A new spacecraft soon will be joining the armada of probes, rocket bodies and other objects circling Earth. Rather than passing on communications signals, tracking hurricanes or staring at stars, however, this satellite will serve as an orbital eye for tracking space debris.
The Space Based Space Surveillance is an Air Force effort to get better information about the 20,000 or so objects whizzing around the planet. Initially planned as a technology pathfinder, the project will be an operational system. The launch of the first satellite is planned for July.
From a vantage point nearly 400 miles above the planet, the satellite is designed to supplement ground-based radars and telescopes that currently keep track of objects orbiting Earth. The space-based system, however, will not be subject to weather, lighting and other restrictions faced by ground systems.
Space Based Space Surveillanceis even synchronized with Earth's rotation so that it passes over a given point at roughly the same time each day.
"The goal of SBSS is to provide more timely access to space objects of interest... than can be obtained with terrestrial assets," an Air Force representative wrote in an e-mail to Discovery News.
Information collected by SBSS will be used to determine objects' orbital paths and calculate the chances of collisions several days in advance. The project started in 2004 — well before a defunct Russian spacecraft crashed into one of Iridium's communications satellites last year, or the January 2007 Chinese anti-satellite weapons test, which littered space with more than 2,300 pieces of debris.
"These incidents underscore the importance of this system," the Air Force said.
The heart of SBSS is an 11.8-inch visible-light telescope that can be quickly and nimbly pointed around the sky to track satellites, as well as spacecraft launches and orbital maneuvers.
"The gimbal housing is made of beryllium... very stiff, very light material that allowed us to maintain very tight pointing," said Harold Montoya, the SBSS program manager with Ball Aerospace.
The telescope can also be quickly swiveled between targets without having to spend time or fuel repositioning the entire spacecraft, added Boeing spokesman Bob Packard.
The satellite, which is scheduled for launch July 8 from Vandenberg Air Force Base in California, is expected to operate for five years.
The Air Force has spent $535 million on the design, development and production of the SBSS satellite and ground system. A contract for a second SBSS spacecraft is expected to be awarded early next year, the Air Force representative said.