Long-term dynamics of bright bolides
L. Foschini 1,
P. Farinella 2,
Ch. Froeschlé 3,
R. Gonczi 3,
T.J. Jopek 4 and
P. Michel 5
Received 3 June 1999 / Accepted 8 September 1999
We have integrated backward and forward in time the orbits of 20 very bright bolides (with visual magnitude brighter than -10) over a time span of 5 Myr or more. The sample was mainly selected among events observed during the period between 1993 and 1996, but we have included also three older, particularly interesting events (Abee, 1952; Glanerbrug, 1990; and EN220991, 1991). For a large part of the sample, the orbit is known with sufficient accuracy from the reduction and analysis of photographic data. However, there are also some cases in which lower-accuracy orbital data were derived from other techniques, such as visual, seismic, and radar observation. For these events we have used two or three alternative initial orbits, consistent with the existing uncertainty. The results of our integrations show a great diversity of orbital evolution patterns, consistent with the behaviour of larger near-Earth objects. The most frequent fate ( of the cases) is solar collision, followed by hyperbolic ejection (), and the average dynamical lifetime is of the order of 10 Myr. Three bolides either have initially or achieve later Aten-type or AU orbits, similar to the fraction of such objects in the near-Earth asteroid population. Only 2 bolides have a clear comet-like dynamical behaviour dominated by Jovian encounters, although ablation properties indicate that the fraction of very weak bolides is probably higher.
Key words: meteors, meteoroids minor planets, asteroids celestial mechanics, stellar dynamics methods: numerical
Send offprint requests to: P. Farinella (email@example.com)
This article contains no SIMBAD objects.
© European Southern Observatory (ESO) 2000
Online publication: December 17, 1999