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Lift-off for space salvage as junk threatens satellites


Sandra Bullock and George Clooney, brought down to Earth by space junk in the film Gravity

Sandra Bullock and George Clooney, brought down to Earth by space junk in the film Gravity

Sandra Bullock and George Clooney, brought down to Earth by space junk in the film Gravity

As the world's superpowers gear up for a new multi-million euro 'space race', one enterprising Irish boffin hopes to clean up with an engineering solution that is ready for lift-off.

Dr William O'Connor, a lecturer and research engineer at UCD, is competing with some of the world's top scientists in a race against time to design a system to remove thousands of items of 'space junk', such as dead satellites, used rockets and other debris that whizz around in orbit at speeds of up 17,500mph, and which are putting space travel and global telecommunications at risk.

The problem has reached such a critical stage that the congestion of space junk in the Earth's lower orbit means that hundreds of satellites that we rely on for everyday life - enabling GPS on our mobile phones, sat-nav in our cars, weather forecasts, telecommunications and live TV broadcasts - are at risk of colliding with this speeding debris. The rate of collision will increase dramatically as new satellites are launched and dead satellites stay in orbit at the end of their lifespan, posing an ongoing threat to future spacecraft.

Dr William O'Connor, who has worked with the European Space Agency on a number of projects in recent years, says the problem is reaching a critical point - and it's not just a concern of scientists but will affect everyone, including businesses, if nothing is done.

Dr O'Connor, who has submitted a €250,000 tender to the European Space Agency for an innovative solution to remove dangerous space junk, has a successful track record in developing new technology. He was recently awarded a €250,000 contract to develop a rocket control programme which could be used by the ESA's next generation of spaceships in its future missions to space - including to Mars.

Removing the vast amount of space junk that litters the Earth's lower orbit is a mammoth task, however.

Around 20,000 man-made objects in orbit are currently being monitored from the Earth.

These objects include dead satellites that can weigh up to eight tonnes, the upper stages of rockets, and debris such as satellite parts, solar panels, and pieces of metal left behind after explosions and collisions.

Some 10,000 of these objects are fragments created by more than 250 explosions and collisions in orbit. In fact, only about 7pc of monitored objects are fully functioning satellites, according to the European Space Agency.

National space agencies have agreed an annual target to remove 10 objects deemed to be the most imminent threat to functioning satellites or space missions. And now the race is on for European scientists to design a system to start removing them safely.

"The difficulty is that the speed of these objects is up to 30,000 km/h. That's faster than any bullet, so even a small nut or bolt at that speed can do a lot of damage," said Dr O'Connor.

"These out-of-control objects are a menace not just because of their high speeds but also because, if they collide with other objects, they immediately create much more debris, dramatically multiplying the problem."

Indeed, the volume of space junk has grown to such a level that there is a danger we could soon reach a "tipping point" and "create an avalanche of debris in space", warns Dr O'Connor.

Near-misses between space junk and operational satellites are now a common occurrence, the European Space Agency has admitted.

Collision warnings are issued regularly for satellites in polar orbits - where the highest collision risk is found.

About 10 objects a week come within two kilometres of colliding with at-risk satellites - considered a near-miss by space experts - and there are approximately three collision avoidance manoeuvres every year, ESA confirmed.

In scenes reminiscent of last year's Oscar-winning movie Gravity, the six-person crew on the International Space Station had to scramble and take evasive action in a real-life incident when a piece of debris came hurtling towards them in 2012. The space junk came from the 2009 collision of Motorola's Iridium communications satellite - which provided vital phone and data coverage to satellite phones - and a Russian satellite.

This single collision created 2,000 new items of space debris, all of which in turn now have to be tracked.

ESA's environmental monitoring satellite Envisat also suffered a near-miss in 2010 when it narrowly avoided a collision, by just 50 metres, with a piece of speeding debris.

After this incident, European taxpayers began to sit up and take notice as they weren't too happy to hear that a satellite like Envisat, which cost an eye-popping €2.3bn to develop, launch and operate, was nearly shredded by a tiny piece of space rubbish.

The issue of space junk is now firmly on the international agenda.

While there is agreement among all national space agencies that something has to be done about the problem, there is not yet agreement on the best solution, however.

Dr O'Connor is hoping his idea to solve the problem wins approval from the ESA and gets lift-off with a €250,000 research grant.

"Something has to be done about this problem of space debris," he said.

"In our tender to ESA we have proposed a solution and the outline of a mission scenario to deal with debris. Of course the best space companies and researchers from around Europe will also have tendered, and ESA will decide which proposal to support."

Dr O'Connor's solution is first to "de-tumble" an out-of-control satellite and then to return it to Earth by a controlled re-entry over unpopulated areas.

"If a satellite dies all the control systems die as well, and it starts drifting and tumbling unpredictably," said Dr O'Connor. "But from Earth it's very hard to work out exactly what wobbling, turning motion it has. So if you're going to launch a rescue mission and you arrive up there and it's tumbling in a way you didn't expect you've a problem. My proposal looks at how to stop it tumbling with a view to starting a process to bring it back down to earth in a safe, controlled way, without creating more debris.

"We propose using a space craft with a tethered net to capture and de-orbit the objects.

"There are different possible scenarios under study, such as trying to grab the debris with a robotic arm or firing a harpoon to capture it.

"But using a net and elastic tether seems the simplest, lightest and safest option to us, like having a lively fish in a net before you try to control it," he said.

While Dr O'Connor is keeping his feet firmly on the ground by playing down speculation over the ESA tender, there is no doubt that if the plan gets the go-ahead, it opens up the possibility of lucrative, follow-on, space salvage contracts.

It may be a small step for one man, but it would represent a giant leap for Ireland's burgeoning space industry.

Sunday Indo Business