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FY08 Technical Papers by GSMTPO Staff
AURA/NOAO ANNUAL REPORT FY 2008 Submitted to the National Science Foundation July 23, 2008 Revised as Complete and Submitted December 23, 2008 NGC 660, ~13 Mpc from the Earth, is a peculiar, polar ring galaxy that resulted from two galaxies colliding. It consists of a nearly edge-on disk and a strongly warped outer disk. Image Credit: T.A. Rector/University of Alaska, Anchorage NATIONAL OPTICAL ASTRONOMY OBSERVATORY NOAO ANNUAL REPORT FY 2008 Submitted to the National Science Foundation December 23, 2008 TABLE OF CONTENTS EXECUTIVE SUMMARY ............................................................................................................................. 1 1 SCIENTIFIC ACTIVITIES AND FINDINGS ..................................................................................... 2 1.1 Cerro Tololo Inter-American Observatory...................................................................................... 2 The Once and Future Supernova η Carinae...................................................................................................... 2 A Stellar Merger and a Missing White Dwarf.................................................................................................. 3 Imaging the COSMOS...................................................................................................................................... 3 The Hubble Constant from a Gravitational Lens.............................................................................................. 4 A New Dwarf Nova in the Period Gap............................................................................................................ -
A Hot Subdwarf-White Dwarf Super-Chandrasekhar Candidate
A hot subdwarf–white dwarf super-Chandrasekhar candidate supernova Ia progenitor Ingrid Pelisoli1,2*, P. Neunteufel3, S. Geier1, T. Kupfer4,5, U. Heber6, A. Irrgang6, D. Schneider6, A. Bastian1, J. van Roestel7, V. Schaffenroth1, and B. N. Barlow8 1Institut fur¨ Physik und Astronomie, Universitat¨ Potsdam, Haus 28, Karl-Liebknecht-Str. 24/25, D-14476 Potsdam-Golm, Germany 2Department of Physics, University of Warwick, Coventry, CV4 7AL, UK 3Max Planck Institut fur¨ Astrophysik, Karl-Schwarzschild-Straße 1, 85748 Garching bei Munchen¨ 4Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106, USA 5Texas Tech University, Department of Physics & Astronomy, Box 41051, 79409, Lubbock, TX, USA 6Dr. Karl Remeis-Observatory & ECAP, Astronomical Institute, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Sternwartstr. 7, 96049 Bamberg, Germany 7Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA 8Department of Physics and Astronomy, High Point University, High Point, NC 27268, USA *[email protected] ABSTRACT Supernova Ia are bright explosive events that can be used to estimate cosmological distances, allowing us to study the expansion of the Universe. They are understood to result from a thermonuclear detonation in a white dwarf that formed from the exhausted core of a star more massive than the Sun. However, the possible progenitor channels leading to an explosion are a long-standing debate, limiting the precision and accuracy of supernova Ia as distance indicators. Here we present HD 265435, a binary system with an orbital period of less than a hundred minutes, consisting of a white dwarf and a hot subdwarf — a stripped core-helium burning star. -
The Earth Observer. July
National Aeronautics and Space Administration The Earth Observer. July - August 2012. Volume 24, Issue 4. Editor’s Corner Steve Platnick obser ervth EOS Senior Project Scientist The joint NASA–U.S. Geological Survey (USGS) Landsat program celebrated a major milestone on July 23 with the 40th anniversary of the launch of the Landsat-1 mission—then known as the Earth Resources and Technology Satellite (ERTS). Landsat-1 was the first in a series of seven Landsat satellites launched to date. At least one Landsat satellite has been in operation at all times over the past four decades providing an uninter- rupted record of images of Earth’s land surface. This has allowed researchers to observe patterns of land use from space and also document how the land surface is changing with time. Numerous operational applications of Landsat data have also been developed, leading to improved management of resources and informed land use policy decisions. (The image montage at the bottom of this page shows six examples of how Landsat data has been used over the last four decades.) To commemorate the anniversary, NASA and the USGS helped organize and participated in several events on July 23. A press briefing was held over the lunch hour at the Newseum in Washington, DC, where presenta- tions included the results of a My American Landscape contest. Earlier this year NASA and the USGS sent out a press release asking Americans to describe landscape change that had impacted their lives and local areas. Of the many responses received, six were chosen for discussion at the press briefing with the changes depicted in time series or pairs of Landsat images. -
DIRECT DETECTION of the L-DWARF DONOR in WZ SAGITTAE Thomas E
The Astrophysical Journal, 816:4 (6pp), 2016 January 1 doi:10.3847/0004-637X/816/1/4 © 2016. The American Astronomical Society. All rights reserved. DIRECT DETECTION OF THE L-DWARF DONOR IN WZ SAGITTAE Thomas E. Harrison1 Department of Astronomy, New Mexico State University, Box 30001, MSC 4500, Las Cruces, NM 88003-8001, USA Received 2015 September 15; accepted 2015 November 20; published 2015 December 21 ABSTRACT Analysis of a large set of phase-resolved K-band spectra of the cataclysmic variable WZ Sge shows that the secondary star of this system appears to be an L-dwarf. Previous K-band spectra of WZ Sge found that the CO 12 overtone bandheads were in emission. We show that absorption from the CO(2,0) bandhead of the donor star 12 creates a dip in the CO(2,0) emission feature. Measuring the motion of this feature over the orbital period, we −1 construct a radial velocity curve that gives a velocity amplitude of Kabs = 520±35 km s , consistent with the previously published values for this parameter. Key words: brown dwarfs – novae, cataclysmic variables – stars: dwarf novae 1. INTRODUCTION Harrison et al. 2004a) and has a very low accretion rate (Patterson 1998), the donor object has remained elusive. Cataclysmic variables (CVs) are short period binaries where While direct photospheric absorption features from the donor the white dwarf primary is accreting matter from a lower mass in WZ Sge have not previously been detected, Hα emission, secondary star. An angular momentum loss process keeps the ( ) due to the irradiation of the companion during the 2001 system in contact c.f., King & Kolb 1995 , and the orbital outburst, were clearly seen, and led to the first quantitative period shortens over time as the secondary continues to lose constraints on the nature of the secondary. -
The Minor Planet Bulletin
THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 36, NUMBER 3, A.D. 2009 JULY-SEPTEMBER 77. PHOTOMETRIC MEASUREMENTS OF 343 OSTARA Our data can be obtained from http://www.uwec.edu/physics/ AND OTHER ASTEROIDS AT HOBBS OBSERVATORY asteroid/. Lyle Ford, George Stecher, Kayla Lorenzen, and Cole Cook Acknowledgements Department of Physics and Astronomy University of Wisconsin-Eau Claire We thank the Theodore Dunham Fund for Astrophysics, the Eau Claire, WI 54702-4004 National Science Foundation (award number 0519006), the [email protected] University of Wisconsin-Eau Claire Office of Research and Sponsored Programs, and the University of Wisconsin-Eau Claire (Received: 2009 Feb 11) Blugold Fellow and McNair programs for financial support. References We observed 343 Ostara on 2008 October 4 and obtained R and V standard magnitudes. The period was Binzel, R.P. (1987). “A Photoelectric Survey of 130 Asteroids”, found to be significantly greater than the previously Icarus 72, 135-208. reported value of 6.42 hours. Measurements of 2660 Wasserman and (17010) 1999 CQ72 made on 2008 Stecher, G.J., Ford, L.A., and Elbert, J.D. (1999). “Equipping a March 25 are also reported. 0.6 Meter Alt-Azimuth Telescope for Photometry”, IAPPP Comm, 76, 68-74. We made R band and V band photometric measurements of 343 Warner, B.D. (2006). A Practical Guide to Lightcurve Photometry Ostara on 2008 October 4 using the 0.6 m “Air Force” Telescope and Analysis. Springer, New York, NY. located at Hobbs Observatory (MPC code 750) near Fall Creek, Wisconsin. -
A Needs Analysis Study of Amateur Astronomers for the National Virtual Observatory : Aaron Price1 Lou Cohen1 Janet Mattei1 Nahide Craig2
A Needs Analysis Study of Amateur Astronomers For the National Virtual Observatory : Aaron Price1 Lou Cohen1 Janet Mattei1 Nahide Craig2 1Clinton B. Ford Astronomical Data & Research Center American Association of Variable Star Observers 25 Birch St, Cambridge MA 02138 2Space Sciences Laboratory University of California, Berkeley 7 Gauss Way Berkeley, CA 94720-7450 Abstract Through a combination of qualitative and quantitative processes, a survey was con- ducted of the amateur astronomy community to identify outstanding needs which the National Virtual Observatory (NVO) could fulfill. This is the final report of that project, which was conducted by The American Association of Variable Star Observers (AAVSO) on behalf of the SEGway Project at the Center for Science Educations @ Space Sci- ences Laboratory, UC Berkeley. Background The American Association of Variable Star Observers (AAVSO) has worked on behalf of the SEGway Project at the Center for Science Educations @ Space Sciences Labo- ratory, UC Berkeley, to conduct a needs analysis study of the amateur astronomy com- munity. The goal of the study is to identify outstanding needs in the amateur community which the National Virtual Observatory (NVO) project can fulfill. The AAVSO is a non-profit, independent organization dedicated to the study of vari- able stars. It was founded in 1911 and currently has a database of over 11 million vari- able star observations, the vast majority of which were made by amateur astronomers. The AAVSO has a rich history and extensive experience working with amateur astrono- mers and specifically in fostering amateur-professional collaboration. AAVSO Director Dr. Janet Mattei headed the team assembled by the AAVSO. -
The Minor Planet Bulletin and How the Situation Has Gone from One Mt Tarana Observatory of Trying to Fill Pages to One of Fitting Everything In
THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 33, NUMBER 2, A.D. 2006 APRIL-JUNE 29. PHOTOMETRY OF ASTEROIDS 133 CYRENE, adjusted up or down to line up with the V-band data). The near- 454 MATHESIS, 477 ITALIA, AND 2264 SABRINA perfect overlay of V- and R-band data show no evidence of color change as the asteroid rotates. This result replicates the lightcurve Robert K. Buchheim period reported by Harris et al. (1984), and matches the period and Altimira Observatory lightcurve shape reported by Behrend (2005) at his website. 18 Altimira, Coto de Caza, CA 92679 USA [email protected] (Received: 4 November Revised: 21 November) Photometric studies of asteroids 133 Cyrene, 454 Mathesis, 477 Italia and 2264 Sabrina are reported. The lightcurve period for Cyrene of 12.707±0.015 h (with amplitude 0.22 mag) confirms prior studies. The lightcurve period of 8.37784±0.00003 h (amplitude 0.32 mag) for Mathesis differs from previous studies. For Italia, color indices (B-V)=0.87±0.07, (V-R)=0.48±0.05, and phase curve parameters H=10.4, G=0.15 have been determined. For Sabrina, this study provides the first reported lightcurve period 43.41±0.02 h, with 0.30 mag amplitude. Altimira Observatory, located in southern California, is equipped with a 0.28-m Schmidt-Cassegrain telescope (Celestron NexStar- 454 Mathesis. DiMartino et al. (1994) reported a rotation period of 11 operating at F/6.3), and CCD imager (ST-8XE NABG, with 7.075 h with amplitude 0.28 mag for this asteroid, based on two Johnson-Cousins filters). -
Venus Transit 5−6 June 2012 (From 22:00 to 4:56 UT) Australia, Japan, Norway
Venus Transit 5−6 June 2012 (from 22:00 to 4:56 UT) Australia, Japan, Norway Objective The main objective of the venus-2012.org project is the observation of the Venus Transit that will take place on 5th/6th June 2012 (see Fig. 1) from three locations: Australia, Japan and Norway. In particular the project will: 1) Perform live broadcasting of the event (sky-live.tv). 2) Promote educational activities usingFIGURE images 1 obtained during the transit (astroaula.net). Global Visibility of the Transit of Venus of 2012 June 05/06 Region X* Greatest Transit Transit at Zenith Transit Sunset Sunset Begins Ends at at IV I IV I Transit at at Entire Ends No Transit III II III II Sunrise in Progress Begins Transit Sunrise in Progress Transit at Sunset Visible Transit Visible at Sunrise Transit (June 05) (June 06) Region Y* F. Espenak, NASAs GSFC eclipse.gsfc.nasa.gov/OH/transit12.html * Region X - Beginning and end of Transit are visible, but the Sun sets for a short period around maximum transit. * Region Y - Beginning and end of Transit are NOT visible, but the Sun rises for a short period around maximum transit. Figure 1. Earth map showing visibility of the Venus transit in 2012 (credit F. Espenak, NASA/GSFC). The Phenomenon A transit of an astronomical object occurs when it appears to move across the disc of another object which has a larger apparent size. There are different types of transits, like the Galilean moons on Jupiter’s disc, and exoplanets moving across their mother star. -
Flaming Star the Flaming Star Nebula (IC 405) in the Constellation Auriga Is a Surprisingly Colorful and Dramatic Emission/Reflection Nebula
WESTCHESTER AMATEUR ASTRONOMERS January 2016 Image Copyright: Mauri Rosenthal Flaming Star The Flaming Star Nebula (IC 405) in the constellation Auriga is a surprisingly colorful and dramatic emission/reflection nebula. In This Issue . The most prominent star in the image is the variable blue dwarf AE pg. 2 Events For January Aurigae, burning with sufficient intensity to knock electrons off pg. 3 Almanac the hydrogen molecules found in a cloud 5 light years across, pg. 4 Vivian Towers which in turn emit red light. The bluish gray area is not from ion- pg. 5 The Radio Sky ized Oxygen (as found in the Veil Nebula); rather it is mostly a pg. 11 Kepler cloud of carbon dust, which reflects the blue light from the nearby pg. 12 President’s Report star. The result is an emission/reflection nebula 1500 light years distant and accessible from the suburbs with a small telescope. Mauri Rosenthal imaged this from his backyard in Scarsdale with a guided Questar 3.5” telescope over two nights in November using CLS (broadband) and H-alpha (narrowband) filters. Total exposure time was 9.5 hours. SERVING THE ASTRONOMY COMMUNITY SINCE 1986 1 WESTCHESTER AMATEUR ASTRONOMERS January 2016 WAA January Lecture Club Dates 2016 “Light Pollution” Friday January 8th, 7:30pm 2016 Lecture Dates Leinhard Lecture Hall, January 8 June 3 February 5 Sept. 16 Pace University, Pleasantville, NY March 4 October 7 Charles Fulco will speak on light pollution, the Inter- April 1 November 4 national Dark-Sky Association and preserving our May 6 December 2 night sky. -
Variable Star Classification and Light Curves Manual
Variable Star Classification and Light Curves An AAVSO course for the Carolyn Hurless Online Institute for Continuing Education in Astronomy (CHOICE) This is copyrighted material meant only for official enrollees in this online course. Do not share this document with others. Please do not quote from it without prior permission from the AAVSO. Table of Contents Course Description and Requirements for Completion Chapter One- 1. Introduction . What are variable stars? . The first known variable stars 2. Variable Star Names . Constellation names . Greek letters (Bayer letters) . GCVS naming scheme . Other naming conventions . Naming variable star types 3. The Main Types of variability Extrinsic . Eclipsing . Rotating . Microlensing Intrinsic . Pulsating . Eruptive . Cataclysmic . X-Ray 4. The Variability Tree Chapter Two- 1. Rotating Variables . The Sun . BY Dra stars . RS CVn stars . Rotating ellipsoidal variables 2. Eclipsing Variables . EA . EB . EW . EP . Roche Lobes 1 Chapter Three- 1. Pulsating Variables . Classical Cepheids . Type II Cepheids . RV Tau stars . Delta Sct stars . RR Lyr stars . Miras . Semi-regular stars 2. Eruptive Variables . Young Stellar Objects . T Tau stars . FUOrs . EXOrs . UXOrs . UV Cet stars . Gamma Cas stars . S Dor stars . R CrB stars Chapter Four- 1. Cataclysmic Variables . Dwarf Novae . Novae . Recurrent Novae . Magnetic CVs . Symbiotic Variables . Supernovae 2. Other Variables . Gamma-Ray Bursters . Active Galactic Nuclei 2 Course Description and Requirements for Completion This course is an overview of the types of variable stars most commonly observed by AAVSO observers. We discuss the physical processes behind what makes each type variable and how this is demonstrated in their light curves. Variable star names and nomenclature are placed in a historical context to aid in understanding today’s classification scheme. -
The Icha Newsletter Newsletter of the Inter-Union Commission For
International Astronomical Union International Union of the History and Philosophy of Science DHS/IUHPS ______________________________________________________________________________________________________________________ THE ICHA NEWSLETTER NEWSLETTER OF THE INTER-UNION COMMISSION FOR HISTORY OF ASTRONOMY* ____________________________________________________________ __________________________________________________________ No. 12 – November 2011 SUMMARY A. C41/ICHA Programme at the 2012 Beijing IAU General Assembly by C. Ruggles ............................................................................................................ 2 B. 2012-2015 C41 Organizing Committee Elections by C. Ruggles ……...…… 3 C. Journals and Publications: - Acta Historica Astronomiae by H.W. Duerbeck ........................................ 4 Books 2011 …………………………………………………………………. 5 Some research papers by C41/ICHA members – 2011…… ........................... 5 D. News - Formation of Johannes Kepler Working Group by A. E. L. Davis ………. 5 - The Transit of Venus Working Group Activities by H. W. Duerbeck ….. 6 o Solar parallax Conference (Announcement) o Venus Transit Conference (Announcement) o Special Venus Transit issue of JAHH (Announcement) - Sullivan Papers Available by E. N. Bouton ..…………………………… 7 - History of astronomy in India by B. S. Shylaja …………….………….… 8 - 3 rd Conference on Cultural Astronomy by E. Badolati…………..………. 9 - Nexus International Conference on Architecture and Mathematics by G. Magli ……………………………………………………………………. 10 E. ICHA Member -
1 Rotation Periods of Binary Asteroids with Large Separations
Rotation Periods of Binary Asteroids with Large Separations – Confronting the Escaping Ejecta Binaries Model with Observations a,b,* b a D. Polishook , N. Brosch , D. Prialnik a Department of Geophysics and Planetary Sciences, Tel-Aviv University, Israel. b The Wise Observatory and the School of Physics and Astronomy, Tel-Aviv University, Israel. * Corresponding author: David Polishook, [email protected] Abstract Durda et al. (2004), using numerical models, suggested that binary asteroids with large separation, called Escaping Ejecta Binaries (EEBs), can be created by fragments ejected from a disruptive impact event. It is thought that six binary asteroids recently discovered might be EEBs because of the high separation between their components (~100 > a/Rp > ~20). However, the rotation periods of four out of the six objects measured by our group and others and presented here show that these suspected EEBs have fast rotation rates of 2.5 to 4 hours. Because of the small size of the components of these binary asteroids, linked with this fast spinning, we conclude that the rotational-fission mechanism, which is a result of the thermal YORP effect, is the most likely formation scenario. Moreover, scaling the YORP effect for these objects shows that its timescale is shorter than the estimated ages of the three relevant Hirayama families hosting these binary asteroids. Therefore, only the largest (D~19 km) suspected asteroid, (317) Roxane , could be, in fact, the only known EEB. In addition, our results confirm the triple nature of (3749) Balam by measuring mutual events on its lightcurve that match the orbital period of a nearby satellite in addition to its distant companion.