Chiron and the Centaurs: Escapees from the Kuiper Belt
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Surface Characteristics of Transneptunian Objects and Centaurs from Photometry and Spectroscopy
Barucci et al.: Surface Characteristics of TNOs and Centaurs 647 Surface Characteristics of Transneptunian Objects and Centaurs from Photometry and Spectroscopy M. A. Barucci and A. Doressoundiram Observatoire de Paris D. P. Cruikshank NASA Ames Research Center The external region of the solar system contains a vast population of small icy bodies, be- lieved to be remnants from the accretion of the planets. The transneptunian objects (TNOs) and Centaurs (located between Jupiter and Neptune) are probably made of the most primitive and thermally unprocessed materials of the known solar system. Although the study of these objects has rapidly evolved in the past few years, especially from dynamical and theoretical points of view, studies of the physical and chemical properties of the TNO population are still limited by the faintness of these objects. The basic properties of these objects, including infor- mation on their dimensions and rotation periods, are presented, with emphasis on their diver- sity and the possible characteristics of their surfaces. 1. INTRODUCTION cally with even the largest telescopes. The physical char- acteristics of Centaurs and TNOs are still in a rather early Transneptunian objects (TNOs), also known as Kuiper stage of investigation. Advances in instrumentation on tele- belt objects (KBOs) and Edgeworth-Kuiper belt objects scopes of 6- to 10-m aperture have enabled spectroscopic (EKBOs), are presumed to be remnants of the solar nebula studies of an increasing number of these objects, and signifi- that have survived over the age of the solar system. The cant progress is slowly being made. connection of the short-period comets (P < 200 yr) of low We describe here photometric and spectroscopic studies orbital inclination and the transneptunian population of pri- of TNOs and the emerging results. -
KAREN J. MEECH February 7, 2019 Astronomer
BIOGRAPHICAL SKETCH – KAREN J. MEECH February 7, 2019 Astronomer Institute for Astronomy Tel: 1-808-956-6828 2680 Woodlawn Drive Fax: 1-808-956-4532 Honolulu, HI 96822-1839 [email protected] PROFESSIONAL PREPARATION Rice University Space Physics B.A. 1981 Massachusetts Institute of Tech. Planetary Astronomy Ph.D. 1987 APPOINTMENTS 2018 – present Graduate Chair 2000 – present Astronomer, Institute for Astronomy, University of Hawaii 1992-2000 Associate Astronomer, Institute for Astronomy, University of Hawaii 1987-1992 Assistant Astronomer, Institute for Astronomy, University of Hawaii 1982-1987 Graduate Research & Teaching Assistant, Massachusetts Inst. Tech. 1981-1982 Research Specialist, AAVSO and Massachusetts Institute of Technology AWARDS 2018 ARCs Scientist of the Year 2015 University of Hawai’i Regent’s Medal for Research Excellence 2013 Director’s Research Excellence Award 2011 NASA Group Achievement Award for the EPOXI Project Team 2011 NASA Group Achievement Award for EPOXI & Stardust-NExT Missions 2009 William Tylor Olcott Distinguished Service Award of the American Association of Variable Star Observers 2006-8 National Academy of Science/Kavli Foundation Fellow 2005 NASA Group Achievement Award for the Stardust Flight Team 1996 Asteroid 4367 named Meech 1994 American Astronomical Society / DPS Harold C. Urey Prize 1988 Annie Jump Cannon Award 1981 Heaps Physics Prize RESEARCH FIELD AND ACTIVITIES • Developed a Discovery mission concept to explore the origin of Earth’s water. • Co-Investigator on the Deep Impact, Stardust-NeXT and EPOXI missions, leading the Earth-based observing campaigns for all three. • Leads the UH Astrobiology Research interdisciplinary program, overseeing ~30 postdocs and coordinating the research with ~20 local faculty and international partners. -
Triton: Topography and Geology of a Probable Ocean World with Comparison to Pluto and Charon
remote sensing Article Triton: Topography and Geology of a Probable Ocean World with Comparison to Pluto and Charon Paul M. Schenk 1,* , Chloe B. Beddingfield 2,3, Tanguy Bertrand 3, Carver Bierson 4 , Ross Beyer 2,3, Veronica J. Bray 5, Dale Cruikshank 3 , William M. Grundy 6, Candice Hansen 7, Jason Hofgartner 8 , Emily Martin 9, William B. McKinnon 10, Jeffrey M. Moore 3, Stuart Robbins 11 , Kirby D. Runyon 12 , Kelsi N. Singer 11 , John Spencer 11, S. Alan Stern 11 and Ted Stryk 13 1 Lunar and Planetary Institute, Houston, TX 77058, USA 2 SETI Institute, Palo Alto, CA 94020, USA; chloe.b.beddingfi[email protected] (C.B.B.); [email protected] (R.B.) 3 NASA Ames Research Center, Moffett Field, CA 94035, USA; [email protected] (T.B.); [email protected] (D.C.); [email protected] (J.M.M.) 4 School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85202, USA; [email protected] 5 Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85641, USA; [email protected] 6 Lowell Observatory, Flagstaff, AZ 86001, USA; [email protected] 7 Planetary Science Institute, Tucson, AZ 85704, USA; [email protected] 8 Jet Propulsion Laboratory, Pasadena, CA 91001, USA; [email protected] 9 National Air & Space Museum, Washington, DC 20001, USA; [email protected] 10 Department of Earth and Planetary Sciences, Washington University in Saint Louis, Saint Louis, MO 63101, USA; [email protected] 11 Southwest Research Institute, Boulder, CO 80301, USA; [email protected] (S.R.); [email protected] (K.N.S.); [email protected] (J.S.); [email protected] (S.A.S.) Citation: Schenk, P.M.; Beddingfield, 12 Johns Hopkins Applied Physics Laboratory, Laurel, MD 20707, USA; [email protected] 13 C.B.; Bertrand, T.; Bierson, C.; Beyer, Humanities Division, Roane State Community College, Harriman, TN 37748, USA; [email protected] R.; Bray, V.J.; Cruikshank, D.; Grundy, * Correspondence: [email protected] W.M.; Hansen, C.; Hofgartner, J.; et al. -
Comet Section Observing Guide
Comet Section Observing Guide 1 The British Astronomical Association Comet Section www.britastro.org/comet BAA Comet Section Observing Guide Front cover image: C/1995 O1 (Hale-Bopp) by Geoffrey Johnstone on 1997 April 10. Back cover image: C/2011 W3 (Lovejoy) by Lester Barnes on 2011 December 23. © The British Astronomical Association 2018 2018 December (rev 4) 2 CONTENTS 1 Foreword .................................................................................................................................. 6 2 An introduction to comets ......................................................................................................... 7 2.1 Anatomy and origins ............................................................................................................................ 7 2.2 Naming .............................................................................................................................................. 12 2.3 Comet orbits ...................................................................................................................................... 13 2.4 Orbit evolution .................................................................................................................................... 15 2.5 Magnitudes ........................................................................................................................................ 18 3 Basic visual observation ........................................................................................................ -
Charon Tectonics
Icarus 287 (2017) 161–174 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Charon tectonics ∗ Ross A. Beyer a,b, , Francis Nimmo c, William B. McKinnon d, Jeffrey M. Moore b, Richard P. Binzel e, Jack W. Conrad c, Andy Cheng f, K. Ennico b, Tod R. Lauer g, C.B. Olkin h, Stuart Robbins h, Paul Schenk i, Kelsi Singer h, John R. Spencer h, S. Alan Stern h, H.A. Weaver f, L.A. Young h, Amanda M. Zangari h a Sagan Center at the SETI Institute, 189 Berndardo Ave, Mountain View, California 94043, USA b NASA Ames Research Center, Moffet Field, CA 94035-0 0 01, USA c University of California, Santa Cruz, CA 95064, USA d Washington University in St. Louis, St Louis, MO 63130-4899, USA e Massachusetts Institute of Technology, Cambridge, MA 02139, USA f Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA g National Optical Astronomy Observatories, Tucson, AZ 85719, USA h Southwest Research Institute, Boulder, CO 80302, USA i Lunar and Planetary Institute, Houston, TX 77058, USA a r t i c l e i n f o a b s t r a c t Article history: New Horizons images of Pluto’s companion Charon show a variety of terrains that display extensional Received 14 April 2016 tectonic features, with relief surprising for this relatively small world. These features suggest a global ex- Revised 8 December 2016 tensional areal strain of order 1% early in Charon’s history. Such extension is consistent with the presence Accepted 12 December 2016 of an ancient global ocean, now frozen. -
A Search for Temporal Changes on Pluto and Charon
A Search for Temporal Changes on Pluto and Charon J. D. Hofgartner*1, B. J. Buratti1, S. L. Devins1, R. A. Beyer2,3, P. Schenk4, S. A. Stern5, H. A. Weaver6, C. B. Olkin5, A. Cheng6, K. Ennico3, T. R. Lauer7, W. B. McKinnon8, J. Spencer5, L. A. Young5, and the New Horizons Science Team *Corresponding author ([email protected]); 1. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA; 2. Sagan Center at the SETI Institute, Mountain View, CA; 3. NASA Ames Research Center, Moffett Field, CA; 4. Lunar and Planetary Institute, Houston, TX; 5. Southwest Research Institute, Boulder, CO; 6. Johns Hopkins University Applied Physics Laboratory, Laurel, MD; 7. National Optical Astronomy Observatory, Tucson, AZ; 8. Washington University in St. Louis, Saint Louis, MO; Abstract: A search for temporal changes on Pluto and Charon was motivated by (1) the discovery of young surfaces in the Pluto system that imply ongoing or recent geologic activity, (2) the detection of active plumes on Triton during the Voyager 2 flyby, and (3) the abundant and detailed information that observing geologic processes in action provides about the processes. A thorough search for temporal changes using New Horizons images was completed. Images that covered the same region were blinked and manually inspected for any differences in appearance. The search included full-disk images such that all illuminated regions of both bodies were investigated and higher resolution images such that parts of the encounter hemispheres were investigated at finer spatial scales. Changes of appearance between different images were observed but in all cases were attributed to variability of the imaging parameters (especially geometry) or artifacts. -
Molecular Reconnaissance of the $\Beta $ Pictoris Gas Disk with The
Draft version January 15, 2018 Typeset using LATEX twocolumn style in AASTeX61 MOLECULAR RECONNAISSANCE OF THE β PICTORIS GAS DISK WITH THE SMA: A LOW HCN/(CO+CO2) OUTGASSING RATIO AND PREDICTIONS FOR FUTURE SURVEYS L. Matra`,1, ∗ D. J. Wilner,1 K. I. Oberg,¨ 1 S. M. Andrews,1 R. A. Loomis,1 M. C. Wyatt,2 and W. R. F. Dent3 1Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 2Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK 3ALMA Santiago Central Offices, Alonso de Cordova 3107, Vitacura, Santiago, Chile (Received 2017 September 13; Revised 2017 December 20; Accepted 2017 December 24) ABSTRACT The exocometary origin of CO gas has been confirmed in several extrasolar Kuiper belts, with CO ice abundances consistent with Solar System comets. We here present a molecular survey of the β Pictoris belt with the Submillimeter + + Array (SMA), reporting upper limits for CN, HCN, HCO ,N2H and H2CO, as well as for H2S, CH3OH, SiO and DCN from archival ALMA data. Non-detections can be attributed to rapid molecular photodissociation due to the A- star's strong UV flux. CN is the longest-lasting and most easily detectable molecule after CO in this environment. We update our NLTE excitation model to include UV fluorescence, finding it plays a key role in CO and CN excitation, and use it to turn the SMA CN/CO flux ratio constraint into an upper limit of < 2:5% on the HCN/(CO+CO2) ratio of outgassing rates. This value is consistent with, but at the low end of, the broad range observed in Solar System comets. -
Water Ice in 2060 Chiron and Its Implications for Centaurs and Kuiper Belt Objects
Water Ice in 2060 Chiron and its Implications for Centaurs and Kuiper Belt Objects Jane X. Luu Sterrewacht Leiden Postbus 9513, 2300RA Leiden, The Netherlands David C. Jewitt1 Institute for Astronomy 2680 Woodlawn Drive, Honolulu, HI 96822 and Chad Trujillo1 Institute for Astronomy 2680 Woodlawn Drive, Honolulu, HI 96822 Received ; accepted Submitted to Ap. J. Letters, accepted 31 Jan 2000 1Visiting Astronomer, W. M. Keck Observatory, jointly operated by California Institute of Technology and the University of California. –2– ABSTRACT We report the detection of water ice in the Centaur 2060 Chiron, based on near-infrared spectra (1.0 - 2.5 µm) taken with the 3.8-meter United Kingdom Infrared Telescope (UKIRT) and the 10-meter Keck Telescope. The appearance of this ice is correlated with the recent decline in Chiron’s cometary activity: the decrease in the coma cross-section allows previously hidden solid-state surface features to be seen. We predict that water ice is ubiquitous among Centaurs and Kuiper Belt objects, but its surface coverage varies from object to object, and thus determines its detectability and the occurrence of cometary activity. Subject headings: comets – Kuiper Belt – solar system: formation 1. Introduction The Centaurs are a set of solar system objects whose orbits are confined between those of Jupiter and Neptune. Their planet-crossing orbits imply a short dynamical lifetime (106 107 yr). The current belief is that Centaurs are objects scattered from the Kuiper − Belt that may eventually end up in the inner solar system as short-period comets. The first discovered and brightest known Centaur, 2060 Chiron, is relatively well studied. -
VITA David Jewitt Address Dept. Earth, Planetary and Space
VITA David Jewitt Address Dept. Earth, Planetary and Space Sciences, UCLA 595 Charles Young Drive East, Box 951567 Los Angeles, CA 90095-1567 [email protected], http://www2.ess.ucla.edu/~jewitt/ Education B. Sc. University College London 1979 M. S. California Institute of Technology 1980 Ph. D. California Institute of Technology 1983 Professional Experience Summer Student Royal Greenwich Observatory 1978 Anthony Fellowship California Institute of Technology 1979-1980 Research Assistant California Institute of Technology 1980-1983 Assistant Professor Massachusetts Institute of Technology 1983-1988 Associate Professor and Astronomer University of Hawaii 1988-1993 Professor and Astronomer University of Hawaii 1993-2009 Professor Dept. Earth, Planetary & Space Sciences, UCLA 2009- Inst. of Geophys & Planetary Physics, UCLA 2009-2011 Dept. Physics & Astronomy, UCLA 2010- Director Institute for Planets & Exoplanets, UCLA, 2011- Honors Regent's Medal, University of Hawaii 1994 Scientist of the Year, ARCS 1996 Exceptional Scientific Achievement Award, NASA 1996 Fellow of University College London 1998 Fellow of the American Academy of Arts and Sciences 2005 Fellow of the American Association for the Advancement of Science 2005 Member of the National Academy of Sciences 2005 National Observatory, Chinese Academy of Sciences, Honorary Professor 2006-2011 National Central University, Taiwan, Adjunct Professor 2007 The Shaw Prize for Astronomy 2012 The Kavli Prize for Astrophysics 2012 Foreign Member, Norwegian Academy of Sciences & Letters 2012 Research -
Isotopic Ratios in Outbursting Comet C/2015 ER61
Astronomy & Astrophysics manuscript no. draft_Dec_07 c ESO 2018 September 10, 2018 Isotopic ratios in outbursting comet C/2015 ER61 Bin Yang1; 2, Damien Hutsemékers3, Yoshiharu Shinnaka4, Cyrielle Opitom1, Jean Manfroid3, Emmanuël Jehin3, Karen J. Meech5, Olivier R. Hainaut1, Jacqueline V. Keane5, and Michaël Gillon3 (Affiliations can be found after the references) September 10, 2018 ABSTRACT Isotopic ratios in comets are critical to understanding the origin of cometary material and the physical and chemical conditions in the early solar nebula. Comet C/2015 ER61 (PANSTARRS) underwent an outburst with a total brightness increase of 2 magnitudes on the night of 2017 April 4. The sharp increase in brightness offered a rare opportunity to measure the isotopic ratios of the light elements in the coma of this comet. We obtained two high-resolution spectra of C/2015 ER61 with UVES/VLT on the nights of 2017 April 13 and 17. At the time of our observations, the comet was fading gradually following the outburst. We measured the nitrogen and carbon isotopic ratios from the CN violet (0,0) band and found that 12C/13C=100 ± 15, 14N/15N=130 ± 15. 14 15 14 15 In addition, we determined the N/ N ratio from four pairs of NH2 isotopolog lines and measured N/ N=140 ± 28. The measured isotopic ratios of C/2015 ER61 do not deviate significantly from those of other comets. Key words. comets: general - comets: individual (C/2015 ER61) - methods: observational 1. Introduction Understanding how planetary systems form from proto- planetary disks remains one of the great challenges in as- tronomy. -
Project Pan-STARRS and the Outer Solar System
Project Pan-STARRS and the Outer Solar System David Jewitt Institute for Astronomy, 2680 Woodlawn Drive, Honolulu, HI 96822 ABSTRACT Pan-STARRS, a funded project to repeatedly survey the entire visible sky to faint limiting magnitudes (mR ∼ 24), will have a substantial impact on the study of the Kuiper Belt and outer solar system. We briefly review the Pan- STARRS design philosophy and sketch some of the planetary science areas in which we expect this facility to make its mark. Pan-STARRS will find ∼20,000 Kuiper Belt Objects within the first year of operation and will obtain accurate astrometry for all of them on a weekly or faster cycle. We expect that it will revolutionise our knowledge of the contents and dynamical structure of the outer solar system. Subject headings: Surveys, Kuiper Belt, comets 1. Introduction to Pan-STARRS Project Pan-STARRS (short for Panoramic Survey Telescope and Rapid Response Sys- tem) is a collaboration between the University of Hawaii's Institute for Astronomy, the MIT Lincoln Laboratory, the Maui High Performance Computer Center, and Science Ap- plications International Corporation. The Principal Investigator for the project, for which funding started in the fall of 2002, is Nick Kaiser of the Institute for Astronomy. Operations should begin by 2007. The science objectives of Pan-STARRS span the full range from planetary to cosmolog- ical. The instrument will conduct a survey of the solar system that is staggering in power compared to anything yet attempted. A useful measure of the raw survey power, SP , of a telescope is given by AΩ SP = (1) θ2 where A [m2] is the collecting area of the telescope primary, Ω [deg2] is the solid angle that is imaged and θ [arcsec] is the full-width at half maximum (FWHM) of the images { 2 { produced by the telescope. -
PHYSICAL MECHANISM of COMET (AND ASTEROID) OUTBURSTS: the MOVIE William K
78th Annual Meeting of the Meteoritical Society (2015) 5002.pdf PHYSICAL MECHANISM OF COMET (AND ASTEROID) OUTBURSTS: THE MOVIE William K. Hartman, Planetary Science Institute, 1700 E. Ft. Lowell Road, Tucson, AZ 85719 The asteroid-comet continuum has been observationally demonstrated since spectrometric work in the early 1980s [1,2]. Here I describe a mechanism explaining sporadic comet (and “as- teroid”) outbursts, illustrated by experiments conducted in 1976 at the NASA Ames Research Center=s Vertical Gun Facility (VGF). I studied low velocity impacts into simulated regolith powders and gravels, in order to examine physics of low-velocity collisions during early solar system planetesimal formation. In one Aaccidental@ experiment, the bucket of powder remained gas- charged during evacuation of the VGF vacuum chamber. The impactor, moving at 5.5 m/s, disturbed the surface, initiating an explosive eruption of the dust-charged gas, shooting in jets from multiple vents near the impact site at speeds up to about 3 m/s, with sporadic venting until 17 seconds after the impact. This experiment was described in [3], which concluded that it simulated comet eruption phenomena. In this hypothesis, a com- et nucleus develops a lag deposit of regolith, and as the body reaches a certain distance from the sun, the thermal wave pene- trates to an ice-rich depth, causing sublimation. Gas rises into the regolith pore spaces, and creates a gas-charged powder, as in our experiment. Any disturbance of the surface, such as a mete- oroid, initiates a temporary jet. In the absence of such a disturb- ance, the gas pressure becomes sufficient to blow off the over- burden and initiate widespread eruptions, as seen in Giotto imag- es of P/Halley.