Near-Earth Asteroid Surface Roughness Depends on Compositional Class ∗ Lance A.M
ARTICLE IN PRESS YICAR:8714 JID:YICAR AID:8714 /FLA [m5G; v 1.65; Prn:8/10/2008; 15:52] P.1 (1-11) Icarus ••• (••••) •••–••• Contents lists available at ScienceDirect Icarus www.elsevier.com/locate/icarus Near-Earth asteroid surface roughness depends on compositional class ∗ Lance A.M. Benner a, ,StevenJ.Ostroa, Christopher Magri b, Michael C. Nolan c, Ellen S. Howell c, Jon D. Giorgini a, Raymond F. Jurgens a, Jean-Luc Margot d, Patrick A. Taylor d, Michael W. Busch e, Michael K. Shepard f a Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA b University of Maine at Farmington, 173 High Street, Preble Hall, Farmington, ME 04938, USA c Arecibo Observatory, HC3 Box 53995, Arecibo, PR 00612, USA d Department of Astronomy, Cornell University, Ithaca, NY 14853, USA e Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA f Department of Geography and Geosciences, Bloomsburg University, Bloomsburg, PA 17815, USA article info abstract Article history: Radar observations of 214 near-Earth asteroids (NEAs) reveal a very strong correlation of circular Received 21 February 2008 polarization ratio with visible–infrared taxonomic class, establishing distinct differences in the centimeter- Revised 18 June 2008 to-several-decimeter structural complexity of objects in different spectral classes. The correlation may be due to the intrinsic mechanical properties of different mineralogical assemblages but also may reflect very different formation ages and collisional histories. The highest ratios are measured for groups Keywords: Near-Earth objects associated with achondritic igneous rocky meteorites: the E class, whose parent body may be 3103 Asteroids Eger, and the V class, derived from the mainbelt asteroid (and Dawn mission target) 4 Vesta.
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