The U.S. Air Force is working on a new surveillance system for keeping track of the thousands of rocket relics, old satellites and other trash whizzing around the planet.
The system, known as "Space Fence," will use S-band radars and computers to track objects as small as about one inch in diameter. At orbital speeds -- roughly 17,500 miles per hour -- even tiny debris can be deadly.
"A one-inch piece of junk can destroy any satellite in orbit," Nicholas Johnson, chief scientist for NASA's Orbital Debris Program Office at the Johnson Space Center in Houston, told Discovery News.
Until 2009, orbital crashes were largely theoretical.
That changed when a defunct Russian weather satellite crashed into an Iridium communications spacecraft, leaving about 3,000 pieces of wreckage in prime space real estate. And those are just the bits that are at least four inches in diameter, the smallest objects that can be reliably tracked with the system in use today.
"This issue has always been on the minds of people who are trying to use space for all the things that it's used for today. ... We really are heavily reliant on space," said John Morse, director of Lockheed Martin's Space Fence Program, one of two firms developing designs for a new system.
"I think people inside (the industry) understood the threat and the possibility of these collisions, but that collision was effective in increasing awareness. The 'big sky' theory was dead. We had to really take additional steps to get the space situational awareness if we're going to use space the way we want to use space," Morse told Discovery News.
The current VHS-based orbital debris tracking system, built in 1961, comprises three transmitting station and six receivers located across the continental United States at sites roughly 33 degrees north of the equator, such as San Diego, Calif., Red River, Ark., and Hawkinsville, Ga.
"It's really reached the end of its life," Morse said.
The catalog of space debris now numbers about 22,000 objects. Johnson expects that number to swell to well over 100,000 once the new space fence is working.
The Air Force on Wednesday took its next step in the upgrade, awarding 18-month design contracts to Lockheed Martin and Raytheon. Each is worth $107 million. The goal is to have an operational system in place in 2015.
© 2012 Discovery Channel