NASA currently monitors approximately 17,000 pieces of space junk that are orbiting the earth at extremely high speeds. These odds and ends consist of things like dead satellites, spent rocket stages and parts that have broken off of spacecraft. As the amount of junk increases, it becomes increasingly difficult for functioning satellites to avoid colliding with it. When collisions do occur, the satellite is often destroyed, with the resulting debris further adding to the problem. Scientists from Swiss research institute EPFL, however, have decided that enough is enough - they're currently developing a small satellite known as CleanSpace One, which will be tasked with grappling expired satellites and pulling them back to Earth.
The first CleanSpace One prototype will, appropriately enough, be sent after one of two non-functioning Swiss satellites - the Swisscube picosatellite, or its cousin, the TIsat.
Once launched, CleanSpace One will have to match the target satellite's orbital plane of 630-750 kilometers (391-466 miles) above sea level. In order to do so, it will have to adjust its trajectory, using an ultra-compact motor that is still in development at EPFL.
Next, once it's within range of its quarry, it will have to grasp and stabilize it. This should prove challenging, as the dead satellite will be moving at 28,000 km/h (17,398 mph), and could be rotating. An appropriate gripping mechanism will need to be created, which EPFL states will be "inspired from a plant or animal example."
Finally, once CleanSpace One has captured its target, the two of them will head out of orbit and towards the earth, where they will both burn up in the atmosphere. So yes, the prototype will be going on a suicide mission, but a whole line of CleanSpace-inspired satellites are planned for the future, each one capable of capturing and destroying a different type of satellite.
The orbital rendezvous of CleanSpace One and one of the two picosatellites could be taking place within three to five years, depending on funding and availability of industrial partners.
More information is available in the video below.
Source: EPFL via Popular Science