. engineering team NASA’s Voyager 1 spacecraft He tries to solve a mystery: the interstellar explorer, which is currently more than 14 billion miles from Earth, appears to be operating normally, receiving and carrying out commands from Earth, along with collecting and returning scientific data. But the readings from the AACS Expression and Attitude Control System (AACS) do not accurately reflect what is actually happening on board.
The AACS system controls the direction of the 45-year-old spacecraft. Among other tasks, it keeps Voyager 1’s high-gain antenna pointed precisely at Earth, enabling it to send data home. All flags indicate that AACS is still working, but the telemetry data returned is invalid. For example, the data may appear to be randomly generated, or not reflect any possible state that AACS could be in.
The problem wasn’t caused by any onboard fault protection systems, which are designed to put the spacecraft into “safe mode” – a state in which only basic operations are performed, giving engineers enough time to diagnose the problem. The Voyager 1 signal was not attenuated either, indicating that the high-gain antenna remained in its designated orientation with Earth.
An artist’s concept depicting one of NASA’s twin Voyager spacecraft. Humanity’s longest-lived spacecraft will celebrate its 45th anniversary in August and September 2022. Credit: NASA/JPL-Caltech
The team will continue to monitor the signal closely as they continue to determine if the invalid data came directly from AACS or another system involved in producing and transmitting telemetry data. Until the nature of the problem is better understood, the team cannot predict whether this might affect how long the spacecraft can collect and transmit scientific data.
Voyager 1 is currently located 14.5 billion miles (23.3 billion km) from Earth, and it takes light 20 hours and 33 minutes to travel that distance. This means that it takes about two days to send a message to Voyager 1 and get a response—a delay that the mission team is well used to.
Susan Dodd, Voyager 1 and 2 project manager, said: NASAJet Propulsion Laboratory in Southern California. “The spacecraft is about 45 years old, which is far beyond what mission planners expected. We are also in interstellar space – a highly radioactive environment where no spacecraft has flown before. So there are some big challenges for the engineering team. But I think That if there is a way to solve this problem with AACS, our team will find it.”
It’s possible the team may not find the source of the flaw, Dodd said, and will adapt to it instead. If they find the source, they may be able to fix the problem through software changes or perhaps by using one of the spacecraft’s redundant hardware systems.
It wouldn’t be the first time the Voyager team had relied on backup hardware: In 2017, Voyager 1’s initial thrusters showed signs of wear, so engineers showed Switched to another set of thrusters that were originally used during spacecraft planets encounters. Those engines worked, even though they hadn’t been used for 37 years.
Voyager 1’s twin, Voyager 2 (currently 12.1 billion miles, or 19.5 billion km, from Earth), continues to function normally.
Both Voyagers were launched in 1977, and have operated for much longer than expected by mission planners, the only two spacecraft to collect data in interstellar space. The information they provide from this area helped push a file Deeper understanding of the heliosphereThe diffuse barrier that the sun creates around the planets in our solar system.
Each spacecraft produces about 4 watts less electrical power per year, which limits the number of systems the spacecraft can operate. Mission engineering team has Shut off different subsystems and heaters For energy conservation of scientific instruments and vital systems. No science instruments have yet been decommissioned as a result of waning power, and the Voyager team is working to keep the two spacecraft in operation and bring the unique science back beyond 2025.
As engineers continue to work on the mystery presented to them by Voyager 1, mission scientists will continue to search for Make the most of your data Descend from the spacecraft’s unique vantage point.
More about the mission
The Voyager spacecraft was built by Jet Propulsion Laboratory, and both still work. JPL is a division of the California Institute of Technology in Pasadena. The Voyager missions are part of NASA’s Heliophysics System Observatory, sponsored by the Heliophysics Division of the Science Mission Directorate in Washington.
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