U.S. space expert: Debris from satellites collision likely be thousands

Source: Xinhua | 02-12-2009 16:08

WASHINGTON, Feb. 12 (Xinhua) -- Debris generated in Tuesday's collision between a U.S. satellite and a Russian satellite will likely be in the thousands, a U.S. space expert has said.

The collision, first-ever of its kind, occurred at 11:55 a.m. EST (1655 GMT) Tuesday in space nearly 800 km over Russia's Siberia, spewing a pair of massive debris clouds and posing a slight risk to the international space station, NASA said Wednesday.

It involved a 560-kg U.S. Iridium commercial satellite launched in 1997, and a 900-kg Russian satellite launched in 1993 and presumed non-operational.

"Right now, they're definitely counting dozens," Mark Matney, an orbital debris scientist at NASA's Johnson Space Center in Houston, was quoted Wednesday by local media as saying.

"I would suspect that they'll be counting hundreds when the counting is done," he said.

As for pieces of the size of micrometers, the count will likely be in the thousands, he added.

Meanwhile, Nicholas Johnson, chief scientist of NASA's Orbital Debris Program Office at Johnson Space Center, said it was uncertain how much new debris had been created by the crash.

"It takes a while for the debris to spread out and for us to get an accurate head count," Johnson said.

According to an email alert issued by NASA Wednesday, Russia's Cosmos 2251 satellite slammed into the Iridium 33 satellite at 11:55 a.m. EST (1655 GMT). The incident was observed by the U.S. Defense Department's Space Surveillance Network, which later was tracking two large clouds of debris.

The cause of the collision is still unknown.

Editor:Zhang Pengfei