0470253 - ASÚ 2017 RIV GB eng C - Konferenční příspěvek (zahraniční konf.)
Borovička, Jiří
Are some meteoroids rubble piles?
Asteroids: New Observations, New Models. Cambridge: Cambridge University Press, 2016, s. 80-85. Proceedings of the International Astronomical Union, IAU S318. ISBN 9781107138254. ISSN 1743-9213.
[Symposium of the International Astronomical Union /318./. Honolulu (US), 03.08.2015-07.08.2015]
Grant CEP: GA ČR(CZ) GAP209/11/1382
Institucionální podpora: RVO:67985815
Klíčová slova: meteors * meteoroids * asteroids
Obor OECD: Astronomy (including astrophysics,space science)
DOI: https://doi.org/10.1017/S174392131500873X

The possibility that some meteoroids in the size range 1 - 20 meters are rubble piles i.e. assembles of boulders of various sizes held together only by small van der Waals forces, is investigated. Such meteoroids are expected to start disrupting into individual pieces during the atmospheric entry at very low dynamic pressures of ~ 25 Pa, even before the onset of ablation. The heterogeneous bodies as Almahata Sitta (asteroid 2008 TC3) and Benešov are primary candidates for rubble piles. Nevertheless, by analyzing the deceleration, wake, and light curve of the Benešov bolide, we found that the meteoroid disruption started only at a height of 70 km under dynamic pressure of 50 kPa. No evidence for a very early fragmentation was found also for the Chelyabinsk event.
Trvalý link: http://hdl.handle.net/11104/0267943