The Defense Advanced Research Projects Agency (DARPA) announced Tuesday that it plans to offer robotic, in-orbit satellite servicing starting in 2015, which would recycle old satellites to provide greater communication capabilities to warfighters from 22,000 miles above the earth.

Defunct communication satellites are being scavenged for their valuable parts and recycled to reduce the cost of building new ones in the latest pet project from the Pentagon's research wing.

When satellites retire, certain parts such as antennas and solar panels often still work - but there is currently no routine effort to salvage and reuse satellite parts once they are launched into space.

"Phoenix uses its modest effort to increase the return-on-investment for DoD space missions," Dave Barnhart, a DARPA program manager, said at a press conference.

Using robotic arms and cameras, some of which will be controlled using DoD software from earth, DARPA believes it can fix up the defunct satellites, of which there are about 140 that are good for 'harvesting'. The four-year program has been allocated $180 million to launch the mission.

As a result of the mission, the government will save millions of dollars on antennas and solar panels, which often still work when a satellite retires but cannot easily be retrieved. Recycling the satellites will be expensive at first, but will save money in the long run.

The biggest challenge that DARPA will face is putting together the new system without breaking the antenna from the retired satellite.