Force of Gravity

Gen. William Shelton, head of Air Force Space Command, is a fan of the movie Gravity. In it, a cloud of shrapnel resulting from a Russian anti-satellite test races around the planet at thousands of miles an hour, wrecking a space shuttle and leaving star Sandra Bullock as an orbiting castaway. Shelton forgives the movie’s scientific inaccuracies, but said in an Oct. 25 interview the film correctly portrays “what orbital debris can do” to delicate satellites, spacecraft, and the International Space Station: rip them to pieces and create even more deadly, high-speed space junk. Not only that, he said, but the movie underscores the fact that such a cloud in orbit keeps coming around “every 90 minutes or so,” creating a lasting hazard to space travel. It falls on AFSPC “to precisely track that stuff,” said Shelton, a job made tougher by funding shortfalls for space surveillance inflicted by the budget sequester. A new Space Fence—the contract for which is on hold until next spring—would allow AFSPC to track objects smaller than 10 cm in size. Without it, AFSPC would be blind to about 470,000 of the estimated 500,000 or so man-made objects on orbit, said Shelton. In the movie, it’s Air Force Space Command that issues the warning about the new debris field racing toward the astronauts.