NZ to help clean up space junk Space debris could affect plans to launch about 40,000 satellites in the next 10 years.

Max Arshavsky can see a time coming when, if nothing is done, there will be no internet, GPS, satellite TV and "many of the things that make our lives more convenient".

That's because of space debris, what many of us call "space junk". There is so much of it above us, silently and invisibly orbiting the earth, scientists are beginning to worry that the pollution we cannot see from the ground will prevent any more satellites from being launched…globally.

So Arshavsky, who together with University of Auckland students Will Haringa and Sebastian Wieczorek has formed ZENNO Astronautics, are working on two projects – and recently won funding from the university's entrepreneurial fund Velocity* to do so.

They are working on a propulsion system for satellites. If that sounds odd (propulsion systems have existed for some time), it is hugely important for the future.

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Arshavsky says ZENNO are trying to undo a situation caused by decades of "old school" space exploration and satellite placement. Previously, he explains, launching rockets and satellites into space was the province of governments, with massive budgets and equipment – generally, satellites would weigh a few tonnes.

Now, with advanced techniques, satellites are now launched far more frequently by commercial companies. They come in much smaller packages – even a 10cm x 10cm x 10cm cube known as a "CubeSat". Typically, companies needing satellites use up to three or more of these cubes together.

"They are easier to build, easier to launch and easier to replace if one malfunctions," says Arshavsky.

But there is another problem. The old school space philosophy did not include getting rid of the space hardware once it had fulfilled its mission. It would just hurtle round Earth for 100 years or more (and maybe forever) until air drag dismantled it.

But that means there is a huge amount of space debris surrounding the planet – the European Space Agency estimates over 160 million objects over 1mm in diameter. As Arshavsky points out, even a tiny piece of space debris can cause big damage – and even cost lives.

"A little while ago the International Space Station was damaged by a flake of paint that came off one of the rockets launched," he says. "Just a flake of paint – but it was travelling so fast, it dented a window on the space station and nearly penetrated it.

That could have caused loss of life and Arshavsky guesses it might be only "decades" before there is too much congestion in low orbits to get more satellites up without the danger of collision with space debris: "It's like trying to cross busy six-lane motorway by just running straight across.

"If that [congestion] happens – and everyone is now working to make sure it doesn't – there will be no internet, no GPS, no Google map, no Sky TV…all those things we take for granted in our daily lives."

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The world is launching 400 satellites a year already. Over the next 10 years, that is expected to swell to 4000 satellites per year – about 100 a year likely to be from New Zealand's own Rocket Lab (and each rocket can carry dozens of small satellites).

So the agencies have all agreed on a 25-year post-mission limit – in other words, 25 years after completion of the mission the satellite must be removed from orbit, either sending it into space or returning it to Earth.

There's just one problem (and that's where ZENNO come in). With so many small satellites now, it is difficult to fit them with a propulsion system – as they are difficult to scale down to a 10cm cube.

ZENNO are also working on new software designed to make it easier to get the licences needed to launch a satellite – necessary because "old school" red tape can obstruct or delay new-era technology.

They are also working on a space debris mitigation plan for the first of two satellites to be launched by the university – the plan being how to take the satellite out of orbit once it has fulfilled its task.

That task is earthquake detection, with the first satellite (QuakeTec) analysing measuring electron density and other plasma characteristics in the ionosphere to see if precursors to earthquakes can be detected up to five days in advance.

The second satellite (Kessler) is designed to help prove the viability of electrodynamic tethers for commercial purposes. Tethers are a method of de-orbiting satellites and other objects in low orbit round the Earth.

*Velocity is the country's leading student-driven entrepreneurship programme. Since its inception at the University of Auckland in 2003, alumni have launched more than 120 ventures, attracted over $221 million in investment, created 600-plus jobs, and sold products and services into 37 countries.