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EISCAT observations of meteoric fragmentation. Johan Kero, Csilla Szasz and Asta Pellinen-Wannberg (Swedish Institute of Space Physics, Kiruna, Sweden) Gudmund Wannberg and Assar Westman (EISCAT Scientific Association, Kiruna, Sweden). Outline of the talk. Meteoric fragmentation processes
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EISCAT observations ofmeteoric fragmentation Johan Kero, Csilla Szasz and Asta Pellinen-Wannberg (Swedish Institute of Space Physics, Kiruna, Sweden) Gudmund Wannberg and Assar Westman (EISCAT Scientific Association, Kiruna, Sweden)
Outline of the talk • Meteoric fragmentation processes • From fireballs to dust... • Observations with EISCAT • Fragmentation of small meteoroids...
Optical brightness pulsations 2004-11-21 Leonid campaign with ALIS ACKNOWLEDGEMENTS: Björn Gustavsson and the ALIS team
Fireball flickering Peekskill, October 9, 1992
Forms of fragmentation Table from Bronshten, Physics of Meteoric Phenomena, Kluwer, 1983
EISCAT UHF: 2004-12-21 2005-06-21 2005-09-22 (?) EISCAT VHF: 2003-11-26
Assumption:One meteoroid broke up into two major fragments Conclusions that may be drawn under the assumption is that the separation... ...distance was increasing with constant acceleration 0.88 km/s2 ...occurred 0.1 s eller 4 km before they reached the centre of the radar beam ...distance was 1.6 m when they entered the radar beam ...distance was 9.6 m when they left the radar beam photo: Csilla Szasz