Keep outer space beautiful

Unfortunately, it might be too late. According to Federal and private aerospace experts (and today's Times), the junk we've been rocketing into orbit around the Earth since the space age began may be reaching a critical mass, greatly increasing chances that a speeding piece of debris will "smash a large spacecraft into hundreds of pieces and start a chain reaction, a slow cascade of collisions that would expand for centuries, spreading chaos through the heavens."

What kind of debris? Not just dead satellites of old and rocket boosters from long-ago launches, but a growing cloud of bits and pieces left over from years of Soviet and U.S. anti-satellite weapons testing from 1968 to 1986. (Recently, China got into the act, blowing one of its old satellites into at least 647 detectable pieces, and sparking an international diplomatic crisis.) Click here for a scary full-motion version of the graphic above, which is a representation of all currently trackable items in orbit around Earth.

If nothing is done, a kind of orbital crisis might ensue that is known as the Kessler Syndrome, after a former NASA official who hypothesized the scenario -- a staple of science fiction -- in which the space around Earth becomes so riddled with junk that launchings are almost impossible. Vehicles that entered space would quickly be destroyed. Is there a solution -- some cosmic vacuum that could wipe the space around Earth clean and allow us a fresh start? Not quite. Proposals include "robots that install rocket engines to send dead spacecraft careering back into the atmosphere, or ground-based lasers that could be used to zap debris." (Both sound prohibitively expensive, and a little silly. And do we really want millions of tons of space junk raining down on us, anyway?)