  With the Wide-field Infrared Survey Explorer (WISE; Wright et al. 2010), we
have observed over 157,000 minor planets (Mainzer et al. 2011). Included in
these are a number of near-Earth objects, Main Belt Asteroids, and irregular
satellites which have well-measured physical properties via radar, occultation
and in situ imaging. We have used these objects to validate models of thermal
models using the WISE measurements, as well as the color corrections derived in
Wright et al. (2010) for the four WISE bandpasses as a function of effective
temperature. We have used 50 objects with diameters measured by radar,
occultation or in situ imaging to characterize the systematic errors implicit
in using the WISE data with a faceted spherical NEATM model to compute
diameters and albedos. By using the previously measured diameters and H
magnitudes with a spherical NEATM model, we compute the predicted fluxes after
applying the color corrections given in Wright et al. (2010) in the WISE bands
and compare them to the measured magnitudes. We find minimum systematic flux
errors of 5-10%, yielding minimum relative diameter and albedo errors of ~10%
and ~20%, respectively. Visible albedos for the objects are computed and
compared to the albedos at 3.4 and 4.6 microns, which contain a mix of
reflected sunlight and thermal emission for most asteroids. We derive a linear
relationship between subsolar temperature and effective temperature, which
allows the color corrections given in Wright et al. (2010) to be used for
asteroids by computing only subsolar temperature instead of a faceted thermal
model. The thermal models derived in this paper are not intended to supplant
previous measurements made using radar or spacecraft imaging; rather, we have
used them to characterize the errors that should be expected when computing
diameters and albedos of WISE asteroids using a spherical NEATM model.
