Main Belt Asteroids with WISE/NEOWISE: Near-Infrared Albedos

Understand

We present revised near-infrared albedo fits of 2835 Main Belt asteroids observed by WISE/NEOWISE over the course of its fully cryogenic survey in 2010.

• These fits are derived from reflected-light near-infrared images taken simultaneously with thermal emission measurements, allowing for more accurate measurements of the near-infrared albedos than is possible for visible albedo measurements.
• As our sample requires reflected light measurements, it undersamples small, low albedo asteroids, as well as those with blue spectral slopes across the wavelengths investigated.
• We find that the Main Belt separates into three distinct groups of 6%, 16%, and 40% reflectance at 3.4 um.