5- to 13-μm airborne observations of Comet Wilson 1986/
Abstract
Comet Wilson was observed from the Kuiper Airborne Observatory on two flights, 23.64 and 25.59 April 1987 UT (⋍3 and 5 days after perihelion) using the NASA-Ames faint object grating spectrometer. Spectrophotometric data were obtained with a 21-arc sec diameter aperture (⋍10,000 km at the comet) between 5 and 13 μm with a spectral resolving power of 50-120. Spectra of the inner coma reveal a fairly smooth continuum with evidence of silicate emission. The 5- to 8-μm color temperature of the comet was 300 ± 10 K. All three spectra obtained show an unidentified emission feature at ⋍12.25 μm and ⋍0.25 μm wide. No outburst activity was observed. We derive a simple expression relating the color temperature and equilibrium temperature to the IR absorption efficiency QIR, and use it to derive Q IR ⋍ 0.50 and mean grain radius a ⋍ 0.50 μ m.
- Publication:
-
Icarus
- Pub Date:
- December 1989
- DOI:
- 10.1016/0019-1035(89)90045-6
- Bibcode:
- 1989Icar...82..379L
- Keywords:
-
- Comet Nuclei;
- Comet Tails;
- Cometary Atmospheres;
- Emission Spectra;
- Spectrophotometry;
- Color;
- Gratings (Spectra);
- Silicates;
- Spectral Resolution;
- Astrophysics