Gravity: Japan to test ‘magnetic net’ that can fish out floating space junk

January 18, 2014 – SPACE – The Japan Aerospace Exploration Agency (Jaxa) is teaming up with a company that manufactures fishing equipment to create a net that will sweep the heavens of the man-made debris orbiting our planet. The first test of the equipment is scheduled to start in late February, when a rocket will be launched and a satellite developed by researchers at Kagawa University will be deployed. Once in orbit, the satellite is designed to unreel a wire net some 300 metres long that will then generate a magnetic field and – theoretically – attract some of the debris that is circulating beyond our atmosphere. And there is a growing need for outer space to undergo a good clean-up, with experts estimating that 100 million bits of man-made junk zipping around the earth. Of that total, some 22,000 are believed to measure 10 cm or larger and are therefore considered dangerous. The majority of the debris is in a band between 700 kilometers and 1,000 kilometers above the surface of the planet, mostly parts of obsolescent and degrading satellites and rockets. Out of control and impossible to accurately monitor, even the smallest piece of detritus – a single bolt, for example – could have a catastrophic result if it collides with a functioning satellite or the International Space Station, which has a permanent human crew aboard. A recent study in the U.S. suggested that a collision between two satellites could trigger an “uncontrolled chain reaction” that could destroy the communications network on earth.

“We started work on this project about five years ago and we are all excited to see the outcome of this first test,” Koji Ozaki, the engineer who heads the development team at Hiroshima-based Nitto Seimo, told the South China Morning Post. The net is a mere 30cm wide when it is unspooled and made of three strong and very flexible lengths of metal fiber, Ozaki said. Taking advantage of the company’s experience in the fishing industry, a net measuring 1 kilometer long has already been fabricated at Nitto Seimo’s factory. “Fishing nets need to be extremely strong because they need to be able to hold a large number of fish, but our tether does not have to be that strong,” he said. “It is more important that it is flexible.” Reports first emerged about the project three years ago, but there were no confirmations about it being tested. The upcoming test is designed to confirm that when a magnetic field is passed through the net, it is able to attract pieces of orbiting debris. Gradually, over the space of about one year, the net and the junk that it has collected will descend closer to Earth and burn up in the frictional heat generated when it reaches the atmosphere. In the future, Jaxa plans to use space craft to attach nets to larger pieces of space junk – rocket engines or satellites that are no longer operational – and let gravity and the atmosphere complete the task of eradicating the threat. Jaxa is planning further trials next year and a functioning system could be deployed as early as 2019. –SCMP