Self-destructing satellites designed to reduce space junk

The European Space Agency is re-designing satellites so that they can self-destruct in space.

As part of the Clean Space Programme, the ESA is working to make satellites ‘D4D’ – designed for demise.

500,000 pieces of debris

There are currently more than 500,000 pieces of debris orbiting the Earth, NASA says. It adds that this “pollution” means that space missions will have to avoid certain orbits.

Stijn Lemmens, Space Debris Analyst at ESA says: “There are regions near Earth where there are so many debris fragments that the operation of spacecraft would no longer be an option.”

Lemmens says that new regulations are being put in place to clean up the Earth’s orbit, which will force satellites to re-enter the Earth’s atmosphere.

Redesigning how satellites function

He says: “The grand hope is of course a spacecraft that poses zero risk to people and structures on the ground.”

The D4D initiative is looking at redesigning satellites to change how they function.

Tiago Soares, a system engineer at ESA, says one design would mean “the outside panels of a satellite would open like petals from a flower before re-entry”.

Another idea is to “use joints that will easily melt to break up the structure earlier during the atmospheric re-entry”.

Testing new materials

Parts of satellites that are made out of materials with high melting points, such as titanium and stainless steel, can survive re-entering the atmosphere and end up landing on Earth.

The D4D initiative is currently testing materials like aluminium alloys to see if they are more likely to destruct before reaching earth. Materials are being tested virtually, using software, and physically, by blasting hypersonic air jets and heat at them in wind tunnels.

The ESA will be implementing a programme called CleanSat to have designs like D4D ready for the re-entry stage of the space agency’s upcoming missions.

© ESA