A UK-led experiment to tackle space junk is set to head into orbit. It takes the form of a small satellite that will practise techniques for tracking debris and capturing it. The RemoveDebris system is going to the International Space Station where astronauts are expected to set the experiment running in late May.
Space junk is an ever-growing problem with more than 7,500 tonnes of redundant hardware now thought to be circling the Earth.
Ranging from old rocket bodies and defunct spacecraft through to screws and even flecks of paint – this material poses a collision hazard to operational missions.
RemoveDebris will showcase technologies that could be used to clean up some of this techno-garbage.
The 100kg-class demonstrator is due to ride to orbit on Monday aboard a SpaceX Falcon 9 rocket. Lift-off from Cape Canaveral Air Force Station in Florida, US, is timed for 16:30 local time (21:30 BST.
The satellite will be stored at the ISS for a number of weeks, before being released by the station’s robotic arm to begin a series of manoeuvres. RemoveDebris carries its own "junk" – two small cubesats that it will eject and then track.
For one of these, the "mother" satellite will demonstrate the laser ranging (Lidar) and camera technology needed to monitor and characterise debris in orbit; for the the other cubesat, it will actually try to snare the object with a net.
There will also be a demonstration of a small harpoon. The RemoveDebris satellite will extend a boom with a target on the end. The sharp projectile will be fired at this to learn more about how such devices move and impact a surface in micro-gravity.
At the end of its mission, RemoveDebris will deploy a large membrane. This "sail" will increase the drag from air molecules high in the atmosphere and act to pull the satellite down to Earth much faster than would otherwise be the case.