US Keeping Nukes in Case of ... Asteroids?

Somebody's been watching Armageddon: American nuclear authorities say they have delayed getting rid of old warhead components because they could help protect the world from killer asteroids. Authorities say the warheads are being kept "pending a senior-level government evaluation of their use in planetary defense against earthbound asteroids," reports the Wall Street Journal, which found the information "tucked away" on the 67th page of a Government Accountability Office report on the National Nuclear Security Administration.

Scientists believe it will be at least a century before any asteroids big enough to wreck the planet are close enough to worry about, but some researchers are worried about smaller asteroids and believe nuclear weapons could be an effective solution, the Atlantic reports. But that runs the risk of having radioactive debris hit Earth, and a Purdue University professor tells the Journal that there are probably better ways to ward off asteroids, including a "gravity tractor" that could change their course. Saying nukes are needed to defend the planet "may be an excuse for keeping the nuclear arsenal together," he says. (The asteroid that hit the planet 66 million years ago wiped out the dinosaurs because of very bad timing, researchers say.)