By Mike Mount, CNN Senior National Security Producer
The Air Force wants to rebuild a “fence” around Earth to keep the riff-raff out.
Sounds like a Hollywood script to counter aliens or asteroids but it's a real program the military wants to update at an estimated cost of $3.5 billion.
Just don't expect any space cowboys digging post holes and wrangling barbed wire in orbit.
The Space Fence program is a series of radar signals managed by the Air Force since the early 1960's that has been tracking an ever-growing pile of rocket and satellite parts and other man-made fragments that zoom around Earth’s vicinity at thousands of miles per hour.
The military tracks about 20,000 pieces of so-called “space junk” but the actual size of the problem is ten times larger than that. Pieces that need tracking are as small as a softball to as large as a bus.
Regardless of size, the debris is a danger to manned space flight, such as the International Space Station, and unmanned operations, like the hundreds of satellites circling the planet at any one time.
Those satellites bring in television, run GPS and carry cell service, so the everyday and commercial stakes of managing the problem are high. The military also operates communications and other satellites.
The Air Force alerts NASA and private satellite companies about any “space junk” threatening to collide with one of their spacecraft.
"As every collision creates more and more objects, the problem only gets worse over time, it won't get better over time," says Scott Spence, director of Raytheon's Space Fence Program.
Like an old ranch fence, the Air Force Space Fence is worn out and needs to be “restrung” before something slips through.
Defense contractors Raytheon and Lockheed Martin are competing for a $3.5 billion contract to come up with an improved system that can identify more and smaller pieces. An announcement on a new contract is expected at year’s end.
"The fence will have greater sensitivity, allowing it to detect, track and measure and object the size of a softball orbiting more than 1,200 miles in space," according to an Air Force information sheet about what it expects.
Improved capabilities will also allow the military to receive evidence of satellite break-ups, collisions and unexpected satellite maneuvers, the Air Force said.
The Air Force said it plans on putting up to two radar systems. At least one will be located in the Marshall Islands in the South Pacific and the new system will be integrated with the existing system to better track debris.
The Air Force expects construction to begin at the end of 2013 and have a completed system up and running in 2017.
But what about the overall problem of what to do with the debris? It seems as if the technology is not there yet.
"Space has a lot of challenges. The physics of overcoming how much space you want to cover if you want to clean up the debris around the Earth is a daunting one," Spence said.
"If you can prevent a collision from occurring by having better fidelity of what's up there and you can prevent 4,000 objects from being created from a collision when a satellite collides, that's more cost effective to do than trying to clean up the 4,000 objects after the fact," he added.
Like any good fence, Space Fence makes for good neighbors if you can keep track of them.