NEOWISE Studies of Asteroids with Sloan Photometry: Preliminary Results

TL;DR

This study combines NEOWISE and Sloan data to analyze asteroid albedos and classifications, revealing diverse properties among different asteroid types and extending understanding of their spectral characteristics.

Contribution

It provides a large-scale analysis of asteroid albedos using combined infrared and optical data, highlighting new insights into taxonomic classifications and spectral properties.

Findings

Candidate S-type asteroids have moderate to high albedos.

C-type asteroids are generally dark but include higher albedo objects.

Vesta-like asteroids have higher albedos and similar orbital elements.

Abstract

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.