Littering in Outer Space
Taking out the trash at home is one thing, but taking out the trash in space? Disposing of the millions of pieces of trash floating in space, 13,000 of which measure more than 30 ft long each, is not always just a question of sanitation: it can be a question of survival. Any one of those pieces, moving at speeds of up to several thousands of miles an hour, could pierce a hole in a space shuttle or the International Space Station. And while most space trash does eventually either burn up as it enters the Earth's atmosphere or fall harmlessly into an ocean or parcel of land upon successful re-entry, the odds are favorable enough for this to be a significant concern.
Under normal circumstances, astronauts get rid of their trash by waiting for a Russian Progress supply ship to take it away or by returning it to Earth on a shuttle flight. Sounds easy enough. But how to dispose of a hulking 1,360 pound coolant storage unit? The EAS (early ammonia servicing unit), located on the outside of the space station, is about to be replaced with a newer, more powerful system, but the astronauts haven't yet figured out a way to conveniently dispose it."Is it safe for the International Space Station? Is it safe for any other orbiting vehicle? Is it safe for people on Earth? Does it make sense from an overall problematic risk standpoint?" ponders Kirk Shireman, NASA's deputy space station program manager. The solution may lie in "throwing" the unit: during a forthcoming spacewalk, three astronauts, Russian cosmonauts Fyodor Yurchikhin and Oleg Kotov and American astronaut Clay Anderson, plan on releasing the EAS from the station's surface and using a robot arm to give it a "good shove."
Engineers at the station hope that, with a speed of about 3 ft per second, the unit will be placed into an orbit so as to prevent it from colliding with the station. "Picture grabbing hold of a refrigerator. What is important is the initial velocity with which he throws it," explained Shireman.
Though certain parts of the EAS may eventually reach the planet's surface, NASA scientists say they're not too concerned: they predict it probably won't happen until at least a few months out. "I've played baseball with Clay Anderson, and I've seen him pitch. He can do this," Shireman said jokingly.
Via ::ABC News: How Do You Take Out the Garbage in Space? (news website), ::3quarksdaily: Taking Out the Trash in Space (blog)