Halo of Bullets

Here’s an interesting (and scary) paper from two UCSC physicists on a disastrous consequence of fighting wars in low earth-orbit:

Abstract: Many philosophers argue that one cannot derive an ?ought? from an ?is?, but sometimes science tells us things that should lead most people to the same conclusion about what ought to be done. The current debate over missile defense has failed to emphasize a crucial point: even one war in space will create a battlefield that will last forever, encasing the entire planet in a shell of whizzing debris that will thereafter make space near the earth highly hazardous for peaceful as well as military purposes. With enough orbiting debris, pieces will begin to hit other pieces, whose fragments will in turn hit more pieces, setting off a chain reaction of destruction that will leave a lethal halo around the Earth. No actual space war even has to be fought to create this catastrophe; any country that felt threatened by America?s starting to place lasers or other weapons into space would only have to launch the equivalent of gravel to destroy the sophisticated weaponry. Wise people have pointed out that missile defense will waste hundreds of billions of dollars that could be spent combating the real threats in the modern world. Short term political interests pale before the overwhelming, eternal immorality of imprisoning Earth for all future generations in a halo of bullets. This horrible crime would dishonor our ancestors, plant and animal alike, who bequeathed this beautiful blue planet to us, and cripple our descendents, who would never forgive us.

(via Prometheus)