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US Air Force installs remote-controlled telescope in Western Australia to monitor space junk

There are more than 20,000 man-made objects orbiting Earth.

To keep a close eye on them, members of the United States Air Force Academy (USAFA) have installed a telescope at Gingin, 80 kilometres north of Perth. 

The half-metre telescope at the Gravity Discovery Centre Observatory is part of a network of 12 telescopes the USAFA has around the world.

The Falcon Network, when complete, will give it complete oversight of all the objects larger than 10 centimetres in Earth's orbit. 

PHOTO: Professor Francis Chun installed the telescope in a small domed observatory at the Gingin site. (ABC Radio Perth: Emma Wynne)

"The US maintains a space catalogue of about 20,000-plus objects, and out of those, roughly around 1,200 are working satellites," Professor Francis Chun from the USAFA Department of Physics said.

"[But] something has to put the satellites in orbit and it's the rockets. 

"The upper part of the rocket remains in place in orbit around the Earth, so there are a lot of rocket bodies in orbit.

"So the majority of these 20,000 objects are space debris and rocket bodies."

It's crowded up there

Once an object is sent into space, it is there essentially forever unless it is in a lower orbit and burns up in the atmosphere. 

As a result, it is now quite crowded in the geosynchronous orbit — the level at which objects orbit Earth every 24 hours. 

PHOTO: The 50cm Falcon telescope will allow scientists at the US Air Force Academy to monitor space debris. (ABC Radio Perth: Emma Wynne)

Professor Chun said it was only going to get worse, despite agreements to deal with satellites once they become obsolete. 

"There are regulations and policies for any space-faring nation to have end-of-lifetime operations," he said.

"For instance, any low Earth-orbiting satellites have to be able to decay within 25 years. 

"For deep space or geosynchronous satellites, they have to be boosted at the end of their lifetime to a graveyard orbit, which is typically about 300 kilometres above the geosynchronous orbit."

When satellites collide

But despite these agreements, accidents happen. 

"In 2009 there was an accidental collision between a Russian Kosmos satellite and a working Iridium satellite which created a lot of debris," Professor Chun said.

It was estimated that the collision — which occurred at 42,120 kilometres per hour — created more than 2,000 pieces of smaller debris.

In 2011, the International Space Station had to take action to steer clear of debris from that collision.

There was also the potential for more deliberate damage.

"The Chinese demonstrated their anti-satellite weapon capability back in 2007 when they knocked down one of their satellites and created a lot of debris as well," Professor Chun said.

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He said it was in the United States' best interests to take a leading role in monitoring what was going on in space.

"The United States and the rest of the world, both military and civil agencies, rely so much on space — for GPS, weather, communications," the professor said.

"If we didn't have satellite communications it would be extremely expensive even to have internet capability in Australia. 

"We rely heavily as a society on space assets."

Telescope remotely operated from the US

The Gingin telescope, which is considered relatively small in astronomy circles, has been installed in a purpose-built structure with a domed, retractable roof.

It is capable of being remotely controlled; scientists at USAFA will be able to open the roof from their campus in Colorado and see what they need to see.

And although they won't be gazing at the wonders of the cosmos, the images of broken bits of rocket still inspire awe. 

"It always amazes me that with a very modest-sized telescope, half a metre in size, that you can still see a 10-centimetre cube in space over 1,000 kilometres away, just by the light that is reflected off it from the sun," Professor Chun said.