Since we began exploring outer space, we have been trashing the place.

Call it "space debris" or "space junk," there is enough material floating through space or orbiting the Earth that some companies believe they can build a business around it, according to an article in Nature News. Space debris can be natural, such as meteroids, or human-made, such as old satellites or parts of spacecraft. A single piece of space debris can travel at speeds up to 17,500 miles per hour, well enough to damage a spacecraft or satellite in a collision, according to NASA.

So far, the U.S. military is the world's main monitor of free-floating junk, and it warns governments or other operators of hazards. But companies such as Pennsylvania's Analytical Graphics is developing their own junk-watching capability based on a large network of "off-the-shelf" sensors that currently tracks more than 6,000 objects in the Earth's orbit, up to 42,000 kilometers above the Earth's surface. That's far less than the 23,000 objects the military tracks with its multi-million-dollar telescopes and instruments, but Analytical Graphics is betting its system will prove useful to operators that want to protect the investments they launch into space.