Missiles, You’ve Been Warned: New Sat Has Its Orbiting, Infrared Eye on You
By Mark Brown, Wired.co.uk May 9, 2011 | 3:29 pm
Over the weekend, a United Launch Alliance Atlas V rocket carried the next generation of a satellite designed to detect missile launches into orbit.
After a rocky start and a delayed launch, the Atlas V blasted off from Cape Canaveral Air Force station on Saturday morning, hauling the $1.2 billion SBIRS GEO-1 satellite into space.
The GEO-1 is just one soldier in an army of satellites planned to launch into geostationary orbit throughout 2011. Together they form SBIRS (or Space-Based Infra-Red System), which uses infrared sensors to detect and track missile launches from around the globe.
The U.S. military considers the SBIRS program one of its most high priority space programs at the moment. Reconnaissance satellites were given a big pat on the back this month when a fleet of navigation, communications and imaging probes helped flush out Osama bin Laden.
But the current collection of satellites in use just aren’t quite up to snuff when dealing with the threats of 2011. The new GEO-1 satellite will take over from creaky old missile-warning systems, some of which are leftovers from the Cold War.
Missile-warning satellites go back to the 1960s. The MIDAS (or Missile Defense Alarm System) was a system of low Earth orbit satellites — equipped with infrared sensors — that went up throughout the 60s. The Midas 7, which launched 48 years ago (9 May, 1963), detected the first ever missile launch from space.
After dodgy launches and shoddy power supplies, the satellites were deemed obsolete within a few years and the MIDAS program was scrapped. In the 70s it was replaced with DSP (or Defense Support Program).
These new reconnaissance satellites would orbit the Earth from ten times the altitude of MIDAS (floating about in geostationary orbit, meaning they remain above the same spot on the Earth’s surface, rather than low Earth orbit), providing the military with a constant view of the entire planet’s infrared activity. The 23 satellites proved so successful that most of them are still up there now.
But the SBRIS system is a big upgrade. The satellite’s sensor is rather faster, allowing it to look at one location and then gaze at another rapidly. It’s also more sensitive than DSP, and its revisit time is significantly shorter. With SBRIS, raw, unprocessed data can be downloaded to stations on the ground, so the globe’s radiometric scene can be observed in real time from Earth.