Irradiation Effects on Comets and Cometary Debris

  • G. Strazzulla
  • R. E. Johnson
Part of the Astrophysics and Space Science Library book series (ASSL, volume 167)


For the last 10 years, many experimental results have been obtained on the chemical and physical changes induced by ion and electron irradiation of materials relevant to comets. Those results are reviewed here, together with their physical interpretation and their relevance for cometary astrophysics. Cometary material is, from the time of its origin, altered by the large amount of energy deposited by energetic ions. Four phases of the irradiation history are considered: the pre-cometary phase, during which interstellar dust is bombarded by cosmic-ray ions; the accretion phase, during which comets are built up, possibly in an environment rich in fast ions (T-Tau phase); the cometary phase, during which the outer layers of the comets are irradiated by galactic ions in the Oort cloud; and the post-cometary phase, during which dust, lost from the comet, is bombarded by solar ions.

The relevant applications of laboratory results are reviewed. In particular, the ability of ion irradiation of simple carbon-containing ices to produce complex refractory organic materials is discussed. In the Oort cloud, this process can occur several meters into the surface, so that the buildup of a stable organic crust may occur. A comparison of ion irradiation at various stages is also made with other models for the production of organics.


Solar Wind Solar System Cometary Nucleus Interstellar Dust Oort Cloud 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media Dordrecht 1991

Authors and Affiliations

  • G. Strazzulla
    • 1
  • R. E. Johnson
    • 2
  1. 1.Istituto di AstronomiaCitta’ UniversitariaCataniaItaly
  2. 2.Dept. of Engineering and Engineering PhysicsUniversity of VirginiaCharlottesvilleUSA

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