A Boeing Co. surveillance spacecraft that will provide the U.S. Air Force with its first space-based sensor to detect debris, spacecraft or other distant space objects without interference from weather, atmosphere or time of day is ready for launch, the company announced Tuesday.

The Space Based Space Surveillance (SBSS) satellite and ground system, developed in partner with Ball Aerospace & Technologies Corp., have completed final testing and the SBSS Block 10 spacecraft is scheduled to leave into orbit Saturday from Vandenberg Air Force Base in Lompoc, Calif.

"Every day, threats to our nation’s valuable satellites and space platforms are growing," said Col. J.R. Jordan, vice commander, Space Superiority Systems Wing, 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."

The U.S. Air Force Space Surveillance Network (SSN) has ground-based radars and optical telescopes worldwide to monitor thousands of space objects, but the instruments' monitoring abilities are limited in coverage, speed and sensitivity.  Once in orbit, the SBSS satellite will provide around-the-clock data collection of objects in deep space and low-earth orbit, and work in conjunction with the SSN to support spaceflight safety and other space situational awareness. 

The SBSS spacecraft includes a visible sensor mounted on an agile, two-axis gimbal so ground controllers can quickly move the camera to find and track objects without repositioning the entire spacecraft. A gimbal is a swiveling device consisting of a ring or base mounted on an axis that allows an object mounted in or on it to remain horizontally suspended and tilt freely in any direction even when the surrounding environment is unstable. (Think the mechanical device that holds a globe and allows it to rotate.)

Compared to previous space sensors, SBSS provides improvements such as twice the sensitivity and twice the speed at detecting threats.

SBSS has a design life of seven years and was built on the success of the most recent orbiting sensor, the MSX Space-based Visible Sensor, which ended operations in December 2008.

The satellite was shipped from Ball Aerospace's facility in Boulder, Colo., in May. The Air Force and Boeing completed the final mission operations dress rehearsal in June.

Reach reporter Len Ly here.