Mechanisms of dust emission from the surface of a cometary nucleus

doi:10.1016/0273-1177(89)90252-4

Advances in Space Research

Volume 9, Issue 3, 1989, Pages 133-137

https://doi.org/10.1016/0273-1177(89)90252-4 Get rights and content

Abstract

Cometary nuclei consist of mixtures of ices and non-volatile particulates in mass proportions of similar magnitudes. Dust is carried by the gas drag of the sublimating ices. Gas drag from free expansion of the gases from the nucleus dominates the acceleration of dust particles after their release from the surface. Significant gas pressure can build up in the ice matrix by sublimation of ices of different volatility and by non-uniform heat absorption in the ice. A dust mantle of several mm thickness which builds up over the sublimating ice surface quenches the gas outflow and causes a pressure build up across the mantle. The pressure gradient can become unstable and microeruptions of gas and dust occur. These mechanisms are in agreement with findings from recent simulation experiments in which emission speeds of 1 to 2 m/s have been observed for particles of about 10⁻⁴ m in radius

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Mechanisms of dust emission from the surface of a cometary nucleus

Abstract

Adv. Space Res.

Dust in comet P/Halley from Vega observations

Astron. Astrophys.

The dust distribution within the inner coma of comet P/Halley 1982i: encounter by Giotto's impact detectors

Astron. Astrophys.

Optical and hydrodynamic implications of comet Halley dust size distribution

Dust and neutral gas modeling of the inner atmosphere of comets

Rev. Geophys.

The dusty gas dynamics of comet heads

Thermodynamics of a dusty cometary ice I. Results

A comet model, I, The acceleration of comet Encke

Astrophys. J.

An idealized short-period comet model: surface insolation, H2O flux, dust flux and mantle evolution

Icarus

An idealized short-period comet model: surface insolation, H₂O flux, dust flux and mantle evolution