NEOWISE Studies of Asteroids with Sloan Photometry: Preliminary Results

The Astrophysical Journal (Impact Factor: 5.99). 10/2011; 745(1). DOI: 10.1088/0004-637X/745/1/7
Source: arXiv


We have combined the NEOWISE and Sloan Digital Sky Survey data to study the
albedos of 24,353 asteroids with candidate taxonomic classifications derived
using Sloan photometry. We find a wide range of moderate to high albedos for
candidate S-type asteroids that are analogous to the S-complex defined by
previous spectrophotometrically-based taxonomic systems. The candidate C-type
asteroids, while generally very dark, have a tail of higher albedos that
overlaps the S types. The albedo distribution for asteroids with a
photometrically derived Q classification is extremely similar to those of the S
types. Asteroids with similar colors to (4) Vesta have higher albedos than the
S types, and most have orbital elements similar to known Vesta family members.
Finally, we show that the relative reflectance at 3.4 and 4.6 $\mu$m is higher
for D-type asteroids and suggest that their red visible and near-infrared
spectral slope extends out to these wavelengths. Understanding the relationship
between size, albedo, and taxonomic classification is complicated by the fact
that the objects with classifications were selected from the
visible/near-infrared Sloan Moving Object Catalog, which is biased against
fainter asteroids, including those with lower albedos.

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