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Cometary Nuclei

Published online by Cambridge University Press:  19 July 2016

Hans Rickman
Hans Rickman*
Affiliation:
Astronomiska observatoriet, Box 515, S-75120 Uppsala, Sweden E-mail [email protected]

Abstract

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After a brief summary of current concepts on cometary nuclei, resulting from recent advances in observational techniques and laboratory experiments on cometary analogue materials, some of the outstanding problems facing theoretical modelling and interpretations of the new data is described. Emphasis is placed on the outgassing of species more volatile than water over the history of cometary nuclei, the structure of the nuclei in terms of porosity and tensile strength on a variety of different scales, and the volumetric importance and distribution of the refractory “dust” component. Near-surface interactions of dust grains and outflowing gas may be associated with the formation of large dust aggregates and mantling of the nuclei.

Type
Physical Observations and Modeling
Information
Symposium - International Astronomical Union , Volume 160: Asteroids, Comets, Meteors 1993 , 1994 , pp. 297 - 312
Copyright
Copyright © Kluwer 1994 

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