Is it possible to remove the space junk having orbital velocity with the help of a skyhook?
Has any country in the world planned to place a skyhook in orbit?
There is the ElectroDynamic Debris Eliminator (EDDE) notion that seems to be pretty serious. Not clear if they have realistic funding or not.
This is basically a multisegmented tether that using solar panels along its length for energy generation, rotates and grabs debris in a net at the end to then deorbit.
A key design feature is that if it gets severed the remaining elements can continue to operate as two smaller EDDE vehicles.
Astrium is working on a space harpoon capture system. They have been awarded a study contract by the French space agency CNES to develop space vehicles that can remove large items of debris from Earth's orbit. Their idea is to develop a pneumatic space harpoon that a spacecraft would fire into larger space debris targets and use tether to drag them out of orbit and into the atmosphere:
The harpoon design is trying to minimize secondary debris from puncturing the target's body. It has a set of barbs, a shock absorber section that is the wide part in the photograph above and releases the barbs into open, hook-like position after impact, and a shaft that is inserted into the pneumatic gun that holds the tether with which the target is later towed by into the atmosphere.
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