Back in the 1970s, there was a short-lived sitcom called Quark about an outer space rubbish collector. What was played for laughs back then may soon be a reality with the announcement that Ecole polytechnique federale de Lausanne (EPFL) and Swiss Space Systems (S3) have formed a partnership to launch the CleanSpace One satellite into orbit to collect space debris using a launch system that promises to be cheaper than using conventional techniques.
There are estimated to be more than 16,000 pieces of space debris orbiting the Earth larger than 10 cm (3.9 in) in diameter. That’s doesn't amount to much in the vastness of space, but satellites tend to cluster in similar orbits and a satellite collision, such as occurred in 2009 between Iridium 33 and Kosmos-2251, could cause this number to increase exponentially. If that happens, it would make space travel much more difficult and expensive.
There are many plans for making satellites less of a hazard to navigation. These approaches include installing microthrusters or solar sails as a way to plunge them back into the atmosphere or into deep space, but that still leaves the question of how to deal with the debris already up there, or which might be created inadvertently despite attempts to mitigate the problem.
One answer is the CleanSpace One satellite. Scheduled to launch in 2018, it’s under development by EPFL with the current version weighing in at a mere 30 kg (66 lb). It uses many off-the-shelf technologies and many key components have been developed with various partners, including the European Space Agency.
Equipped with thrusters, CleanSpace One is designed to rendezvous with a disabled satellite. Once on station, a claw reaches out, clamps on to the debris, and CleanSpace One pushes the debris and itself into the Earth’s atmosphere on a kamikaze dive. For it’s first test, it will rendezvous with a de-commissioned Swiss nanosatellite measuring only 10 cm (3.9 in) wide.
On September 10 EPFL entered into an agreement that made S3 of Payerne, Switzerland, the prime partner in the CleanSpace one project. S3 will invest CHF10 million (US$10.7 million) for the launch and CHF5 million (US$5.3 million) for assembling and testing the satellites and for command operations. S3’s contribution to the project, aside from money, is to provide a cheaper way to get CleanSpace One into orbit. To achieve this, the company has developed a variation on the piggyback method of launching satellites that handles payloads up to 250 kg (551 lb).
The launch system uses the Suborbital Reusable Shuttle (SOAR), a small unmanned shuttle, taken aloft by an A300 jet airliner. At an altitude of about 10 km (33,000 ft), the SOAR is released and flies under its own power to an altitude of 80 km (263,000 ft). There it launches a rocket booster stage that flies to an altitude of 700 km (435 mi), where it releases its payload into orbit.
The advantage of this system is that all the parts, including satellites, have their own re-entry systems, have no need for exotic fuels, and the mission can be aborted up until the booster launch without losing the payload. On the whole, S3 claims that this reduces costs by a factor of four. S3 is taking responsibility for the launch of CleanSpace One as the first payload for the system.
“You can’t democratize space access without having a responsible attitude,” says Pascal Jaussi, CEO of Swiss Space Systems. “If we don’t deal with the problem of orbiting space debris and its accumulation, future generations’ access to space will be compromised.”
The video below outlines the new partnership between EPFL and S3.