This image details an artist's concept of the NASA Voyager 1 spacecraft with its antenna pointing toward Earth. Photo courtesy of NASA/UPI | License Photo
May 19 (UPI) -- NASA engineers are investigating a mystery with telemetry data from the aging Voyager 1 probe.
The Voyager 1 probe, currently 14.5 billion miles from Earth, is receiving and executing commands from NASA team on Earth and sending back science data, according to a NASA statement.
But data readouts from its attitude articulation and control system, or AACS, which controls the spacecraft's orientation, don't reflect what the Voyager actually does, engineers at NASA's Jet Propulsion Laboratory said.
The AACS keeps Voyager 1's high-gain antenna pointed precisely at Earth, which allows it to send data home.
Voyager 1's signal hasn't weakened, which suggests its antenna remains properly aligned, but the telemetry data it's returning appears random or impossible, engineers said.
All signs suggest that the AACS is working, and the telemetry data anomaly hasn't triggered any onboard fault protection systems, which would put the spacecraft into "safe mode," where only essential operations could be performed.
The engineering team plans to continue monitoring the signal to determine whether the invalid telemetry data is coming directly from AACS or another system involved in producing and sending such data.
Due to the spacecraft's distance from Earth, it takes two days for the team on the ground to send a message to Voyager 1 and get a response.
"Until the nature of the issue is better understood, the team cannot anticipate whether this might affect how long the spacecraft can collect and transmit science data," NASA and JPL said in the statement.
Voyager 1's twin, Voyager 2, currently 12.1 billion miles from Earth, still operates normally.
Both probes were launched in 1977 and are the only spacecraft to collect data on interstellar space, according to NASA.
They've also provided new insights into the heliosphere, a protective bubble the Sun has created that extends past the orbit of Pluto.
"A mystery like this is sort of par for the course at this stage of the Voyager mission," said Suzanne Dodd, project manager for Voyager 1 and 2 at JPL.
"The spacecraft are both almost 45 years old, which is far beyond what mission planners anticipated. We're also in interstellar space -- a high radiation environment that no spacecraft have flown in before. So there are some big challenges for the engineering team. But I think if there's a way to solve this issue with the AACS, our team will find it."
Paola Rosa-Aquino
Thu, May 19, 2022
An illustration depicting one of NASA's twin Voyager spacecraft. Both Voyagers have entered interstellar space.
NASA said Voyager 1 is sending data that doesn't match the spacecraft's movements.
The veteran spacecraft has been exploring our solar system and interstellar space since 1977.
It is now 14.5 billion miles away from Earth, making it the most distant human-made object.
NASA's Voyager 1 is continuing its journey beyond our solar system, 45 years after it was launched. But now the veteran spacecraft is sending back strange data, puzzling its engineers.
NASA said on Wednesday that while the probe is still operating properly, readouts from its attitude articulation and control system — AACS for short — don't seem to match the spacecraft's movements and orientation, suggesting the craft is confused about its location in space. The AACS is essential for Voyager to send NASA data about its surrounding interstellar environment as it keeps the craft's antenna pointing right at our planet
"A mystery like this is sort of par for the course at this stage of the Voyager mission," Suzanne Dodd, a project manager for Voyager 1 and 2 at NASA's Jet Propulsion Laboratory, said in a statement. "The spacecraft are both almost 45 years old, which is far beyond what the mission planners anticipated." NASA said Voyager 1's twin, the Voyager 2 probe, is behaving normally.
Launched in 1977 to explore the outer planets in our solar system, Voyager 1 has remained operational long past expectations and continues to send information about its journeys back to Earth. The trailblazing craft left our solar system and entered interstellar space in 2012. It is now 14.5 billion miles away from Earth, making it the most distant human-made object.
An engineer works on a dish-shaped Voyager high-gain antenna on July 9, 1976.NASA/JPL-Caltech
NASA said that from what its engineers can tell, Voyager 1's AACS is sending randomly generated data that does not "reflect what's actually happening onboard." But even if system data suggests otherwise, the spacecraft's antenna seems to be properly aligned — it is receiving and executing commands from NASA and sending data back to Earth. It said that so far the system issue hasn't triggered the aging spacecraft to go into "safe mode," during which it carries out only essential operations.
"Until the nature of the issue is better understood, the team cannot anticipate whether this might affect how long the spacecraft can collect and transmit science data," NASA said.
Dodd and her team hope to figure out what's prompting the robot emissary from Earth to send junky data. "There are some big challenges for the engineering team," Dodd said. A major one: It takes light 20 hours and 33 minutes to get to Voyager's current interstellar location, so a round-trip message between the space agency and Voyager takes two days.
"But I think if there's a way to solve this issue with the AACS, our team will find it," Dodd added.