On Sunday, the University of Surrey’s Space Center made history when it successfully captured a piece of space junk in orbit. It is the first time an active debris removal system has ever been demonstrated in space.
The test was carried about by the RemoveDEBRIS satellite, an experimental space debris removal platform built by an international consortium of space companies and university research centers. There are tens of thousands of pieces of fast-moving space junk in orbit, which range from the centimeter-scale all the way to entire rocket stages. Some of these pieces are moving faster than a bullet and all of them pose a serious danger to other satellites and crewed capsules.
The RemoveDEBRIS satellite consists of a large, 220-pound main satellite that carries two smaller cubesats and a net. The mission involves deploying these cubesats as artificial space junk and them capturing them to demonstrate the effectiveness debris removal technology. The first cubesat was successfully captured on Sunday evening with a net after six years of testing the technology on Earth.
"We are absolutely delighted with the outcome of the net technology,” Guglielmo Aglietti, the director of the Surrey Space Center, said in a statement. “While it might sound like a simple idea, the complexity of using a net in space to capture a piece of debris took many years of planning, engineering and coordination."
In the video above, you can see the cubesat deploying an experimental drag sail before it is captured by the net. This is a cubesat deorbiting technology that is being developed by the Surrey Space Center, but it also provides a larger target for the net. When the cubesat is about 20 feet away, the main satellite deploys the net which wraps around the cubesat and a motor is used to cinch the net closed.
At this point, the cubesat is then left to deorbit. Due to the drag sail, it will deorbit faster than it was left to its own devices and will burn up when it re-enters the atmosphere.
The next cubesat will be launched from the platform and used to test “vision-based navigation” algorithms, which will use AI and LiDAR systems to monitor the simulated space debris (the cubesat) from ground stations on Earth. The final test on the RemoveDEBRIS mission will involve using a harpoon to capture a small 10x10 cm inflatable target at close range.
These space debris removal technologies will crucial to space access in the future. There are currently over 500,000 pieces of space junk in orbit. This space junk is the detritus of past missions and ranges from small pieces of metal to entire rocket stages. Removing this junk from orbit is particularly challenging because of the various sizes of the debris, its erratic tumbling motion, and the fact that some pieces are moving as fast as 30,000 miles per hour.