RemoveDEBRIS satellite captures space junk for the first time

Posted Sep 21, 2018 by Karen Graham
In the video, an experimental cleanup device called RemoveDEBRIS successfully casts a net around a dummy satellite in a stunning demonstration that simulates a technique that could one day capture spaceborne garbage.
The moment the RemoveDebris spacecraft s net captured a space-junk target in a first-of-its-kind tes...
The moment the RemoveDebris spacecraft's net captured a space-junk target in a first-of-its-kind test of debris-cleanup technology. The test occurred in orbit on Sept. 16, 2018.
Surrey Nanosats
The demonstration which occurred Sunday, September 16, is part of the European RemoveDebris mission, designed to test active debris-removal techniques in space for the first time.
The target wasn't an actual piece of space junk but a small CubeSat measuring (10 x10 x 20 centimeters, or 4 x 4 x 8 inches) that was released by the main RemoveDebris spacecraft shortly before the capture experiment, according to
"It went very well," said RemoveDebris mission principal investigator Guglielmo Aglietti, director of the Surrey Space Centre at the University of Surrey in the United Kingdom. "The net deployed nicely, and so did the structure attached to the CubeSat. We are now downloading the data, which will take a few weeks since we only can do that when we have contact with the satellite. But so far, everything looks great."
The RemoveDEBRIS mission is being led by the Surrey Space Centre, while Astroscale assembled the washing-machine-sized RemoveDebris spacecraft, called the ELSA-d chaser satellite, using avionics provided by Surrey Satellite Technology Ltd (SSTL), part of the Airbus Group.
The experiment
Initially, the experiment called for the SpaceDEBRIS spacecraft to release a small "target" satellite into space and then use a net to recapture it. For the test, however, the dummy satellite and net were left to orbit freely. So it essentially created another piece of uncontrolled debris.
Aglietti says the experiment was conducted at a very low orbit and the dummy satellite should fall out of orbit in a few months, plunging to its death. And there is a reason why a real piece of space junk couldn't be used.
Aglietti told that international laws consider even defunct satellites to be the property of the entity that launched them. So this means it would be illegal to catch other people's space junk.
Ingo Retat, who led the team at European space manufacturer Airbus, which designed the net, said it took six years of testing to get the parameters of the net's parabolic arcs just right. "Our small team of engineers and technicians have done an amazing job moving us one step closer to clearing up low Earth orbit," Retat said in a statement.
The net is made of ultra-lightweight polyethylene Dyneema, commonly used to make mountaineering ropes. Six weights attached to the net ensured that it would spread to its full size of 5 m (16 feet) across, said Retat.
"The weights are actually small motors that are used to close the net around the debris," Retat said. "They run on a timer that begins counting down once the net has been deployed, and [they] automatically tighten up to trap the object."
Space debris is becoming an international problem
The world is currently tracking about 18,000 objects orbiting the Earth, but only 1,100 are functioning spacecraft. Additionally, there are an estimated 750,000 more pieces of debris floating around, any of which could cause serious damage to a manned spacecraft.
There are an estimated 170 million pieces of so-called "space junk" -- left behind after m...
There are an estimated 170 million pieces of so-called "space junk" -- left behind after missions that can be as big as spent rocket stages or as small as paint flakesĀ -- in orbit alongside some US$700 billion of space infrastructure
Handout, NASA/AFP
"The experiment is important as there are thousands of pieces of space debris circulating the planet, many traveling faster than a speeding bullet, posing a risk to valuable satellites and even the International Space Station itself," said a UK Space Agency spokesperson in June when the RemoveDEBRIS spacecraft was deployed from the ISS.
There is still the problem of finding the funding to begin removal of space debris. The RemoveDEBRIS experiment cost roughly 15 million euros, or $18 million, and it was jointly funded by the European Commission and the groups involved in the project.
But Jonathan McDowell, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics, says that's relatively cheap as far as space travel goes. But he pointed out that it will take more than one satellite to make a significant impact.
"You can't just have like one garbage truck going around and picking up each [piece of debris]. To change from one orbit to another requires just as much rocket fuel as getting up there in the first place, so it's tricky to find a solution that is cost-effective," McDowell said.