Earth, Moon, and Planets

, Volume 78, Issue 1, pp 5–11

Long-term Evolution of the Outgassing of Comet Hale-Bopp From Radio Observations

Authors

  • N. Biver
    • Observatoire de Paris-Meudon
  • D. Bockelée-Morvan
    • Observatoire de Paris-Meudon
  • P. Colom
    • Observatoire de Paris-Meudon
  • J. Crovisier
    • Observatoire de Paris-Meudon
  • B. Germain
    • Observatoire de Paris-Meudon
  • E. Lellouch
    • Observatoire de Paris-Meudon
  • J. K. Davies
    • Joint Astronomy Centre
  • W. R. F. Dent
    • Joint Astronomy Centre
  • R. Moreno
    • Institut de Radio Astronomie Millimétrique
  • G. Paubert
    • Institut de Radio Astronomie Millimétrique
  • J. Wink
    • Institut de Radio Astronomie Millimétrique
  • D. Despois
    • Observatoire de Bordeaux
  • D. C. Lis
    • Caltech
  • D. Mehringer
    • Caltech
  • D. Benford
    • Caltech
  • M. Gardner
    • Caltech
  • T. G. Phillips
    • Caltech
  • M. Gunnarsson
    • Uppsala Astronomiska Observatorium
  • H. Rickman
    • Uppsala Astronomiska Observatorium
  • A. Winnberg
    • Onsala Space Observatory
  • P. Bergman
    • Onsala Space Observatory
  • L. E. B. Johansson
    • Onsala Space Observatory
  • H. Rauer
    • Institut für PlanetenerkundungDLR
Article

DOI: 10.1023/A:1006229818484

Cite this article as:
Biver, N., Bockelée-Morvan, D., Colom, P. et al. Earth, Moon, and Planets (1997) 78: 5. doi:10.1023/A:1006229818484

Abstract

C/1995 O1 (Hale-Bopp) has been observed on a regular basis since August 1995 at millimetre and submillimetre wavelengths using IRAM, JCMT, CSO and SEST radio telescopes. The production rates of eight molecular species (CO, HCN, CH3OH, H2CO,H2S, CS, CH3CN,HNC) have been monitored as a function of heliocentric distance(rh from 7 AU pre-perihelion to 4 AU post-perihelion. As comet Hale-Bopp approached and receded from the Sun, these species displayed different behaviours. Far from the Sun, the most volatile species were found in general relatively more abundant in the coma. In comparison to other species, HNC, H2CO and CS showed a much steeper increase of the production rate with decreasing rh. Less than 1.5 AU from the Sun, the relative abundances were fairly stable and approached those found in other comets near 1 AU.

The kinetic temperature of the coma, estimated from the relative intensities of the CH3OH and CO lines, increased with decreasing rh, from about10 K at 7 AU to 110 K around perihelion. The expansion velocity of the gaseous species, derived from the line shapes, also increased with a law close torh3.

CometsC/1995 O1 (Hale-Bopp)radio observationsmolecules

Copyright information

© Kluwer Academic Publishers 1997