Laser system tracks space junk

Australian researchers say they are developing a laser tracking system that could prevent expensive collisions between space junk and spacecraft or satellites in the Earth's orbit.

Electro Optic Systems says it would be the world's first automated, high-precision, laser trackingsystem, which could replace existing radar networks.

Craig Smith, CEO of the Canberra-based aerospace company, says existing tracking systems cannot determine orbits in space with enough accuracy to prevent collisions.

Smith says laser beams fired from the ground in Canberra could protect astronauts and satellites by targeting potentially damaging debris as small as 10 centimetres across.

Science has left a trail of rubbish duringthe exploration of space. It's estimated that around a half-million chunks of debris measuring a centimetre across or larger are littering the Earth's orbit. Another 200,000 objects measuring less than that size are floating around in that part of space.

Some satellites have been hit by fast-moving pieces of junk, resulting in explosions if they have any fuel left in them.

The remains of old rockets can be the size of a bus, while other fragments are no larger thantiny flecks of paint.

"They are all hurtling around in space at 36,000 km/h, and so even a one-millimetre piece of space junk can destroy or damage a satellite," Smith said.

Data collected from the Mount Stromlo observatory in Canberra could be sold to satellite owners and agencies like NASA, allowing them to move equipment out of the way of an incoming chunk of debris.

The company has received $3.6 million from the Australian government to develop the new tracking technology.

Smith says the company hopes to demonstrate the system in 2010.