It’s not for keeping out Klingons, though. Officially known as the Air Force Space Surveillance System, it’s used for keeping track of objects in or near Earth’s orbit.
Three transmitting stations in Alabama, Arizona, and Texas emit radio waves into space, which bounce off objects and are received by six stations in Arkansas, California, Georgia (two stations), Mississippi, and New Mexico.
The Space Fence network extends east to west across the 33rd parallel, detecting any object that passes over. The receiving stations are reportedly sensitive enough to track an object the size of a basketball orbiting 17,200 miles above the Earth’s surface.
Those objects include satellites and space junk. More than 10,500 individual objects are tracked.
Having massive radio arrays spread out across the United States, and calling that series a contraptions a Space Fence, seems ripe for conspiracy theory. While the Fence doesn’t track border-jumping aliens, it does do important work.
Objects in space move very fast (about 17,000 mph in Earth orbit), which makes them dangerous. The Fence can warn the International Space Station if a piece of debris gets too close, or help track a deda satellite as it falls out of orbit, plotting where it will crash.
There’s also an intelligence component to the mission: the Space Fence can detect when a spy satellite passes over the U.S., and it can calculate an object’s country of origin from its launch trajectory. Just think of what the NSA could do with it.
The Space Fence was originally run by the Navy, but it’s now administered by the Air Force’s 20th Space Control Squadron (yes, there really is such a thing). The squadron is at Eglin Air Force Base in Florida, while the data from the Fence is analyzed at the Alternate Space Control Center in Dahlgren, Virginia.
So in a time when it seems like the government can’t do anything right, the Air Force’s space traffic controllers are monitoring thousands of objects zipping around thousands of miles above our heads.
At least for now they are. The Air Force is planning to shut down the Space Fence,which will reportedly save $14 million a year. The Air Force hopes to replace it with a more accurate system.
Hopefully the INS will be able to keep border-hopping aliens out of the country in the meantime.