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Molecular clouds: comet factories?

Published online by Cambridge University Press:  12 April 2016

S.V.M. Clube
S.V.M. Clube*
Affiliation:
Department of Astrophysics, South Parks Road, Oxford OX1 3RQ

Abstract

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Recent discoveries seem to indicate a catastrophic history of terrestrial evolution, explicable in terms of Oort cloud disturbance by molecular clouds in the Galactic disc. The problem of Oort cloud replenishment thus assumes considerable significance and reasons are given for supposing comet exchange takes place during actual penetration of molecular clouds. The number density of comets in molecular clouds, thereby implied, seems to suggest primary condensations of ≤103km in a dense precursor state of spiral arms. If chemical and/or isotopic signatures of comets should indicate an extra-Solar System source, the theory of terrestrial catastrophism may place new constraints on our understanding of the origin of molecular clouds.

Type
Section I. Origin of Comets
Information
International Astronomical Union Colloquium , Volume 83: Dynamics of Comets: Their Origin and Evolution , 1985 , pp. 19 - 30
Copyright
Copyright © Cambridge University Press 1985

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