US Space Fence plants first post – on a Pacific island

The first radar post for the US Air Force's 'Space Fence' surveillance system will be built on Kwajalein Island in the Marshall Islands, military authorities have announced.

The Space Fence is designed to track thousands of space objects, including satellites and man-made debris, in low and medium Earth orbits. Construction on Kwajalein Island is expected to begin in 2013, with the station coming online in 2017, the US Air Force (USAF) said in a statement on Wednesday.

According to USAF, the Space Fence radar system will operate in the S-Band frequency and will be capable of detecting a softball-sized object from 1,200 miles away. When finished, it will "provide evidence of satellite break-ups, collisions or unexpected manoeuvres of satellites", the USAF said.

Air Force Space Command is yet to award a contract to build the radar. Lockheed Martin and Raytheon are both working on technology for the Space Fence, which has a price tag of $3.5bn and will reportedly be able to track some 200,000 objects in orbit. According to the USAF, around 95 percent of space objects are debris.

Air Force Space Command supports the US military worldwide through its use of satellite and space technology. It celebrated its 30th anniversary this month, having opened on 1 September, 1982.