Multi-wavelength observations of Asteroid 2100 Ra-Shalom
We observed near-Earth asteroid (NEA) 2100 Ra-Shalom over a six-year period, obtaining rotationally resolved spectra in the visible, near-infrared, thermal-infrared, and radar wavelengths. We find that Ra-Shalom has an effective diameter of D = 2.3 ± 0.2 km, rotation period P = 19.793 ± 0.001 h, visual albedo p = 0.13 ± 0.03, radar albedo over(σ, ̂) = 0.36 ± 0.10, and polarization ratio μ = 0.25 ± 0.04. We used our radar observations to generate a three-dimensional shape model which shows several structural features of interest. Based on our thermal observations, Ra-Shalom has a high thermal inertia of ∼10 J m s K , consistent with a coarse or rocky surface and the inferences of others [Harris, A.W., Davies, J.K., Green, S.F., 1998. Icarus 135, 441-450; Delbo, M., Harris, A.W., Binzel, R.P., Pravec, P., Davies, J.K., 2003. Icarus 166, 116-130]. Our spectral data indicate that Ra-Shalom is a K-class asteroid and we find excellent agreement between our spectra and laboratory spectra of the CV3 meteorite Grosnaja. Our spectra show rotation-dependent variations consistent with global variations in grain size. Our radar observations show rotation-dependent variations in radar albedo consistent with global variations in the thickness of a relatively thin regolith. © 2007 Elsevier Inc. All rights reserved. eff v OC c 3 -2 -0.5 -1
Shepard, Michael K.; Clark, Beth Ellen; Nolan, Michael C.; Benner, Lance A.M.; Ostro, Steven J.; Giorgini, Jon D.; Vilas, Faith; Jarvis, Kandy; Lederer, Susan; Lim, Lucy F.; McConnochie, Tim; Bell, James; Margot, Jean Luc; Rivkin, Andrew; Magri, Christopher; Scheeres, Daniel; and Pravec, Petr, "Multi-wavelength observations of Asteroid 2100 Ra-Shalom" (2008). Faculty Articles Indexed in Scopus. 1712.