUP TARGETS OF THE SEEDS HIGH-CONTRAST IMAGING SURVEY OF EXOPLANETS AND DISKS: RESULTS AND OBSERVATIONS FROM THE FIRST THREE YEARS Timothy D. Brandt1, Masayuki Kuzuhara2, Michael W. McElwain3, Joshua E. Schlieder4, John P. Wisniewski5, Edwin L. Turner1,6, J. Carson7,4, T. Matsuo8, B. Biller4, M. Bonnefoy4, C. Dressing9, M. Janson1, G. R. Knapp1, A. Moro-Mart´ın10, C. Thalmann11, T. Kudo12, N. Kusakabe13, J. Hashimoto13,5, L. Abe14, W. Brandner4, T. Currie15, S. Egner12, M. Feldt4, T. Golota12, M. Goto16, C. A. Grady3,17, O. Guyon12, Y. Hayano12, M. Hayashi18, S. Hayashi12, T. Henning4, K. W. Hodapp19, M. Ishii12, M. Iye13, R. Kandori13, J. Kwon13,22, K. Mede18, S. Miyama20, J.-I. Morino13, T. Nishimura12, T.-S. Pyo12, E. Serabyn21, T. Suenaga22, H. Suto13, R. Suzuki13, M. Takami23, Y. Takahashi18, N. Takato12, H. Terada12, D. Tomono12, M. Watanabe24, T. Yamada25, H. Takami12, T. Usuda12, M. Tamura13,18 Draft version September 18, 2018 ABSTRACT We present results from the first three years of observations of moving group targets in the SEEDS high-contrast imaging survey of exoplanets and disks using the Subaru telescope. We achieve typical contrasts of ∼105 at 100 and ∼106 beyond 200 around 63 proposed members of nearby kinematic moving groups. We review each of the kinematic associations to which our targets belong, concluding that five, β Pictoris (∼20 Myr), AB Doradus (∼100 Myr), Columba (∼30 Myr), Tucana-Horogium (∼30 Myr), and TW Hydrae (∼10 Myr), are sufficiently well-defined to constrain the ages of individual targets.
    [Show full text]
  • Naming the Extrasolar Planets
    Naming the extrasolar planets W. Lyra Max Planck Institute for Astronomy, K¨onigstuhl 17, 69177, Heidelberg, Germany [email protected] Abstract and OGLE-TR-182 b, which does not help educators convey the message that these planets are quite similar to Jupiter. Extrasolar planets are not named and are referred to only In stark contrast, the sentence“planet Apollo is a gas giant by their assigned scientific designation. The reason given like Jupiter” is heavily - yet invisibly - coated with Coper- by the IAU to not name the planets is that it is consid- nicanism. ered impractical as planets are expected to be common. I One reason given by the IAU for not considering naming advance some reasons as to why this logic is flawed, and sug- the extrasolar planets is that it is a task deemed impractical. gest names for the 403 extrasolar planet candidates known One source is quoted as having said “if planets are found to as of Oct 2009. The names follow a scheme of association occur very frequently in the Universe, a system of individual with the constellation that the host star pertains to, and names for planets might well rapidly be found equally im- therefore are mostly drawn from Roman-Greek mythology. practicable as it is for stars, as planet discoveries progress.” Other mythologies may also be used given that a suitable 1. This leads to a second argument. It is indeed impractical association is established. to name all stars. But some stars are named nonetheless. In fact, all other classes of astronomical bodies are named.
    [Show full text]
  • Multiple Star Systems Observed with Corot and Kepler
    Multiple star systems observed with CoRoT and Kepler John Southworth Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK Abstract. The CoRoT and Kepler satellites were the first space platforms designed to perform high-precision photometry for a large number of stars. Multiple systems dis- play a wide variety of photometric variability, making them natural benefactors of these missions. I review the work arising from CoRoT and Kepler observations of multiple sys- tems, with particular emphasis on eclipsing binaries containing giant stars, pulsators, triple eclipses and/or low-mass stars. Many more results remain untapped in the data archives of these missions, and the future holds the promise of K2, TESS and PLATO. 1 Introduction The CoRoT and Kepler satellites represent the first generation of astronomical space missions capable of large-scale photometric surveys. The large quantity – and exquisite quality – of the data they pro- vided is in the process of revolutionising stellar and planetary astrophysics. In this review I highlight the immense variety of the scientific results from these concurrent missions, as well as the context provided by their precursors and implications for their successors. CoRoT was led by CNES and ESA, launched on 2006/12/27,and retired in June 2013 after an irre- trievable computer failure in November 2012. It performed 24 observing runs, each lasting between 21 and 152days, with a field of viewof 2×1.3◦ ×1.3◦, obtaining light curves of 163000 stars [42]. Kepler was a NASA mission, launched on 2009/03/07and suffering a critical pointing failure on 2013/05/11. It observed the same 105deg2 sky area for its full mission duration, obtaining high-precision light curves of approximately 191000 stars.
    [Show full text]
  • SEPTEMBER 2014 OT H E D Ebn V E R S E R V ESEPTEMBERR 2014
    THE DENVER OBSERVER SEPTEMBER 2014 OT h e D eBn v e r S E R V ESEPTEMBERR 2014 FROM THE INSIDE LOOKING OUT Calendar Taken on July 25th in San Luis State Park near the Great Sand Dunes in Colorado, Jeff made this image of the Milky Way during an overnight camping stop on the way to Santa Fe, NM. It was taken with a Canon 2............................. First quarter moon 60D camera, an EFS 15-85 lens, using an iOptron SkyTracker. It is a single frame, with no stacking or dark/ 8.......................................... Full moon bias frames, at ISO 1600 for two minutes. Visible in this south-facing photograph is Sagittarius, and the 14............ Aldebaran 1.4˚ south of moon Dark Horse Nebula inside of the Milky Way. He processed the image in Adobe Lightroom. Image © Jeff Tropeano 15............................ Last quarter moon 22........................... Autumnal Equinox 24........................................ New moon Inside the Observer SEPTEMBER SKIES by Dennis Cochran ygnus the Swan dives onto center stage this other famous deep-sky object is the Veil Nebula, President’s Message....................... 2 C month, almost overhead. Leading the descent also known as the Cygnus Loop, a supernova rem- is the nose of the swan, the star known as nant so large that its separate arcs were known Society Directory.......................... 2 Albireo, a beautiful multi-colored double. One and named before it was found to be one wide Schedule of Events......................... 2 wonders if Albireo has any planets from which to wisp that came out of a single star. The Veil is see the pair up-close.
    [Show full text]
  • Download This Article in PDF Format
    A&A 562, A92 (2014) Astronomy DOI: 10.1051/0004-6361/201321493 & c ESO 2014 Astrophysics Li depletion in solar analogues with exoplanets Extending the sample, E. Delgado Mena1,G.Israelian2,3, J. I. González Hernández2,3,S.G.Sousa1,2,4, A. Mortier1,4,N.C.Santos1,4, V. Zh. Adibekyan1, J. Fernandes5, R. Rebolo2,3,6,S.Udry7, and M. Mayor7 1 Centro de Astrofísica, Universidade do Porto, Rua das Estrelas, 4150-762 Porto, Portugal e-mail: [email protected] 2 Instituto de Astrofísica de Canarias, C/ Via Lactea s/n, 38200 La Laguna, Tenerife, Spain 3 Departamento de Astrofísica, Universidad de La Laguna, 38205 La Laguna, Tenerife, Spain 4 Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal 5 CGUC, Department of Mathematics and Astronomical Observatory, University of Coimbra, 3049 Coimbra, Portugal 6 Consejo Superior de Investigaciones Científicas, CSIC, Spain 7 Observatoire de Genève, Université de Genève, 51 ch. des Maillettes, 1290 Sauverny, Switzerland Received 18 March 2013 / Accepted 25 November 2013 ABSTRACT Aims. We want to study the effects of the formation of planets and planetary systems on the atmospheric Li abundance of planet host stars. Methods. In this work we present new determinations of lithium abundances for 326 main sequence stars with and without planets in the Teff range 5600–5900 K. The 277 stars come from the HARPS sample, the remaining targets were observed with a variety of high-resolution spectrographs. Results. We confirm significant differences in the Li distribution of solar twins (Teff = T ± 80 K, log g = log g ± 0.2and[Fe/H] = [Fe/H] ±0.2): the full sample of planet host stars (22) shows Li average values lower than “single” stars with no detected planets (60).
    [Show full text]
  • Sky Notes by Neil Bone 2005 August & September
    Sky notes by Neil Bone 2005 August & September below Castor and Pollux. Mercury is soon ing June and July, it is still quite possible that Sun and Moon lost from view again, arriving at superior con- noctilucent clouds (NLC) could be seen into junction beyond the Sun on September 18. early August, particularly by observers at The Sun continues its southerly progress along Venus continues its rather unfavourable more northerly locations. Quite how late into the ecliptic, reaching the autumnal equinox showing as an ‘Evening Star’. Although it August NLC can be seen remains to be deter- position at 22h 23m Universal Time (UT = pulls out to over 40° elongation east of the mined: there have been suggestions that the GMT; BST minus 1 hour) on September 22. Sun during September, Venus is also heading visibility period has become longer in recent At that precise time, the centre of the solar southwards, and as a result its setting-time years. Observational reports will be welcomed disk is positioned at the intersection between after the Sun remains much the same − barely by the Aurora Section. the celestial equator and the ecliptic, the latter an hour − during this interval. Although bright While declining sunspot activity makes great circle on the sky being inclined by 23.5° at magnitude −4, Venus will be quite tricky major aurorae extending to lower latitudes to the former. Calendrical autumn begins at the to catch in the early twilight: viewing cir- less likely, the appearance of coronal holes equinox, but amateur astronomers might more cumstances don’t really improve until the in the latter parts of the cycle does bring the readily follow meteorological timing, wherein closing weeks of 2005.
    [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]
  • By John Dobson San Francisco Sidewalk Astronomers
    the newsletter of the QUEEN ELIZABET H PLANETARIUM SUMMER 198 0 and the EDMONTON CENTRE, RAS C 50$ y SPECIAL TELESCOP E ISSU E NOW PLAYIN G AT QUEEN PlANETARiUM A spectacular celestial event was witnessed by th e ancien t Sumeria n civilizatio n an d ""VELA recorded i n thei r mysteriou s cuneifor m writing. Wha t wa s it ? Th e Vela Apparition APPARITION blends archaeolog y wit h astronom y i n a search for the origins o f civilzation. 3 P M and 8 P M Daily one The night sk y i s a fascinating -realm. Stars, nebulae, an d galaxie s ar e scattere d SUMMER'S throughout infinity . Join us for a tour of the sights o f th e summertim e sky . Rela x and NIGHT enjoy an evening at the Planetarium durin g One Summer's Night. 9PM Dail y A special show for special people age 3 to 7. A Fantasy O f Stars chronicle s th e FANTASY adventures o f Harol d th e Her o a s h e ventures int o th e nigh t sk y t o mee t th e constellations. A reduced admission of only o, STARS 50C for everyon e applies to thi s 3 5 minute live presentation. For more •information , „ , please phone th re Planetariu•• , , 1:3m at 0 P M Wed . and Sun . 455-0119 Vol. 2 5 No . 1 0 StOPCll SUMMER 198 0 Have Telescopes , Will Travel JOH N DOBSO N 1 0 People came from all over the city by bus, by car, by bicycle, and by foot to look through the telescope.
    [Show full text]