One of the latest looks at the orbital debris quandary was completed by the Defense Advanced Research Projects Agency (DARPA).
Released with little fanfare a few months ago, it was dubbed “The Catcher’s Mitt Study” – to assess the debris problem and its future growth, determine where the greatest problem will be for U.S. assets and then, if appropriate, explore technically and economically feasible solutions for debris removal.
A central finding of the study is that the development of debris removal solutions should concentrate on pre-emptive removal of large debris in both low-Earth orbit (LEO) a few hundred miles above the planet, as well as geosynchronous Earth orbit (GEO), the realm of communications satellites and other key spacecraft about 22,400 miles (36,000 kilometers) up.
Phantom Report: DARPA budget [PDF] is 522 pages, one area of research that was interesting was dubbed ‘Machine Intelligence’. Related: 2011 DOD president’s Budget: DARPA