Ultraviolet Spectra and Geometric Albedos of 45 Asteroids

Abstract

Spectral reflectances and geometric albedos between 2300 and 3250 Å are determined for 45 asteroids from data acquired by the International Ultraviolet Explorer satellite. The geometric albedos are consistently tow, ranging from ∼0.02 for C-type asteroids to ∼0.08 for M-type asteroids. An exception is the single E-type asteroid (44 Nysa) with a geometric albedo of 0.3 at 2950 A. We find that the three major asteroid taxonomic classes persist into the UV. The taxonomic classes are distinguished primarily by their albedos, but S types are generally redder than C or M types. The first ultraviolet phase curves of asteroids are presented.