Asteroid hunters want to launch private telescope

Who will protect us from a killer asteroid? A team of former astronauts and scientists for the US space agency thinks it\'s up to them. In a bold plan unveiled Thursday, the group of former Nasa employees wants to launch its own space telescope to spot and track small and mid-sized space rocks capable of wiping out a city or continent. They could sound early warnings if a rogue asteroid appeared headed toward our planet. So far, the idea from the B612 Foundation is on paper only. Such an effort would cost upward of several hundred million dollars. Behind the nonprofit foundation are a space shuttle astronaut, Apollo 9 astronaut, former Mars czar, deep space mission manager and other non-Nasa types. Asteroids are leftovers from the formation of the solar system some 4.5 billion years ago. Most reside in the asteroid belt between Mars and Jupiter, but some get nudged into Earth\'s neighbourhood. Nasa and a network of astronomers routinely scan the skies for these objects. They\'ve found 90 per cent of the biggest threats — asteroids that are considered major killers. Scientists believe one such asteroid wiped out the dinosaurs. But the group thinks more attention should be paid to the estimated half a million smaller asteroids — similar in size to the one that exploded over Siberia in 1908 and levelled more than 2,000 square kilometres of forest. \"We know these objects are out there, and we can do something to prevent them\" from hitting Earth, said former Apollo 9 astronaut Rusty Schweickart, who helped establish the foundation a decade ago. Under the proposal, the asteroid-hunting Sentinel Space Telescope will operate for at least 5 1/2 years. It will orbit around the sun, near the orbit of Venus. Data will be beamed back through Nasa\'s antenna network under a deal with the space agency. Launch is targeted for 2017 or 2018. The group is angling to fly aboard SpaceX\'s Falcon 9 rocket, which made history last month by lifting a cargo capsule to the International Space Station.