A&A 489, 449-454 (2008)
Is electric charge separation the main process for kinetic energy transformation into the meteor phenomenon?P. Spurný and Z. Ceplecha
Astronomical Institute of the Academy of Sciences v.v.i., Ondřejov Observatory, Czech Republic
Received 26 April 2008 / Accepted 24 June 2008
After 3 years of systematic monitoring of fireballs by autonomous fireball observatories (AFO), millisecond flares (spikes) were recognized for the frequent and regular behavior of meteor light curves recorded with high time resolution. Also, other peculiarities in meteor motion, radiation, and ionization point to some more powerful internal processes in meteoroid interaction with the atmosphere than hypersonic aerodynamics can offer. Fragmentation of meteoroids starts at much higher altitudes than at those corresponding to aerodynamic loading. The fragility of meteoroids cannot explain this behavior, beeing also observed with the strongest bolide types (I and II). We propose triboelectricity as induced in meteoroids during their atmospheric penetration as the main process to adequately explain the meteor phenomenon, with hypersonic aerodynamics processes being only of secondary importance. Triboelectric charging may be the most important energy transfer inside a meteoroid causing internal charge differences inside different conductivity domains until discharge fragments the body. Such a process then may repeat over and over in the main body, as well as in individual fragments.
Key words: meteors, meteoroids
© ESO 2008