Space Fence

The Space Fence is a second-generation space surveillance system currently being built by the US Air Force in order to track artificial satellites and space debris in Earth orbit.

Contracts were issued for development and construction in 2014, and the Space Fence is expected to be operational in 2019. The budget is US$1.594 billion (FY15).

The initial space fence facility will be located at Kwajalein Atoll in the Marshall Islands, along with an option for another radar site in Western Australia.

The initial plans to upgrade the legacy Air Force Space Surveillance System were made in 2009. The USAF 850th Electronic Systems Group, Electronic Systems Center awarded three $30-million study contracts to Lockheed Martin, Northrop Grumman and Raytheon on 11 June 2009.

The new Space Fence was envisioned to be a system of two or three S-band ground-based radars designed to perform uncued detection, tracking and accurate measurement of orbiting space objects, and was intended to replace the Air Force Space Surveillance System, or VHF Fence, that was transferred from the US Navy to the US Air Force in 2004. The shorter wavelength of the S-band Space Fence will allow for the detection of much smaller satellites and debris.

The February 10, 2009, collision of a U.S. Iridium communications satellite (Iridium 33) and a Russian Cosmos 2251 communications satellite, which added hundreds more pieces of debris to the atmosphere, highlighted the need for more precise tracking of space objects.

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