
Image generated by NASA shows approx. 95% of the objects in orbit around the earth. Photo courtesy of NASA (http://orbitaldebris.jsc.nasa.gov/photogallery/beehives.html)
The United States Air Force recently announced the first location for its upcoming Space Fence radar system: Kwajalein Island. The announcement comes as defense contractors Raytheon and Lockheed Martin work towards completing the second phase of the contract that began in February, 2011. Both companies have demonstrated prototypes for the Air Force and are awaiting a Request for Proposal, or RFP, to be released in order for one of their designs to be implemented. The initial contract was awarded in June 2009 to Raytheon, Lockheed, and Northrop Grumman who was cut in the second phase.
The Space Fence program while serve to replace the Air Force’s aging Space Surveillance System currently in use. The existing system, developed in the early 1960’s, consists of three transmitter sites and six receiver sites with the purpose of tracking space objects passing over the United States. The system operates in the VHF frequency range and can detect objects as small as 4 inches in length.
On 10 February, 2009, Iridium-33 and the Russian Kosmos-2251 satellites hurtling around the planet, unresponsive to commands, collided over SIberia. The result of this accidental crash was a cloud of thousands of pieces of debris a various shapes and sizes. These pieces join the debris already in place from decades of launching objects into space as well as the debris cloud created from the Chinese anti-satellite (ASAT) test in which they launched a ground-based missile at their own inoperative weather satellite in January, 2007. The increasing amount of debris made it clear to the Air Force they needed the ability to have a better view of the objects in orbit. In a story written by Fox news NASA stated in 2011 over 22,000 individual objects were being tracked. The key issue is most of the uncontrollable debris is in orbit is at the same altitudes as operational assets, to include the International Space Station. Periodically, collision avoidance maneuvers are required to be performed by the ISS, as well as other satellites, to prevent one of these objects inflicting a fatal wound.
The new Space Fence is based on S-band frequencies, allowing smaller objects to be seen due to its shorter wavelength. In addition, the stations will not be confined within the United States, but will be installed in specific worldwide locations in such a manner as to provide a global awareness. These locations would be controlled by the Joint Space Operations Center at Vandenberg AFB, located in Lompoc, CA. The Space Fence will cover low earth orbits as well as medium earth orbits as its primary missions. Regarding debris in the geostationary orbit, NASA states that most operators will push a satellite nearing the end of its life out beyond the orbit into what they term a “disposal orbit.”
The Kwajalein Atoll is the largest island that comprises the Republic of the Marshall Islands. The remote island, located roughly 2100 miles southeast of Hawai’i, has provided support to the U.S. military beginning in 1944. The control center for the nuclear tests at the Bikini and Enewetak atolls was located at Kwajalein.
Below is a video created by Lockheed Martin outlining their concept of the Space Fence.
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