Space Junk - We take out the trash

End-of-life satellites and other space junk left in orbit constitute a rapidly growing problem and have attracted great political attention because space junk is a threat to communications and national security. Space junk is a threat to the future use of space because of the danger of collisions between active satellites and disused ones abandoned in space. Researchers from Aalborg University Esbjerg have invented a simple self-expanding construction which will allow them to remove some of this space junk in the future.

The invention consists of a ring-shaped frame, a sail stretched over the frame, a unique folding method, an anchorage to the satellite and a locking mechanism which ensures that the folded sail does not unfold until the satellite mission is over. The invention is based on a basic principle used in pop-up tents, in pop-up frisbees and in the screens which photographers use to control light and shade which can be folded two or three times at most. The unique folding principle means that the frame can be folded as many as seven or nine times, and thus the inventors have created an ultra-compact, simple and energy-neutral solution that can be used as a wind brake for end-of-life satellites in space.

Supported by the Agency for Research and Innovation, in 2011 the inventors cooperated with satellite experts from GomSpace to conduct a proof of concept project, which proved the invention technically suitable as a satellite brake for satellites. In Low Earth Orbit (LEO), up to 1000 km from the Earth, sufficient air resistance exists ensuring that the massive increase in the satellite surface area caused by the brake will slow down the satellite to the extent that it will come out of its orbit and burn up on its way down through the atmosphere instead of ending up as space debris.

The technology has been testet within the framework of AAU through a Proof of Concept project received from The Danish Agency for Science, Technology and Innovation and furthermore evolved by GomSpace in collaboration with AAU for a full scale demonstration in a Danish National Advanced Technology Foundation project. The collaboration also continues in projects like TeSeR (Technology for Self-Removal of Spacecraft), which will help ensure that future spacecraft do not present a collision risk once they reach the end of their operational lifetimes. TeSeR is part of the European Union’s Horizon 2020 research and innovation program.

ADDITIONAL INFORMATION

• Article from AAU Update: Support for space inventions and other AAU projects (in Danish)
• Article from The Engineer (Ingeniøren): Mickey Mouse ears to clean up space junk (in Danish)
• Article from Nordjyske: Northern Jutland firm gets large cash injection (in Danish)
• Article from JydskeVestkysten: Success: Now space will be cleaned (in Danish)
• Article from Videnskab.dk: Danish invention to destroy end-of-life satellites (in Danish)
• Article from Videnskab.dk: Satellite brake will send space junk on the road to destruction (in Danish)
• Read more about the TeSeR project