The role of micrometeorites as sources of ionization in the upper atmosphere
Abstract
We solve the simultaneous equation of continuity of charge, mass, momentum and energy of a micrometeoroid entering the upper atmosphere to study the history of its physical, dynamical and electrical properties during its flight. The analysis, which is confined to the night side of the earth, considers different initial sizes and different initial entry speeds and angles. While the polarity of the charge can change with altitude for a given micrometeoroid, the altitude range of meteoric ionization is greatly enhanced, due to thermionic emission from the frictionally heated micrometeoroid, over what it would have been if only the ablation associated ionization was considered. Also the ionization signatures of fast moving "cometary" and slow moving "asteroidal" meteoroids are different both quantitatively and qualitatively. Finally the implications of this study for atmospheric ionization for different meteor streams as well as for radar observations of meteors (e.g. the difference between "head" and "trail" radar echoes) will be considered.
- Publication:
-
35th COSPAR Scientific Assembly
- Pub Date:
- 2004
- Bibcode:
- 2004cosp...35.4401M