Asteroid 2008 TC3 and the Fall of Almahata Sitta, a Unique Meteorite Breccia

On October 6, 2008, the small (~4 m) asteroid 2008 TC3 was discovered and predicted to hit Earth within ~19 hours. Photometric data and a refl ectance spectrum were obtained. The asteroid fragmented at ~37 km altitude above Sudan. Approximately 700 centimeter-sized fragments were recovered and constitute the meteorite Almahata Sitta. It is a unique meteorite breccia, consisting of ~50–70% ureilitic materials, plus samples of nearly every major chondrite group. The refl ectance spectrum of 2008 TC3 is closest to that of F-class asteroids, not previously associated with any meteorite type. 2008 TC3/Almahata Sitta records a complex history of fragmentation, migration, and reaccretion of materials in the Solar System.