An experimental satellite has brought us one step closer to cleaning up our act in space by harpooning a piece of simulated debris in low Earth orbit. The University of Surrey's RemoveDEBRIS technology demonstrator satellite deployed a target panel at the end of a 1.5 m (4.9 ft) boom, then skewered it with a metal harpoon traveling at 20 m/s (44.7 mph, 72 km/h) as part of a series of experiments to test various space debris clean up techniques.
Space may be vast and emptier than our imaginations can grasp, but with over 7,600 tonnes of man-made debris in orbit, our immediate neighborhood is becoming increasingly risky for future missions. Compared to the volume it occupies, this debris doesn't even count as a rounding error, but these dormant satellites, old boosters, paint flecks, and various bits of shrapnel left over from satellite collisions travel at hypersonic speeds in the same orbits as active satellites, so a particle smaller than a grain of sand can cause terrible damage.
Designed, built, and manufactured by a consortium of leading space companies and research institutions led by the University of Surrey and operated by Surrey Satellite Technology with co-funding by the European Commission, the 100-kg (220 lb) RemoveDEBRIS technology demonstrator is looking to address this problem with a series of four experiments for seeking out, capturing and deorbiting hazards to space navigation.
The space harpoon is the third of these experiments. It consists of a launcher, a tethered harpoon, and a flip-out locking mechanism to secure the target on penetration. The previous two experiments were a net launcher for ensnaring satellites and a LiDAR and camera-based vision navigation system to identify space debris. The fourth and final experiment is a sail that will increase orbital drag and cause RemoveDEBRIS to plummet into the Earth's atmosphere, where it will burn up.
"[The harpoon is] RemoveDEBRIS' most demanding experiment and the fact that it was a success is testament to all involved," says Professor Guglielmo Aglietti, Director of the Surrey Space Centre at the University of Surrey. "The RemoveDEBRIS project provides strong evidence of what can be achieved with the power of collaboration – pooling together the experience across industry and the research field to achieve something truly remarkable."
The video below shows the harpoon test in slow motion.
Source: University of Surrey
But is there a chance that the impact from the harpoon would cause the piece of debris to break up further?
And, seriously, for every gram of "space junk", they're going to be adding a kilo of rocket exhaust, which will screw with everything a heap more than the "junk" ever did, and in a vicious feedback loop - the more friction from this, the more all satellites will need to exhaust their own fuel to compensate, making the problem exponentially worse.
They're going to reduce the "life span" of rockets by tenfold, just to reduce the chances of debris damage by a teeny tiny fraction.
Imagine, a large satellite w/ robotic arms & it has a pure electric drive that does not require fuel! It starts w/ largest space junks! Each time, it grabs its target, takes it down low enough so Earth's atmosphere takes the junk down quickly! & it goes after its next target (automatically)!
(To cleanup small junk pieces, it could also have a net and/or bucket.)