July 30, 2010

Chinese Satellite Debris No Longer A Threat To ISS

Debris from a Chinese satellite that had concerned scientists earlier Thursday is now not expected to pose a threat to the International Space Station, according to NASA officials.

NASA said the debris will come no closer than 5 miles to the space station. It said no crew action is necessary and operations will not be affected. Mission Control gave the Expedition 24 crew the all-clear at 12:45 pm EDT.

Earlier on Thursday, NASA reported that a piece of debris from a Chinese satellite may pass close enough to the station to require astronauts to take shelter in their Soyuz spacecraft.

NASA said it was difficult to precisely track the object and expected its closest pass to occur at 1:47 pm EDT. Mission Control in both US and Russia were keeping a close eye on the debris.

Satellites and spacecraft are constantly threatened by space debris, which can be traveling at speeds that exceed 17,000 mph, according to the NASA website.

"The greatest risk to space missions comes from non-trackable debris," Nicholas Johnson, NASA chief scientist for orbital debris, told CNN on Thursday.

More than half a million pieces of "space junk" are tracked as they orbit Earth, according to NASA's website. Although most of the debris is quite small, as many as 20,000 pieces are larger than a softball, which NASA keeps track of due to the serious threat they pose to the space station.

NASA has created guidelines -- or flight rules -- on how to deal with potential collision threats. These flight rules are used to assess whether the threat of an approaching orbital piece of space junk is sufficient to warrant evasive maneuvers or precautions to ensure the safety of space station crew or equipment, according to the site.

Three American astronauts and three Russian cosmonauts are currently on the International Space Station - Americans are Tracy Caldwell Dyson, Shannon Walker and Douglas H. Wheelock; Russians are Skvortsov Alexander Alexandrovich, Kornienko Mikhail Borisovich and Fyodor Nikolayevich Yurchikhin.


On the Net: