There are more than 2,000 active satellites orbiting Earth. At the end of their useful lives, many will simply burn up as they reenter the atmosphere. But some will continue circling as "zombie" satellites — neither alive nor quite dead.
Scott Tilley, an amateur radio operator living in Canada, has a passion for hunting them down.
Recently, Tilley got interested in a communications satellite he thought might still be alive — or at least among the living dead. LES-5, built by the Massachusetts Institutehe found a paper describing the radio frequency that LES-5, an experimental military UHF communications satellite, should be operating on — if it was still alive. So he decided to have a look.
"This required the building of an antenna, erecting a new structure to support it. Pre-amps, filters, stuff that takes time to gather and put all together," he says.
British Columbia, where Tilley lives, was on lockdown. Like many of us, suddenly Tilley had time on his hands. He used it to look for LES-5, and on March 24, he hit the ham radio equivalent of pay dirt.
"The reason this one is kind of intriguing is its telemetry beacon is still operating," Tilley says.
In other words, says Tilley, even though the satellite was supposed to shut down in 1972, it's still going. As long as the solar panels are in the sun, the satellite's radio continues to operate. Tilley thinks it may even be possible to send commands to the satellite.
The MIT lab that built LES-5 still does a lot of work on classified projects for the military. NPR contacted its news office to ask if someone could say more about LES-5 and whether it really could still receive commands.
But after repeated requests, Lincoln Laboratory finally answered with a "no comment." It seems that even elderly satellites still might have a few secrets they want to keep.