Space junk-zapping lasers under development

It may sound like science fiction but an Australian team is working on a project to zap orbital debris with lasers from Earth to reduce the growing amount of space junk that threatens to knock out satellites with a "cascade of collisions".

The project is very realistic and likely to be working in the next 10 years, Matthew Colless, director of Australian National University's Research School of Astronomy and Astrophysics, told Reuters.

"It's important that it's possible on that scale because there's so much space junk up there," he said. "We're perhaps only a couple of decades away from a catastrophic cascade of collisions ... that takes out all the satellites in low orbit."

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Scientists believe there are more than 300,000 pieces of debris — made up of everything from tiny screws and bolts to large parts of rockets — orbiting Earth, mostly in low orbits and moving at tremendous speed.

Laser tracking is 1st step

Australia now has a contract with NASA, the U.S. space agency, to track and map space junk with a telescope equipped with an infrared laser at Mount Stromlo Observatory.

But $20 million from the Australian government and $40 million in private investment will help the team set up as the Cooperative Research Centre (CRC) to develop better lasers to track tiny pieces of debris, importing techniques from astronomy used to remove the blurring of the atmosphere.

The ultimate aim is to increase the power of the lasers to illuminate and zap pieces of junk so they burn up harmlessly as they fall through the upper atmosphere.

"There's no risk of missing and hitting a working satellite," Colless said. "We can target them precisely. We really don't miss."

Colless said he imagines an eventual need for a global network of stations set up under international auspices but, right now, the CRC is doing the research to make it possible.

The CRC is made up of universities, space agencies and companies including Lockheed Martin, Optus and EOS Space System Australia.