Plans for a new military satellite-tracking telescope could help astronomers spot unusual changes in the night sky.
The 3-metre Space Surveillance Telescope (SST), a US$65-million project overseen by the Defense Advanced Research Projects Agency (DARPA), part of the Pentagon, is designed to improve the US Air Force's ability to monitor satellites and orbiting space debris. Work on the telescope's detectors is set to begin in October and the telescope should be complete by 2008.
Building a telescope that can scan the sky rapidly for fast-moving satellites will require some unusual technology, according to Timothy Grayson, who oversees the SST project at DARPA's Special Projects Office in Arlington, Virginia. Most telescopes use two mirrors to focus light onto detectors, but the SST will add an extra mirror to reduce distortion around the edge of its images, effectively widening the field of view. The three-mirror system will be difficult to set up, says Grayson. The design will also require the development of new, curved charge-coupled device detectors to capture digital images from the telescope.
The telescope's primary client is likely to be the military, but some data may be made available to researchers. The broad field of view and sensitive detector could, for example, help astronomers search for stars of variable brightness. Grayson has met officials from NASA and the National Science Foundation (NSF) to discuss how the telescope could benefit future research.
Civilian use of military telescopes is not unprecedented, says Jim Breckinridge, programme director for Advanced Technologies and Instrumentation at the NSF's Division of Astronomical Sciences in Arlington, Virginia. His office has an agreement with the Air Force Office of Scientific Research that allows scientists to use the Air Force's 3.67-metre Advanced Electro-Optical System telescope in Hawaii.