This illustration shows a possible story of the origin of the Almahata Sitta meteorites, adapted from the LPSC presentation by Jason Herrin (NASA Johnson Space Center) and colleagues. Follow the arrows clockwise from the upper left. Researchers propose that the story begins with a carbonaceous-chondrite-like parent body that was heated and partially melted. This hot body was smashed to smithereens by a major impact and the wreckage cooled and was mixed with debris from other asteroidal collisions. The re-accreted debris assembled into a rubble pile of all sorts of materials, with a regolith accumulated on its surface. Further impacts ejected debris off this rubble pile, sending our asteroid 2008 TC3 careening through space and eventually through Earth's atmosphere where it broke apart and scattered itself in the Nubian Desert.
Summary of Almahata Sitta meteorite (and additional documents). Highlights from the article...
Almahata Sitta is the name identifying the collection of meteorite remnants of the first observed fall of a tracked asteroid, 2008 TC3. Ground-based observatories, orbiting satellites, a pilot of a commercial airline flight, and eyewitnesses of the fireball in the Nubian Desert of northern Sudan all observed evidence of the spectacular events on October 6, 2008. The first meteorites were recovered two months later in Sudan by students and staff from the University of Khartoum (Sudan) led by Dr. Muawia Shaddad and further guided by Dr. Peter Jenniskens of the SETI Institute and NASA Ames Research Center (Mt. View, California). A session at the 41st Lunar and Planetary Science Conference held March 1-5, 2010 focused on ureilitic asteroids and insights from Almahata Sitta, and forms the basis for this article. Rather than discuss the results of each of the talks and posters presented at the conference, I highlight what makes the impact, recovery, and characterization of the ureilite meteorite fragments so outstanding. The complete listing of authors and topics is available in the conference program
Session at the (2010) 41st Lunar and Planetary Science Conference-- Ureilitic Asteroids: Insights from Almahata Sitta Full set of abstracts (pdf) from talks and links to posters.
Asteroid, Meteor, Meteorite --Short Slide Summary (with accompanying notes).
Link: Article
Link: PDF of Article
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