Monday, March 26, 2012
Space is full of junk.
When the astronauts went to the moon, they left trash there. Very expensive trash. The amount of trash in space is becoming a problem. And with more satellites going up every year, the amount is growing quickly. It is estimated that there is nearly 2 million kilograms of space junk in low Earth orbit. Much of this is being tracked as it orbits the earth. There are about 10,000 objects that are about the size of a grapefruit or larger.
If a piece that large were to hit a satellite or space station, it could do some serious damage. If an object a centimeter or larger, moving at 40,000 kilometers an hour, were to hit something, it would be the equivalent of throwing a bowling ball at speeds of 500 kilometers an hour at a human being. The Space Shuttle has returned with large chips in its windshield (I don't think there are winds in space, but you know what I mean) that came from colliding with a speck. Impacts from space junk have been thought to disable two satellites.
So what can we do? Most of this junk will eventually fall to Earth. However, this can take a while, and it's a hazard to astronauts. There is a 1 in 91 chance that an astronaut could be hit with a piece big enough to penetrate their suit. The astronaut would be very lucky to survive. As if their jobs weren't already full of dangers.