space debris

Satellites currently must dodge an ever-growing gauntlet of other satellites and clouds of space debris, and this year the Pentagon has quietly upgraded its surveillance accordingly. The U.S. military announced yesterday that it now tracks 800 maneuverable satellites, compared to less than 100 prior to a February collision between an active U.S. satellite and a retired Russian communications satellite.

When NASA unveiled the first space shuttle in 1977, they named it Enterprise to evoke advanced technology and the promise of space flight. Now, over 30 years later, the shuttle has become the interplanetary version of the family wagon: old, but still getting the job done.

No need to don a hard hat just yet. The odds that one of the millions of pieces of trash orbiting Earth will fall and hit you are about one in a trillion, says Bill Ailor, director of the Center for Orbital and Reentry Debris Studies.

The risk that someone will get hit can run far higher, though, says Nicholas Johnson, NASA's chief scientist for orbital debris. NASA and other space agencies aim to keep the risk of injury from falling objects lower than one in 10,000. The risks typically run higher with large objects. For example, there's a one-in-1,000 shot that the Hubble Space Telescope could hit someone if it falls from orbit once it's decommissioned, so NASA will preemptively steer it into the ocean.

There is a scene in Dances with Wolves after Costner's character has arrived at the deserted Dakota base in which he discovers the company's garbage pile. He gives it a disappointing, scrutinizing look as he recognizes it's another harbinger of what is to come for the plains and its people. Fast forward 150 years to a different kind of frontier: space, in near-Earth orbit. There, we find a similar garbage pile, only this one is traveling at 30,000 miles per hour and threatens all the satellites and telescopes and space stations floating about.

Scenario 1: Sport


Sixty miles up, you sit in a chair on the open deck of a small rocket, admiring the stars above, the Earth far, far below. The vacuum beyond your visor is cold, but it would boil your blood if your pressure suit failed. You give your parachute straps a reassuring pat. It's utterly silent. Just you and your fragile body, hovering alone above the Earth. "Space Diver One, you are go," crackles a voice in your ear, and you undo your harness and stand up. There's nothing for it now: You paid a lot of money for this.