Lockheed Martin won a $915 million contract Monday to build a "space fence" for the U.S. Air Force to monitor hundreds of thousands of objects in orbit, allowing the military to detect and track ten times more space junk than possible with existing decades-old technology.

A view inside Lockheed Martin's prototype Space Fence control center. Credit: Lockheed Martin
 
The contract award announced Monday on a Defense Department website comes after a competition that pitted proposals from Lockheed Martin and Raytheon against each other to build the Space Fence, which the Air Force says will modernize the way it scans the sky for space junk.

The military's Joint Space Operations Center, or JSpOC, is in charge of tracking space traffic and issuing collision threat notices to global satellite operators, which can move their spacecraft out of the way if notified in time.

The deal with Lockheed Martin Mission Systems and Training covers the construction of an S-band Space Fence radar facility at Kwajalein Atoll in the Marshall Islands, plus an option for another radar site in Western Australia. The total value of the contract, including options and incentives, is estimated to be nearly $2 billion.

Completion of the Kwajalein radar site is scheduled for 2018.

Lockheed Martin and Raytheon received Air Force funding starting in 2009 to pay for design and development of prototype radars. The military initially planned to award a full development contract to one company in July 2012, but the program was delayed by budget concerns.

Feeding data to JSpOC, the Space Fence will detect objects as small as a softball at an altitude of 1,200 miles, giving the Air Force the ability to track more than 200,000 satellites, derelict rockets, and other manmade debris. Today's radars and optical sensors can see anything larger than a basketball, or about 23,000 objects in orbit, less than 5 percent of the total number of tiny junk fragments believed to be circling Earth.

Officials say they improvements of the Space Fence will help prevent dangerous collisions in orbit that could threaten astronauts on the International Space Station, take out vital communications or surveillance satellites, and spawn even more debris polluting congested traffic lanes in space.

The Space Fence will replace the Air Force Space Surveillance System radar network, which became operational in 1961 and shut down last year due to across-the-board government budget cuts known as sequestration.

The VHF space surveillance radars were located across the southern United States, but the Air Force continues operating other space-based and ground-based optical and radar sensors to monitor space traffic, including a C-band radar relocated from Antigua to Western Australia and a telescope to be positioned there to improve coverage from the Southern Hemisphere.

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