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Aspects of The Terrestrial Influx of Small Meteoroids

Published online by Cambridge University Press:  14 August 2015

A.D. Taylor  and
W.G. Elford
A.D. Taylor
Affiliation:
Department of Physics and Mathematical Physics University of Adelaide, Adelaide, 5005, South Australia
W.G. Elford
Affiliation:
Department of Physics and Mathematical Physics University of Adelaide, Adelaide, 5005, South Australia

Abstract

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This paper briefly summarises the contribution to the understanding of meteoroids and their orbits from recent radar studies of meteors. New data from VHF and UHF observations indicates that some meteoroids are ablating at heights up to 160 km and modelling work suggests that such meteoric ionization can only be deposited by meteoroids that ablate at temperatures below 1000° K. Meteoroids with entry speeds well in excess of 100 km/s are clearly interstellar and some tentative sources have been identified. The distributions of the orbital elements of earlier data have been reanalysed in the light of a new understanding of the selection effects in those radar studies, and the presence of a significant set of retrograde orbits identified. The new technique of observing meteors ‘coming down the radar beam’ has led to very accurate measures of deceleration and detailed analysis of fragmentation events.

Type
II. Joint Discussions
Information
Highlights of Astronomy , Volume 11 , Issue 1: Highlights of Astronomy. As presented at the XXIIIrd General Assembly of the IAU (Part A), 1997 , 1998 , pp. 239 - 245
Copyright
Copyright © Kluwer 1998

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