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CubeSat innovation will help reduce space junk

Paul Sutherland, Feature writer
Nov 26, 2012, 0:00 UTC

Sen—UK rocket scientists have come up with a novel solution to tackle the growing problem of space junk cluttering up the orbital space lanes.

It cannot do much about the flotsam and jetsam that is already littering the skies. But it will help clear orbits of the growingly popular CubeSats that are being launched on missions.

Millions of chunks of junk are whirling around the Earth. They range from defunct satellites and rocket boosters to tiny fragments of debris from a satellite collision and a Chinese weapons test. When the objects collide they can produce even more fragments.

Keeping track of this debris has become a major operation for space authorities, both to protect working satellites from harm and to guard the lives of astronauts aboard the International Space Station. There have been several alerts where crews have had to prepare to evacuate or the ISS has been moved to avoid debris that was seen as a potential threat.

The danger is that the fragments, though often tiny, are travelling at speeds of several kilometres a second and so could puncture the orbital outpost like a bullet with possibly severe consequences for the astronauts aboard.

Now scientists at the University of Glasgow, working with local spacecraft systems manufacturers Clyde Space, have designed new technology to bring smaller satellites out of orbit to burn up in the atmosphere at the end of their useful lives so that they do not add to the amount of defunct space traffic.

Dr Patrick Harkness of the University's School of Engineering has led development of the Aerodynamic End Of Life Deorbit System (AEOLDOS). It will be offered for CubeSats built by Clyde Space for its international customers.

AEOLDOS is a thin membrane supported by struts that stays folded away during the CubeSat's working life. But after that it can be opened, rather like an umbrella, to act as an aerobrake that generates aerodynamic drag in the extremely thin atmosphere that still exists in near-Earth space.

Debris in low-Earth orbit
A plot of the debris that is littering low-Earth orbit. Credit: ESA

CubeSats, which are generally sent into space as secondary payloads alongside bigger satellites, tend to be placed into very low orbits to help ensure they will re-enter the atmosphere within 25 years, as officially recommended. By carrying the new aerobrake, it will be possible to use higher orbits and allow a greater range of experiments to be carried out.

Dr Harkness said: "It's only been 55 years since Sputnik, the first man-made satellite, was sent into orbit, but since then we've managed to make quite a mess of the space around our planet.

"The rate at which we're putting objects into orbit is accelerating each year, which is why it's vital for us to take more control over how they can be removed from orbit once they have served their purpose."

Malcolm McRobb, who helped develop AEOLDOS at the School of Engineering, believes that it has applications beyond space debris control.

He said: "The technology could be used to enable solar sailing missions, where spacecraft can manoeuvre using the pressure of sunlight. Or it could form the basis of deployable antennae, increasing the sensitivity of small, low-powered spacecraft.

"We expect that another year to 18 months of development will see the AEOLDOS system available for commercial use through our licensing agreement with Clyde Space. After we have demonstrated that the technology can work in space, we are looking forward to designing these new and exciting applications for the device."