Scientists have announced that they have tracked an asteroid from space all the way to its impact on Earth, a first for astronomy. Space rocks are called asteroids when they are in orbit and meteorites when they land on Earth. Scientists who collect meteorites usually do not know the specific asteroid that they came from—until now.
In early October 2008, numerous Earth-based telescopes spotted the asteroid 2008 TC3 careening toward Earth. Its landing spot was calculated to be the Nubian Desert of northern Sudan. Deserts are ideal places to collect meteorites because the space rocks are easily spotted on a monochromatic surface without vegetation. But it was expected that this small asteroid would largely vaporize because of friction from air molecules upon entry.
Astronomer Peter Jenniskens of the SETI Institute in Mountain View, California, took the chance that some of the asteroid survived. He organized a search party with students and staff from the University of Khartoum, and they successfully gathered 4 kilograms of fresh black meteorite fragments from the landing site. “For the first time we can dot the line between the meteorite in our hands and the asteroid that astronomers saw in space,” said Jenniskens in a NASA press conference. The discovery has improved astronomers’ understanding of asteroids, information that may be critical if a larger, more destructive asteroid hits Earth in the future.