Earth to Voyager 2: After a Year in the Darkness, We Can Talk to You Again

In the nearly 44 years since NASA launched Voyager 2, the spacecraft has gone beyond the frontiers of human exploration by visiting Uranus, Neptune and, eventually, interstellar space.

A device on board called the command loss timer, something like a dead man’s switch, is used to help the spacecraft determine whether it’s lost contact with Earth and should protect itself by going into a form of electronic slumber. The October test reset the timer, and successfully told the spacecraft to continue operating.