Earlier this week, an amateur radio astronomer named Scott Tilley decided to have a look for the presence of secret military satellites. It's something he apparently does semi-regularly, and in this case his search was inspired by the Zuma satellite, a secret US government payload that was reportedly lost on its way to space. Most accounts have suggested that Zuma failed to make it to orbit, but the secrecy of the mission (we've got no clear idea what Zuma even was) means that everything about its fate is unclear. Tilley could either find a hint that Zuma is up there—or stumble across some other hardware put into space by other countries.
Instead, he found an undead NASA mission.
Given the clear indication of a radio signal, Tilley matched its orbit to a NASA satellite called IMAGE. IMAGE was launched back in 2000 with a mission of studying Earth's magnetosphere. Over five years of operation, it created a three-dimensional map of the charged particles that move along Earth's magnetic field lines. But contact was lost in 2005, and NASA eventually attributed that to a one-time event in the power system that the satellite wasn't designed to recover from.