Molecular clouds: comet factories?
Abstract
Recent discoveries seem to indicate a catastrophic history of terrestrial evolution, explicable in terms of Oort cloud disturbance by molecular clouds in the Galactic disk. 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 less than or equal to 1000 km in a dense precursor state of spiral arms. If chemical and/or isotopic signatures of comets should indicate an extrasolar system source, the theory of terrestrial catastrophism may place new constraints on the understanding of the origin of molecular clouds.
- Publication:
-
IAU Colloq. 83: Dynamics of Comets: Their Origin and Evolution
- Pub Date:
- 1985
- DOI:
- 10.1007/978-94-009-5400-7_3
- Bibcode:
- 1985ASSL..115...19C
- Keywords:
-
- Catastrophe Theory;
- Comets;
- Cosmic Dust;
- Earth (Planet);
- Micrometeorites;
- Molecular Clouds;
- Capture Effect;
- Geochemistry;
- Interstellar Matter;
- Milky Way Galaxy;
- Oort Cloud;
- Planetary Evolution;
- Solar System;
- Stellar Evolution;
- Astrophysics;
- Comets:Molecular Clouds;
- Comets:Origin;
- Molecular Clouds:Comets;
- Oort's Cloud