Space debris is getting out of hand

(NASA ) As if we didn’t have enough to hand-wring about, here’s the latest from The Washington Post’s Christian Torres: “Space debris has passed the ‘tipping point,’ according to a report released Thursday by the National Research Council, which called on NASA to find ways to better monitor and clean up the orbiting junk threatening active satellites and manned spacecraft.”

The map above comes from NASA’s Orbital Debris Program Office, showing all the trash we’ve put into orbit since Sputnik — bits of satellites that have cracked apart, or old upper-launch vehicle stages left in orbit. NASA adds a delightfully snitty caption: “Note the larger population of objects over the northern hemisphere is due mostly to Russian objects in high-inclination, high-eccentricity orbits.” Russians!

The thing to freak out about is that all this debris will multiply over time. Those tiny shards are traveling fast enough (some at speeds of 22,000 mph) that they act like torpedoes, and if they collide with existing satellites, you get an explosion and then even more high-flying debris. Repeat until all of space is saturated with dangerous trash and low-earth orbit becomes unusable.

Back in the 1970s, NASA astrophysicist Donald Kessler did the math and concluded that, by 2000, this chain reaction would get out of control. Happily, it hasn’t happened yet, and there’s now a big debate about when, exactly, the cascade will start. The new National Research Council report suggests that we’re going to have big problems within 10 or 20 years. In 2009, we saw the first major collision between two intact satellites — a U.S. Iridium and an aging Russian Cosmos. The end result was 2,000 additional chunks of metal flying around the Earth. Also, in 2007, China blew up one of its own satellites to show off its weapons capabilities, which created an additional 3,000 bits of debris. Oops.

So should we worry that space will become so saturated with dangerous trash that satellites will no longer function, and we’ll have to go without GPS and cellphones? Although looking around at some of the old reports on the Inter-Agency Space Debris Coordination Committee’s Web site (yes, this exists), it seems that a number of experts think that the problem is manageable. Satellites can use their booster rockets to sidestep the debris with enough warning. We might be able to shove the really troublesome chunks off into “graveyard orbit” (22,000 miles away from the Earth). Or, alternatively, some of those old satellites contain a lot of valuable metal and parts, so someone could set up a galactic pawn shop to harvest old space trash.