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Space junk cleaning device launched for demonstration

The two spacecraft will play a game of orbital cat and mouseImage source, ASTROSCALE
Image caption,

The two spacecraft will play a game of 'cat and mouse'

A world-first mission to show how technology could be used to help clean up space junk blasts off on 20 March.

The European Space Agency (ESA) estimates that there are around 9,200 tonnes of space junk floating above Earth which could cause a lot of problems.

The End-of-Life Services by Astroscale demonstration (ELSA-d) will launch from Kazakhstan on Saturday but be controlled from a UK base in Oxfordshire.

The UK government has funded the centre because it wants to make Britain a hub for businesses that can service and/or remove ageing satellites.

How much junk is in space and why is it a problem?

Image source, Getty Images
Image caption,

An artist's idea of what space junk might look like

Space junk is debris that comes in all sorts of different shapes and sizes. It could be bits of an old rocket, a broken satellite or a camera, or a screwdriver dropped by an astronaut!

Since 1957 rocket launches have added around 10,680 satellites to the Earth's orbit, and of these around 6,250 are still in space, but only 3,700 are still working.

Space junk can cause problems for astronauts living and working in space, like on the International Space Station (ISS) as it can travel at speeds of more than 17,500 mph as it orbits the Earth, which could cause some serious damage if it hit the spacecraft.

As well as this, space junk can also cause problems for us here on Earth, as it could damage the satellites we use in space for things like maps, mobile phones and the internet.

How does the removal system work?

Image source, ASTROSCALE
Image caption,

The servicer spacecraft

Two bits of kit are involved in the mission, there is a big 175kg "servicer" which has been designed to capture and safely remove space junk, and a smaller 17kg "client", which has been designed to look and act like a piece of space junk for the test.

The servicer will chase down the client, latching on to it using a magnets, before releasing it to try again. It is designed to show how space junk removal could work in different situations including when the junk is tumbling.

After the demonstration both parts are designed to come out of orbit and burn up in the Earth's atmosphere so they don't end up becoming space junket themselves.

Amanda Solloway, the UK science minister, said: "The removal of hazardous space debris is not only environmentally important but is also a huge commercial opportunity for the UK, with companies like Astroscale leading the way in demonstrating how we can make space safer for everyone."

John Auburn, the managing director of Astroscale UK said: "Our team is very proud to have developed the mission control and ground systems for ELSA-d.

"We will perform complex manoeuvres to demonstrate the release and capture of this debris, with the first semi-autonomous robotic magnetic capture of a piece of debris, tumbling through space, using advanced software and autonomous control technology."

If the mission is successful, the scientists are hopeful it will encourage more space clean-up missions in the future.