Forum Springer Astron. Astrophys.
Forum Whats New Search Orders

Astron. Astrophys. 339, L9-L12 (1998)

Next Section Table of Contents

Letter to the Editor

Evidence for water ice and estimate of dust production rate in comet Hale-Bopp at 2.9 AU from the Sun *

E. Lellouch 1, J. Crovisier 1, T. Lim 2, 3, D. Bockelée-Morvan 1, K. Leech 2, M.S. Hanner 4, B. Altieri 2, B. Schmitt 5, F. Trotta 5 and H.U. Keller 6

1 Observatoire de Paris-Meudon, F-92195 Meudon, France
2 ISO Science Operations Centre, Astrophysics Division of ESA, Villafranca, Spain
3 Queen Mary & Westfield College, University of London, London, UK
4 Jet Propulsion Laboratory, Pasadena, CA 91109, USA
5 Laboratoire de Glaciologie et Géophysique de l'Environnement, Saint Martin d'Hères, France
6 MPI für Aeronomie, Postfach 20, D-37189 Katlenburg-Lindau, Germany

Received 2 July 1998 / Accepted 14 September 1998


We report observational evidence for water ice in comet C/1995 O1 (Hale-Bopp) when it was at 2.9 AU from the Sun, from emission features at 44 and 65 µm, and possibly an absorption feature at 3.1 µm, observed with ISO/LWS and PHT. We find that icy grains have mean radii of 15 µm within a factor of 2, lifetimes of [FORMULA] 2 days, a temperature of [FORMULA] 153 K, and a total mass of [FORMULA]2[FORMULA]109 kg. From investigation of the continuum spectrum at 43-195 µm, we also infer a production rate of large particles ([FORMULA] 100 µm) dust of about 4[FORMULA]104 kg s-1.

Key words: comets: general – comet: individual: C/1995 O1 (Hale-Bopp) – infrared: solar system

* Based on observations with ISO, an ESA project with instruments funded by ESA Member States (especially the PI countries: France, Germany, the Netherlands and the United Kingdom) and with participation of ISAS and NASA.

Send offprint requests to: J. Crovisier

This article contains no SIMBAD objects.


Next Section Table of Contents

© European Southern Observatory (ESO) 1998

Online publication: September 30, 1998