The Voyager 1 spacecraft in interstellar space disabled one of its radio transmitters, causing a temporary loss of communication. NASA experts are currently working to determine the root of the problem.
Voyager 1 was launched in 1977. During its flight, it has traveled almost 25 billion kilometers from the Earth. It is the most distant object in the Universe made by human hands. It takes 23 hours for a command sent from Earth to reach Voyager 1. It takes another 23 hours to get a response.
On October 16, the mission team sent the vehicle a command to turn on one of the heaters. Although Voyager 1 was supposed to have enough power to execute it, the command activated the fault protection system. Engineers became aware of the problem when NASA’s Deep Space Communications Network failed to detect the vehicle’s signal on October 18.
Generally, Voyager 1 communicates with Earth using an X-band radio transmitter, named for the frequency it uses. While analyzing the data, the team suggested that Voyager 1 shut it down due to the fault protection system that autonomously responds to problems on board. For example, if the vehicle exceeds its power reserve, the fault protection system will conserve energy by shutting down systems that are not vital.
Apparently, after receiving the command, the fault protection system reduced the rate at which the transmitter sent data. This mode requires less power from the spacecraft, but the X-band signal is altered. Engineers found a signal later that day, and in other respects, Voyager 1 seemed to be in stable condition.
Then, on October 19, communication ceased completely. The team hypothesized that Voyager 1 had two other fault protection systems that shut down the X-band transmitter and switched to a second radio transmitter operating in the S-band. Although it uses less power, Voyager 1 hasn’t used it to communicate with Earth since 1981. This transmitter uses a different frequency than the X-band transmitter, and its signal is much weaker. Therefore, engineers weren’t sure if its signal could be detected on Earth because of the distance to the spacecraft.
Without risking turning on the X-band until the cause of the fault protection system was determined, the team sent a command on October 22 to confirm the S-band transmitter was operational. On October 24, the Deep Space Communications Network picked up an extremely weak signal from the edge of the Solar System, confirming that Voyager 1 had successfully switched to a backup transmitter.
The mission team is now working to gather information to help figure out what happened and return Voyager 1 to normal operations. Given the enormous distance to the vehicle and the complexities involved, as well as its age, this process can take from a few days to a few weeks, or even longer.
Earlier we told you about how NASA had to shut down one of Voyager 2’s science instruments to extend its life.
Provided by NASA
