Composition and Physical Properties of Comets

  • Hans Rickman
Part of the Astrophysics and Space Science Library book series (ASSL, volume 227)


This review concentrates on observational evidence, including some relevant modelling efforts to interpret the data, on the chemical and structural properties of cometary nuclei. Special attention is paid to the ratio of refractories to volatiles in cometary material, the microstructure of the icy component and mechanism whereby very volatile species can be produced, and the buildup of cometary nuclei in terms of material strength and density. The possible occurrence of primordial heterogeneity and likely development of radial differentiation as an effect of thermal evolution are also briefly discussed, in particular in view of the size dependence of such effects. Cometary nuclei are found to be, most likely, dominated (though not by a wide margin) by refractories, very porous and fragile (though monolithic rather than of rubble-pile structure), and generally quite homogeneous except for dust mantling and the effects of radial migration of volatiles in the interiors.


Solar Nebula Cometary Nucleus Meteor Stream Perihelion Distance Cometary Material 
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Copyright information

© Springer Science+Business Media Dordrecht 1998

Authors and Affiliations

  • Hans Rickman
    • 1
  1. 1.Astronomiska ObservatorietUppsalaSweden

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