Air Force to Launch Satellite to Keep Close Eye on Space Junk

A new U.S. Air Force satellite built to track space junk and other spacecraft orbiting Earth is set to launch tomorrow (Sept. 25) from Vandenberg Air Force Base in California.

The Space-Based Space Surveillance satellite, called SBSS, is part of an evolving goal to dramatically improve awareness of space debris and other objects around our planet, Air Force officials said.

"Every day, threats to our nation's valuable satellites and space platforms are growing," said Col. J.R. Jordan, vice commander of the Space Superiority Systems Wing at the U.S. Air Force Space and Missile Systems Center, in a statement. "SBSS will revolutionize our ability to find and monitor objects that could harm the space assets we depend on for security, communications, weather forecasting and many other essential services." [Worst Space Debris Moments Ever]

The 2,277-pound (1,031 kilograms) SBSS satellite system will be launched into orbit on a Minotaur 4 rocket, designed by Virginia-based Orbital Sciences Corp. Liftoff is set for 9:41 p.m. PDT (12:41 a.m. Sept. 26? EDT, or 0441 GMT).

The satellite was originally scheduled to launch in Oct. 2009 but was delayed due to technical concerns with its rocket launch vehicle. ?

Space junk sentinel

There are about 500,000 known pieces of space junk orbiting around our planet. Of those, about 21,000 objects are larger than 4 inches (10.1 cm) in diameter, and are being tracked by the Department of Defense as part of the Space Surveillance Network. These are items such as spent rocket stages and broken satellites.

Space junk ? even tiny pieces of it ? can be dangerous because they orbit the Earth at high speeds and pose risks for impacts and collisions.

The SBSS satellite will provide data for the Air Force's Space Surveillance Network, which already keeps an eye on orbital debris. Aerospace juggernaut Boeing is responsible for the overall SBSS program management.

The Colorado-based Ball Aerospace & Technologies Corp. developed, designed, manufactured, integrated and tested the satellite, using the Boeing-built onboard mission data processor.

The overall cost of the SBSS program is about $858 million, Air Force officials said.

Sensors in space

The SBSS spacecraft will be equipped with a visible sensor mounted on an agile, two-axis gimbal. This device will give ground controllers the flexibility to quickly move the camera between targets without needing to reposition the satellite itself or expend additional fuel.

"With its gimbaled camera, reprogrammable onboard processor and open-ground-system architecture, SBSS can respond quickly to today's changing mission requirements and adapt to meet tomorrow's threats as well," said Craig Cooning, vice president and general manager of Boeing Space and Intelligence Systems. "Boeing looks forward to putting these advanced capabilities into action for the Air Force."

The SBSS satellite will collect data to be used in conjunction with observations from ground-based radars and telescopes, but with one clear advantage. As the Air Force's only space-based tracker, SBSS will not be limited by weather, atmosphere or time of day.

"The SBSS team is ready to go on Sept. 25,? said Todd Citron, director of the Boeing Advanced Space and Intelligence Systems. ?We?ve thoroughly rehearsed all plans and procedures, the Satellite Operations Center has been configured for flight operations, and the SBSS satellite and Minotaur launch vehicle are completing final preparations. We?re looking forward to putting this spacecraft into orbit so that it can perform its vital mission."

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