AIR & SPACE MAGAZINE

A Rare Space Rock Gets Even Rarer

An extremely uncommon type of asteroid is found in the Nubian Desert

March 25, 2009

Muawia Shaddad of the University of Khartoum, Sudan and researcher Peter Jenniskens with students at the scene of a meteorite find in Sudan.

For the first time, scientists have recovered pieces of a rock tracked all the way from space to its meteoric demise in Earth’s atmosphere. And for the first time, Westerners are hearing how that fireball (which we wrote about in our April/May 2009 issue) appeared to people on the ground in northern Sudan when it came screaming in last October.

According to Peter Jenniskens, a researcher at the SETI Institute in Mountain View, California, people all over that part of Sudan were just returning from morning prayers when “The whole landscape lit up. It was a very frightening event.”

NASA scientists had predicted the impact—a first—and knew where to direct Jenniskens when he called weeks later to ask where to search for meteorites on the ground. When he arrived in December at the Nubian desert location (near train Station 6, between Wadi Halfa and Khartoum), along with a group of University of Khartoum students led by Muawia Shaddad, it took only two hours of searching to locate pieces of the object formerly known as 2008 TC3. (The first fragment was discovered by a student named Mohammad Alameen, who Jenniskens said was particularly adept at finding them). A total of 47 fragments were recovered, adding up to just under nine pounds of material.

Mike Zolensky, a meteorite expert at NASA’s Johnson Space Center in Houston, never imagined that any pieces of 2008 TC3 would be found. Because of the remote location, he assumed they were “lost and gone forever.” But not only has he been able to study the Sudan meteorites in his lab, they turn out to be from an extremely rare type of asteroid. In fact, there weren’t even samples of this type in any of the world’s meteorite collections.

The evidence suggests that these bits of rock were once part of a much larger body that experienced volcanism in its distant past. And based on its rare spectral type, a known asteroid with a similar spectrum, which goes by the name of 1998 KU2, has already been identified as a possible source for 2008 TC3.

Not a bad scientific return for something that wasn’t even planned.

The meteorites, by the way, have been named Almahata Sitta—Arabic for “Station 6.”