JIM TEDDER: CleanSpace One is not really a vacuum cleaner. It will not be used to take away space junk. But scientists plan to move it close to an old satellite that is no longer being used. Then a claw-like instrument will seize the satellite, and force it back through the atmosphere. There, the satellite will be destroyed by the heat of friction with the air.
Researchers say that all they need to do is slow down the speed of some of these unwanted objects. Once these items begin to move more slowly, they will fall back to Earth. There is little chance that they will fall through the atmosphere and harm the people or things below. Some space junk has returned to Earth, but it usually causes no harm as it falls into the ocean.
CHRISTOPHER CRUISE: The American space agency NASA and scientific organizations in other countries know that space junk is a serious problem. They are tracking the movement of over twenty thousand unwanted items circling the Earth. Some people have suggested using lasers to push the items into a lower and slower orbit.
NASA recently gave money to a South Carolina company that hopes to make a device called Eddy. That is the short name for ElectroDynamic Debris Eliminator. Eddy would work like the Swiss space cleaner. But it would use a net to catch an old satellite like a fish before sending it back through the atmosphere.
JIM TEDDER: John L. Junkins is an aerospace engineer with Texas A and M University. He says we need to remove five or six large space objects each year to stop what he calls the cascading effect. That is what happens when large objects, some as big as a bus, crash together. When they break apart, they create thousands of smaller parts that continue floating around the Earth. Professor Junkins says we would need to remove ten large pieces of space junk each year to stop the damage they might cause.
最新
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25