After over fifty years of operation, the United States Air Force has de-activated its Space Fence space debris surveillance system.
Correctly referred to as the Air Force Space Surveillance System (AF3S), the decision to close down Space Fence has been controversial as it will be some time until a replacement system is operational. The new AF3S is tipped to commence work in circa 2017. This has led to concerns that military and civilian spacecraft operators may be bereft of information regarding possible threats to their satellites from orbiting space debris.
Both Lockheed Martin and Raytheon are competing to construct the new Space Fence. This will use S-band radars to track up to 200,000 targets, including those as small as a tennis ball in size, at a range of up to 1,930 kilometres (1,042 nautical miles).
The value of the new Space Fence system contract is estimated at €3 billion ($4 billion). On 28th September 2012 the USAF revealed that the first radar will be constructed on KwajaleinIsland, part of the Republic of the Marshall Islands in the Pacific Ocean. Radar imagery from the Space Fence will be relayed to the United States Strategic Command’s Joint Function Component Command for Space at Vandenburg Air Force Base, California.