Observations of Three Stellar Occultations by Comet Hale-Bopp
Abstract
On June 12 1996 UT, three 11-12 R magnitude stars were occulted by comet Hale-Bopp. The passage of these stars through the cometary atmosphere was monitored at the Observatorio do Pico dos Dias (Brazil) using a 0.6 m telescope. We detected an absorption of starlight by the comet dust implying in a drop of (6± 1) × 10^{-2} magnitude of occulted star XPM 152-0898466 at a minimum distance of (4.3 ± 0.2)× 104 km from the central condensation. This result, combined with magnitude variations of other stars, suggests the detection of a jet in the coma. From our measurement of extinction, we infer that the opacity of the nucleus surface was τ ∼ 3. The mean geometric albedo p of dust grains is (4.5 ± 0.7) × 10^{-3}. This low albedo may suggest a difference in the grain population associated to coma and jets.
- Publication:
-
Earth Moon and Planets
- Pub Date:
- June 2017
- DOI:
- 10.1007/s11038-017-9503-z
- Bibcode:
- 2017EM&P..120....1B
- Keywords:
-
- Comets: individual:C/1995 O1 (Hale-Bopp);
- Occultations;
- Techniques: photometric;
- Opacity