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Radio and IR Interferometry of Sio Maser Stars
Cosmic Masers - from OH to H0 Proceedings IAU Symposium No. 287, 2012 c International Astronomical Union 2012 R.S. Booth, E.M.L. Humphreys & W.H.T. Vlemmings, eds. doi:10.1017/S1743921312006989 Radio and IR interferometry of SiO maser stars Markus Wittkowski1, David A. Boboltz2,MalcolmD.Gray3, Elizabeth M. L. Humphreys1 Iva Karovicova4, and Michael Scholz5,6 1 ESO, Karl-Schwarzschild-Str. 2, 85748 Garching bei M¨unchen, Germany 2 US Naval Observatory, 3450 Massachusetts Avenue, NW, Washington, DC 20392-5420, USA 3 Jodrell Bank Centre for Astrophysics, Alan Turing Building, University of Manchester, Manchester M13 9PL, UK 4 Max-Planck-Institut f¨ur Astronomie, K¨onigstuhl 17, 69117 Heidelberg, Germany 5 Zentrum f¨ur Astronomie der Universit¨at Heidelberg (ZAH), Institut f¨ur Theoretische Astrophysik, Albert-Ueberle-Str. 2, 69120 Heidelberg, Germany 6 Sydney Institute for Astronomy, School of Physics, University of Sydney, Sydney NSW 2006, Australia Abstract. Radio and infrared interferometry of SiO maser stars provide complementary infor- mation on the atmosphere and circumstellar environment at comparable spatial resolution. Here, we present the latest results on the atmospheric structure and the dust condensation region of AGB stars based on our recent infrared spectro-interferometric observations, which represent the environment of SiO masers. We discuss, as an example, new results from simultaneous VLTI and VLBA observations of the Mira variable AGB star R Cnc, including VLTI near- and mid- infrared interferometry, as well as VLBA observations of the SiO maser emission toward this source. We present preliminary results from a monitoring campaign of high-frequency SiO maser emission toward evolved stars obtained with the APEX telescope, which also serves as a pre- cursor of ALMA images of the SiO emitting region. -
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. -
Evidence for Very Extended Gaseous Layers Around O-Rich Mira Variables and M Giants B
The Astrophysical Journal, 579:446–454, 2002 November 1 # 2002. The American Astronomical Society. All rights reserved. Printed in U.S.A. EVIDENCE FOR VERY EXTENDED GASEOUS LAYERS AROUND O-RICH MIRA VARIABLES AND M GIANTS B. Mennesson,1 G. Perrin,2 G. Chagnon,2 V. Coude du Foresto,2 S. Ridgway,3 A. Merand,2 P. Salome,2 P. Borde,2 W. Cotton,4 S. Morel,5 P. Kervella,5 W. Traub,6 and M. Lacasse6 Received 2002 March 15; accepted 2002 July 3 ABSTRACT Nine bright O-rich Mira stars and five semiregular variable cool M giants have been observed with the Infrared and Optical Telescope Array (IOTA) interferometer in both K0 (2.15 lm) and L0 (3.8 lm) broad- band filters, in most cases at very close variability phases. All of the sample Mira stars and four of the semire- gular M giants show strong increases, from ’20% to ’100%, in measured uniform-disk (UD) diameters between the K0 and L0 bands. (A selection of hotter M stars does not show such a large increase.) There is no evidence that K0 and L0 broadband visibility measurements should be dominated by strong molecular bands, and cool expanding dust shells already detected around some of these objects are also found to be poor candi- dates for producing these large apparent diameter increases. Therefore, we propose that this must be a con- tinuum or pseudocontinuum opacity effect. Such an apparent enlargement can be reproduced using a simple two-component model consisting of a warm (1500–2000 K), extended (up to ’3 stellar radii), optically thin ( ’ 0:5) layer located above the classical photosphere. -
Where Are the Distant Worlds? Star Maps
W here Are the Distant Worlds? Star Maps Abo ut the Activity Whe re are the distant worlds in the night sky? Use a star map to find constellations and to identify stars with extrasolar planets. (Northern Hemisphere only, naked eye) Topics Covered • How to find Constellations • Where we have found planets around other stars Participants Adults, teens, families with children 8 years and up If a school/youth group, 10 years and older 1 to 4 participants per map Materials Needed Location and Timing • Current month's Star Map for the Use this activity at a star party on a public (included) dark, clear night. Timing depends only • At least one set Planetary on how long you want to observe. Postcards with Key (included) • A small (red) flashlight • (Optional) Print list of Visible Stars with Planets (included) Included in This Packet Page Detailed Activity Description 2 Helpful Hints 4 Background Information 5 Planetary Postcards 7 Key Planetary Postcards 9 Star Maps 20 Visible Stars With Planets 33 © 2008 Astronomical Society of the Pacific www.astrosociety.org Copies for educational purposes are permitted. Additional astronomy activities can be found here: http://nightsky.jpl.nasa.gov Detailed Activity Description Leader’s Role Participants’ Roles (Anticipated) Introduction: To Ask: Who has heard that scientists have found planets around stars other than our own Sun? How many of these stars might you think have been found? Anyone ever see a star that has planets around it? (our own Sun, some may know of other stars) We can’t see the planets around other stars, but we can see the 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. -
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. -
Standard Candles in Cosmology
Standard Candles: Distance Measurement in Astronomy Farley V. Ferrante Southern Methodist University 5/3/2017 PHYS 3368: Principles of Astrophysics & Cosmology 1 OUTLINE • Cosmic Distance Ladder • Standard Candles Parallax Cepheid variables Planetary nebula Most luminous supergiants Most luminous globular clusters Most luminous H II regions Supernovae Hubble constant & red shift • Standard Model of Cosmology 5/3/2017 PHYS 3368: Principles of Astrophysics & Cosmology 2 The Cosmic Distance Ladder - Distances far too vast to be measured directly - Several methods of indirect measurement - Clever methods relying on careful observation and basic mathematics - Cosmic distance ladder: A progression of indirect methods which scale, overlap, & calibrate parameters for large distances in terms of smaller distances • More methods calibrate these distances until distances that can be measured directly are achieved 5/3/2017 PHYS 3368: Principles of Astrophysics & Cosmology 3 Standard Candles • Magnitude: Historical unit (Hipparchus) of stellar brightness such that 5 magnitudes represents a factor of 100 in intensity • Apparent magnitude: Number assigned to visual brightness of an object; originally a scale of 1-6 • Absolute magnitude: Magnitude an object would have at 10 pc (convenient distance for comparison) • List of most luminous stars 5/3/2017 PHYS 3368: Principles of Astrophysics & Cosmology 4 5/3/2017 PHYS 3368: Principles of Astrophysics & Cosmology 5 The Cosmic Distance Ladder 5/3/2017 PHYS 3368: Principles of Astrophysics & Cosmology 6 The -
GW Librae: a Unique Laboratory for Pulsations in an Accreting White Dwarf
MNRAS 000,1–11 (2016) Preprint 11 April 2016 Compiled using MNRAS LATEX style file v3.0 GW Librae: A unique laboratory for pulsations in an accreting white dwarf O. Toloza,1? B. T. G¨ansicke,1 J. J. Hermes,2;19 D. M. Townsley,3 M. R. Schreiber4, P. Szkody5, A. Pala1, K. Beuermann6, L. Bildsten7, E. Breedt1, M. Cook8;10, P. Godon9, A. A. Henden10, I. Hubeny11, C. Knigge12, K. S. Long13, T. R. Marsh1, D. de Martino14, A. S. Mukadam5;15, G. Myers10, P. Nelson 16, A. Oksanen9;17, J. Patterson18, E. M. Sion9, M. Zorotovic4 1Department of Physics, University of Warwick, Coventry - CV4 7AL, UK 2Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC 27599-3255, USA 3Department of Physics and Astronomy, The University of Alabama, Tuscaloosa, AL - 35487, USA 4Instituto de F½sica y Astronom½a, Universidad de Valpara½so, Valpara½so, 2360102, Chile 5Department of Astronomy, University of Washington, Seattle, WA - 98195-1580, USA 6Institut f¨urAstrophysik Friedrich-Hund-Platz 1, Georg-August-Universit¨at,G¨ottingen,37077, Germany 7Kavli Institute for Theoretical Physics and Department of Physics Kohn Hall, University of California, Santa Barbara, CA 93106, USA 8Newcastle Observatory, Newcastle, ON L1B 1M5 Canada 9Astrophysics and Planetary Science, Villanova University, Villanova, PA 19085, USA 10American Association Of Variable Star Observers 11Steward Observatory and Dept. of Astronomy, University of Arizona, Tucson, AZ 85721, USA 12School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ, UK 13Space Telescope Science Institute, Baltimore, MD 21218, USA 14Osservatorio Astronomico di Capodimonte, salita Moiariello 16, 80131 Napoli, Italy 15Apache Point Observatory, 2001 Apache Point Road, Sunspot, NM 88349-0059, USA 161105 Hazeldean Rd, Ellinbank 3820, Australia 17Caisey Harlingten Observatory, San Pedro de Atacama, Chile 18Department of Astronomy, Columbia University, New York, NY 10027, USA 19Hubble Fellow Accepted XXX. -
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. -
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. -
10. Scientific Programme 10.1
10. SCIENTIFIC PROGRAMME 10.1. OVERVIEW (a) Invited Discourses Plenary Hall B 18:00-19:30 ID1 “The Zoo of Galaxies” Karen Masters, University of Portsmouth, UK Monday, 20 August ID2 “Supernovae, the Accelerating Cosmos, and Dark Energy” Brian Schmidt, ANU, Australia Wednesday, 22 August ID3 “The Herschel View of Star Formation” Philippe André, CEA Saclay, France Wednesday, 29 August ID4 “Past, Present and Future of Chinese Astronomy” Cheng Fang, Nanjing University, China Nanjing Thursday, 30 August (b) Plenary Symposium Review Talks Plenary Hall B (B) 8:30-10:00 Or Rooms 309A+B (3) IAUS 288 Astrophysics from Antarctica John Storey (3) Mon. 20 IAUS 289 The Cosmic Distance Scale: Past, Present and Future Wendy Freedman (3) Mon. 27 IAUS 290 Probing General Relativity using Accreting Black Holes Andy Fabian (B) Wed. 22 IAUS 291 Pulsars are Cool – seriously Scott Ransom (3) Thu. 23 Magnetars: neutron stars with magnetic storms Nanda Rea (3) Thu. 23 Probing Gravitation with Pulsars Michael Kremer (3) Thu. 23 IAUS 292 From Gas to Stars over Cosmic Time Mordacai-Mark Mac Low (B) Tue. 21 IAUS 293 The Kepler Mission: NASA’s ExoEarth Census Natalie Batalha (3) Tue. 28 IAUS 294 The Origin and Evolution of Cosmic Magnetism Bryan Gaensler (B) Wed. 29 IAUS 295 Black Holes in Galaxies John Kormendy (B) Thu. 30 (c) Symposia - Week 1 IAUS 288 Astrophysics from Antartica IAUS 290 Accretion on all scales IAUS 291 Neutron Stars and Pulsars IAUS 292 Molecular gas, Dust, and Star Formation in Galaxies (d) Symposia –Week 2 IAUS 289 Advancing the Physics of Cosmic -
Asteroids, Comets, Meteors 1991, Pp. 641-643 Lunar and Planetary Institute, Houston, 1992 W/Eg- 641
Asteroids, Comets, Meteors 1991, pp. 641-643 Lunar and Planetary Institute, Houston, 1992 w/eg- 641 THE MASS OF (1) CERES FROM PERTURBATIONS ON (348) MAY Gareth V. Williams Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138, U.S.A. ABSTRACT The most promising ground-based technique for determining the mass of s minor planet is the observation of the perturbations it induces in the motion of another minor planet. This method requires cv.reful observation of both minor planets over extended periods of time. The mass of (1) Ceres has been determined from the perturbations on (348) May, which made three close approaches to Ceres at intervals of 46 years between 1891 and 1984. The motion of May is clearly influenced by Ceres, and by Using different test masses for Ceres, a search has been made to determine the mass of Ceres that minimizes the residuals in the observations of May. Introduction The masses of the largest minor planets are rather poorly known. Traditionally, the masses of the major planets were obtained by observing their mutual perturbations or by observing their satellite systems. These methods are not easily applicable to minor planets: no minor planets are known to have satellites; the minor-planet perturbations on any of the major planets are negligible (from a ground-based viewpoint, except by tracking spacecraft); and the mutual minor-planet perturbations generally are small. However, the mutual-perturbation method, when applied to suitable objects, is the best ground-based method currently available for determimng minor-planet masses. The best circumstances for using this method occur when one of the minor planets is large compared to the other, when the two objects make close, periodic approaches to each other, and when both have long observational histories.