Spectrophotometry of OH 26.5 + 0.6 from 2 to 40 microns

Airborne and ground-based observations show that OH 26.5 + 0.6 has strong 10-μm and weak 18-μm silicate absorptions superposed on an overall energy distribution much like a blackbody. The flux level, color temperature, and depth of the 10-μm absorption varied during 2 years of observations. A model of the source as a late-type variable star that has ejected an optically thick dust shell is suggested; the mass-loss rate implied is greater than approx. 10-5 Msub solar year-1. The fact that significant flux from the source is observed between 4 and 7 μm is evidence that oxygen-rich dust has significant opacity in that wavelength range. 3 figures, 1 table