The NASA infrared telescope facility Comet Halley monitoring program. I - Preperihelion results

The results of a 1 - 20 μm infrared monitoring program on comet Halley are presented. The observations covered the time period of January 1985 to January 1986. Most of the observations presented were made with an aperture of 7 arcsec. The authors find (1) the dust production of the comet was approximately 6×10⁶g s⁻¹ at a heliocentric distance (r) of 1 AU; (2) the near-infrared colors remained constant over r = 0.90 to 2.86 AU; and (3) the albedo of the dust in the coma was 3% - 4%. The results are compared to other comets that the authors have observed previously.