The projectile, measuring a meter long, would be attached to a strong tether and would chase spacecraft to get them out of the sky, the BBC reports. Ideally, once the target is successfully snagged, the chasing vehicle would then drag the debris down to let it burn in the atmosphere.
The aerospace company has been working on this concept for a long time now, coming up with even bigger systems as a response to the increasing problem of orbital junk – pieces of old hardware that continue to just float around the planet, posing a collision threat to functional satellites.
Around 20,000 items larger than 10 centimeters are being tracked for disposal. This latest Airbus harpoon is being developed with the aim of capturing one of the biggest items of the lot: the defunct Envisat Earth observation platform from Europe. The gigantic spacecraft, weighing eight tons, died in orbit in 2012.
Alastair Wayman, advanced project engineer, said,
Envisat is the outlier. If we can design a harpoon that can cope with Envisat, then it should be able to cope with all other types of spacecraft including the many rocket upper-stages that remain in orbit.
Airbus’s testing facility in Stevenage, the United Kingdom, sees the harpoon getting launched using compressed air into a panel constructed similarly to satellite structures. These are generally thick, composite honeycomb panels made up of a lot of aluminum. Wayman said, “The harpoon goes through these panels like a hot knife through butter. Once the tip is inside, it has a set of barbs that open up and stop the harpoon from coming back out. We’d then de-tumble the satellite with a tether on the other end.”
Harpoons are simple, yet very effective devices compared to robotic arms or nets. Wayman explained, “Many of these targets will be tumbling and if you were to use a robotic arm, say, that involves a lot of quite complex motions to follow your target. Whereas, with the harpoon, all you have to do is sit a distance away, wait for the target to rotate underneath you, and at the right moment fire your harpoon. And because it’s a really quick event, it takes out a lot of the complexity.”