Infrared photometry of comet Wilson (1986l) at two epochs

1-20 micron filter photometry of comet Wilson (1986l) was obtained on May 29 - June 2, 1987 (r = 1.36 AU) and January 11 -14, 1988 (r = 3.75 AU) at the NASA Infrared Telescope Facility. The thermal emission at 1.36 AU has been fit with a model for a size distribution of small absorbing grains; the size and the optical properties of the dust (color, albedo, and thermal emission spectrum) appear typical of short period comets at similar r. No 10 micron silicate feature was evident. The dust-production rate on June 1 was about 5 x 10 to the 5th g/s. The geometric albedo of comet Wilson at r = 3.75 AU appears to be higher than that of comets measured at smaller r, after phase effects have been accounted for. Such albedos seem typical of comets at larger heliocentric distances.