THE NEW WAR IN SPACE

摘要

A typical scene from the conflict in Afghanistan, where for the first time space―specifically, more than one hundred orbiting military satellites―has been a centerpiece of the war machine: A soldier on the ground spots a Taliban target. With a lightweight, handheld Global Positioning System (GPS) receiver known as a "plugger," he uses the constellation of GPS satellites to calculate the longitude and latitude of his mark and phones in the coordinates, via satellite, to an air base in Florida. From there, an alert is sent to commanders in Saudi Arabia, who direct a Predator drone to fly over the Taliban site and relay real-time video of the scene―again, via satellite. The target is approved for bombing, and a B-52 pilot, cruising more than 20,000 feet overhead, safely out of range of antiaircraft missiles, punches the GPS coordinates into the computer of a Joint Direct Attack Munitions (JDAM) bomb before releasing it. The bomb uses its own GPS receiver to careen Earthward toward the target, exploding within a few feet of it. The whole process takes only minutes, not days as in previous wars. And the $20,000 JDAM bomb is a bargain compared with already old-fashioned $100,000 laser-guided bombs, which have difficulty finding their targets through dust, clouds, and smoke.