NASA restored communication with the Voyager 1 spacecraft on October 20 following a temporary signal loss during scheduled attempts on October 18 and October 19. Launched in 1977, the aging probe has traveled 16 billion miles (26 billion kilometers) from Earth into interstellar space beyond the heliosphere. According to NASA, engineers are investigating the root cause of the outage while preparing the spacecraft to reach a distance of one light-day—16.09 billion miles (25.89 billion kilometers)—on November 18.

Deep Space Network Detects Automatic Thruster Swap

The communication interruption occurred when the Deep Space Network (DSN) array failed to detect radio signals from Voyager 1 during two scheduled checks spaced 24 hours apart. NASA reported that one group of the spacecraft's primary thrusters went offline during the outage. The onboard computers automatically activated backup thrusters, placing Voyager 1 into a safe operational configuration and pausing standard activities.

Kareem Badaruddin, Voyager mission manager at NASA’s Jet Propulsion Laboratory (JPL) in Southern California, stated that engineers had not seen the spacecraft execute this specific automated maneuver previously. Badaruddin noted that the team feels relieved to resume contact and remains eager to determine what triggered the thruster system transfer.

Power Management and Interstellar Communication Delay

Reaching the target distance on November 18 will establish a 24-hour transmission delay in each between Earth and Voyager 1. Suzanne Dodd, Voyager project manager at JPL, explained that transmitting a message to the spacecraft requires waiting two days to receive a returned response.

The probe loses roughly 4 watts of power annually as its plutonium power source decays. To conserve energy, JPL engineers executed a power-saving maneuver known as the "big bang," which replaced three onboard devices with lower-power alternatives. NASA indicated that this modification prevents the immediate shutdown of an additional science instrument, which would have otherwise been required by summer 2027. NASA engineers continue to monitor data from Voyager 1 as the team works to complete its investigation into the October thruster system event.