crossing the heliosfera, a protective “bubble” of particles and magnetic fields created by the Sun, which surrounds the solar system, NASA’s Voyager 1 spacecraft continues to return science data as normal. Or almost. A curious problem in the system responsible for guiding the probe is puzzled by his team of engineers.
They noted that readings from the probe’s Attitude and Articulation Control System (AACS) do not reflect what is actually going on inside the spacecraft. In addition to controlling Voyager 1’s orientation, AACS keeps the antenna pointed at Earth, allowing data exchange.
The signals indicate that the AACS is working, but the telemetry data sent to Earth does not agree with this. Despite this problem, the probe’s safe mode, a protection system where only essential operations are performed in the event of a failure, was not activated.
In other good news, the signal from the probe has not weakened, indicating that the antenna remains correctly pointed towards the Earth. The NASA team will continue to monitor this signal to see if the problem is with AACS or another system involved in collecting and sending telemetry data.
Investigate a remote problem
Until the root of the problem is discovered, there is no way of knowing how it could interfere with the work of the probe. Currently the Voyager 1 is 23.3 billion kilometers from Earthso far that light takes more than 20 hours to travel that distance.
It therefore takes nearly two days to send a message to the probe and receive its response. Suzanne Dodd, project manager for Voyager 1 and 2 at the Jet Propulsion Laboratory (JPL) in Nasaexplained that the probe is in the interstellar spacea high radiation environment never visited before.
This poses major challenges for engineers. “But I think if there’s a way to fix this problem with AACS, our team will find it,” Dodd added. It is also possible that the problem is not solved and that the team must adapt to it.
If they have found the source of the problem, they will try to fix it with some software modifications or by using one of the backup systems. In 2017, when Voyager 1’s thrusters showed signs of failing, engineers activated another set used during its passage through planets.
An identical copy of the spacecraft, Voyager 2 — currently 19.5 billion km from us — continues to operate normally. Both came out in 1977 and exceeded the working time intended by their creators, in addition to being the only probes to collect information on interstellar space.
Due to the distance, the probes produce approximately 4 watts less electrical power each year, which limits the number of systems in operation. Engineers have already shut down several subsystems and heaters to prioritize the use of science instruments and fundamental systems. The team continues to work to have both probes collect and return important data to Earth beyond 2025.