Characterization of the nucleus of comet Hale-Bopp from HST and ISO observations
Abstract
High resolution images were obtained in the visible with the Planetary Camera of the Hubble Space Telescope and "B,V,R" filters and in the thermal infrared with ISOCAM and from filters centered at 7.75, 9.62, 11.4 and 15.0 micron. The latter images were carefully processed to independently correct for the temporal evolution of the signal in each pixel. Using our standard technics, we separated the nuclear and comatic contributions to retrieve the flux from the nucleus. Two thermal models were used to interpret the infrared fluxes, the Standard Thermal Model (STM) and a mixed ice-dust model. Combining the visible and thermal data, the STM model suggests a body with a radius of 35+/-6 km with an albedo of 0.05+/-0.02 and a maximum temperature of 254 K while the mixed model indicates a larger radius 52+/-5 km and a lower maximum temperature of 192 K. The spectral energy distribution is best fit with the mixed ice-dust model with an excess at 10 micron attributed to the silicate band.
- Publication:
-
AAS/Division for Planetary Sciences Meeting Abstracts #31
- Pub Date:
- September 1999
- Bibcode:
- 1999DPS....31.2703L