NASA's Voyager 1 mysteriously lost touch with Earth

NASA's farthest spacecraft gave mission control a scare when it inexplicably went silent and missed two days of planned check-ins. The nail-biting incident happened just two weeks ago, when the Deep Space Network didn't receive a call from Voyager 1 on either Oct. 18 or 19. But before the agency could send repair commands, the spacecraft, now outside the solar system, signaled back on Oct. 20. No communication outages have happened since. Engineers still don't know what caused the problem. So far, the team has discovered that one set of thrusters shut down, leaving a backup set to take over. The thrusters are small engines that point and steady the spacecraft. Voyager 1's computers do this automatically whenever they detect an issue with the active thrusters to ensure the spacecraft is in a safe mode.