Space 'harpoon' could corral space junk

A space "harpoon" could grab hold of space debris such as a rogue or redundant satellite and pull it back to Earth, say the British developers of such a system. It is one of a number of proposed solutions to the growing problem of orbiting space junk -- bits and pieces of hardware circling Earth -- that represents a collision threat to operational spacecraft such as satellites and the International Space Station, the BBC reported Tuesday. The harpoon would be fired at an errant satellite or other portion of space debris from close range, and then a propulsion pack tethered to the projectile would pull the junk downward to burn up in the atmosphere, its designer said. "Space has become a critical part of our infrastructure -- from weather forecasting and Earth observation, to GPS and telecommunications," Jaime Reed from Astrium UK said. "Space junk poses a real threat to these vital services if we do nothing about it, and so it's very important we develop capture technologies to remove some of this material. Studies have shown that taking out just a few large items each year can help us get on top of the problem." Reed has proposed a barbed spear about 12 inches in length, mounted on a "chaser satellite" that would approach to within 20 yards of a targeted piece of space junk. Once the harpoon is fired into the skin of the space debris, the chaser satellite could either pull on a trailing cord to affect the orbit of the debris or deploy a separate thruster unit to drag the wandering object back toward Earth, he said.