Asteroids, , Meteors (2012) sess151.pdf

Wednesday, May 16, 2012 INTERNAL STRUCTURE OF SMALL BODIES, INCLUDING PRESENCE/FORMATION OF SATELLITES II 2:00 p.m. Snow Hall

Chairs: Jean-Luc Margot Franck Marchis

2:00 p.m. Scheirich P. * Pravec P. Mottola S. Mommert M. Hornoch K. Kušnirák P. Pittichová J. Jacobson S. A. Pray D. Polishook D. Krugly Yu. N. Slyusarev I. Pollock J. Jehin E. Manfroid J. Gillon M. Galád A. Licandro J. Alí-Lagoa V. Brinsfield J. Inasaridze R. Ya. Molotov I. E. Zero Drift in Mean Anomaly of the Satellite of 1996 FG3 and its Implication for the BYORP Theory [#6123] An analysis of photometric observations of binary Near- (175706) 1996 FG3, taken from 1996 to 2012, gave a single solution for a quadratic drift of the mean anomaly of the satellite, 0.0 deg/yr2, consistent with recent BYORP theory.

2:10 p.m. Jacobson S. A. * Scheeres D. J. Forming the Observed Population [#6092] Rotational fission results in the formation of all classes of observed near-Earth asteroid (NEA) binaries. Evolution into each class is the result of mutual body tides, the YORP effect, the binary YORP effect, and planetary flybys.

2:20 p.m. Hergenrother C. W. Kwiatkowski T. * Kryszczyńska A. Prętka-Ziomek H. Polińska M. Gulbis A. Balona L. Buckley D. Crause L. Crawford S. Hettlage Ch. Husser T-O. Kniazev A. Kotze P. Loaring N. O’Donoghue D. Pickering T. Romero Colmenero E. Vaisanen P. New Results on Rotation of Very Small Near-Earth [#6484] We obtained periods of nine very small, fast rotating NEAs. Periods of two of them are close to the maximum spin limit, and were used to determine the tensile strength coefficient. We will also constrain the spin axis of another asteroid.

2:30 p.m. Hirababayashi M. * Scheeres D. J. Fission and Surface Disruption Limits for Rapidly Rotating Asteroids: The Case of Kleopatra [#6158] Asteroids may fail by two different ways: by surface particles lofting off due to centripetal accelerations or through spin fission. We show the fission and surface disruption limit for these failure modes for non-spherical, real asteroid shapes.

2:40 p.m. Marchis F. * Vachier F. Durech J. Berthier J. Wong M. H. Kalas P. Duchene G. van Dam M. Physical Characteristics of the Binary Asteroid (624) Hektor [#6416] We will present the physical properties of the Trojan Binary Asteroid, 624 Hektor, obtained from the analysis of its satellite orbit combined with an estimate of the size and shape of the primary.

2:50 p.m. Colas F. * Berthier J. Vachier F. Degenhardt S. Dunham D. Garlitz J. Georges T. Maley P. Preston S. Timerson B. Venable V. Allain M. Burns K. Cawthon C. Cooper J. R. Enriquez J. E. Fixelle J. Hicks S. Jenniskens P. Marchis F. Meldman-Floch W. L. Merline W. J. Minteer J. Owen W. Philipps M. Shape and Size of (90) ANTIOPE Derived from an Exceptional Stellar on July 19, 2011 [#6427] On 2011 July 19th, an exceptional occultation by (90) ANTIOPE stellar occured over north America. For the first time an accurate silhouette of a double asteroid was used to derive mass and bulk density. A puzzling huge excavation is confirmed.

Asteroids, Comets, Meteors (2012) sess151.pdf

3:00 p.m. Fuse T. * Kuroda D. Asteroidal Satellites Search using Subaru Telescope’s AO Systems [#6489] We conducted a search project of satellites around asteroids using Subaru Telescope’s Adaptive Optics (AO) systems. Two different instrumental combination were used in 2006 and 2009.

3:10 p.m. Arai T. * Kasuga T. Ohtsuka K. Evidence for Incipient Partial Melting of Active Asteroid: A Case of Phaethon-Geminid Complex [#6220] Mineralogical study of primitive achondrites and astronomical observation of Phaethon-Geminid-Complex showed that an incipient partial melting may have occurred in the active asteroid Phaethon.

3:20 p.m. Sirono S. * Numerical Simulation of Heat Conduction in Regolith Material [#6108] The surface temperature distribution of an asteroid depends on the thermal conductivity of the surface material. Here I conducted a numerical simulation of fine powder, and determined the packing fraction dependence.

3:30 p.m. von Allmen P. * Lee S. Keihm S. Kamp L. Hofstadter M. Gulkis S. Effect of Internal Heat Conduction on the Surface Temperature and Outgassing Rate for 67P/Churyumov-Gerasimenko [#6383] We have computed the 3-Dimensional thermal profile of comet 67P/Churyumov-Gerasimenko and studied the effect of internal thermal conductance on surface temperature and radiative emission in the spectral range that will be measured by MIRO on Rosetta.

3:40 p.m. Kossacki K. J. * Szutowicz S. Brightening of Comet 29P/Schwassmann-Wachmann 1: Dependence on the Nucleus Structure [#6145] Comet 29P/Schwassmann-Wachmann 1 is famous for its repeated outbursts - the total brightness increases by 2 to 5 mag. We present numerical simulations of the activity of model nuclei and discuss compositions necessary for multiple explosions.

3:50 p.m. Coffee Break