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The Study of Comets at Radio Wavelengths

Published online by Cambridge University Press:  12 April 2016

J. Crovisier  and
F. P. Schloerb
J. Crovisier
Affiliation:
Observatoire de Paris-Meudon 92195 MeudonFRANCE
F. P. Schloerb
Affiliation:
Department of Physics and Astronomy, University of Massachusetts Amherst, MA 01003U.S.A.

Abstract

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Radio observations of comets complement studies at other wavelengths as well as providing certain kinds of unique information. Studies of continuum emission may probe the thermal emission of the nucleus and large-size dust particles. Spectroscopic observations of gas in the coma allow searches for parent molecular species that have no signatures in the optical spectral range. The 18-cm wavelength spectral lines of the OH radical now are relatively easy to detect, and observations of them permit long-term and short-term monitoring of the cometary gaseous output. Moreover, with the unique spectral resolution of radio techniques, aspects of the kinematics of the coma may be also studied, such as the gas expansion velocity and the anisotropy of gas production from the nucleus. In this review, we present recent results of cometary radio observations, and discuss what may be learned from such studies in the future.

Type
Section I: Observing Techniques and Interpretation
Information
International Astronomical Union Colloquium , Volume 116 , Issue 1: Comets in the Post-Halley Era , 1989 , pp. 149 - 173
Copyright
Copyright © Kluwer 1991

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