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Characterization of Binary and Triple Systems in the Near-Earth, Main Belt, and Trans-Neptunian Populations

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Characterization of Binary and Triple Systems in the Near-Earth, Main Belt, and Trans-Neptunian Populations Asteroids, Comets, Meteors (2012) 6297.pdf CHARACTERIZATION OF BINARY AND TRIPLE SYSTEMS IN THE NEAR-EARTH, MAIN BELT, AND TRANS-NEPTUNIAN POPULATIONS. J. L. Margot1,2, J. Fang2, S. Naidu1, M. Busch1, P. Rojo3, 1Department of Earth and Space Sciences, University of California, Los Angeles (595 Charles Young Drive East, Los Angeles, CA 90095, [email protected]), 2Department of Physics and Astronomy, University of California, Los Angeles, 3Departamento de Astronomia, Universidad de Chile, Santiago, Chile. The study of multiple asteroid systems is quite powerful as it can illuminate physical properties, me- chanical properties, thermal properties, composition, interior structure, formation processes, and evolution- ary processes. Our group uses a variety of imaging data (radar, adaptive optics, Hubble) to provide firm data constraints on the physical and dynamical proper- ties of minor planets. We will describe how we use these data to test theories for the formation and evolu- tion of these systems. Fang et al (2011) provided a detailed description of two triple asteroid systems in the near-Earth asteroid Figure 1: Radar image of NEA 2000 DP107, for (NEA) population, including an in-depth study of the which component shapes, masses, and densities can be dynamics: origin of orbital eccentricities and inclina- derived with great precision. VLT adaptive optics im- tions, evolutionary processes, stability. age of MBA 702 Alauda, a binary asteroid with one of the highest known primary-to-secondary mass ratios. Naidu et al (2011) conducted a similar study for NEA 2000 DP107 and presented a 1999 KW4-class References: characterization of the binary with accurate component shapes, masses, and densities. Data acquired over a J. Fang el al. Orbits of near-Earth asteroid triples decade allows us to quantify dynamical phenomena 2001 SN263 and 1994 CC: properties, origin, and evo- such as libration of the secondary and orbital evolu- lution. Astronomical Journal 141, 154, 2011. tion. J. Fang and J. L. Margot. Near-Earth Binaries and Fang and Margot (2011) examined active processes Triples: Origin and Evolution of Spin-Orbital Proper- in the lives of binary and triple NEAs, including tidal ties. Astronomical Journal 143, 24, 2012. processes, radiative processes, three-body interactions, and close planetary encounters. By examining the spin J. L. Margot et al. Kuiper Belt Binaries: Masses, and orbital properties of all well-characterized NEA Colors, and a Density. BAAS 37, 2005. binaries and triples, we can perform detailed hypothe- sis testing regarding the formation and evolution pro- S. P. Naidu et al. Binary Near-Earth Asteroid 2000 cesses of multiple asteroids. DP107: Component Shapes, Mutual Orbit, Evolution. EPSC-DPS Joint Meeting, 2011. Rojo and Margot (2011) used adaptive optics data to characterize a binary main belt asteroid (MBA) with P. Rojo and J. L. Margot. Mass and density of B- one of the highest known primary-to-secondary mass- type asteroid (702) Alauda. Astrophysical Journal 727, ratios, 702 Alauda. Additional observations at Keck 69, 2011. and the Very Large Telescope are being used for de- tailed analyses of other binary and triple MBAs. Our Hubble Space Telescope observations of the triple trans-Neptunian object 1999 TC36 (Margot et al 2005), coupled with additional observations, have the potential to dramatically improve the knowledge of that system and to discriminate between formation processes. .
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