Sign up for CNN’s Wonder Theory science newsletter. Explore space with news of fascinating discoveries, scientific advancements and more.
CNN
—
The Voyager 1 spacecraft is continuously transmitting scientific data from uncharted territory for the first time since a computer malfunction aborted NASA’s historic mission seven months ago.
Voyager 1, currently the farthest spacecraft from Earth, stopped communicating consistently with mission control in November 2023. The probe seemed caught up in a Groundhog Day scenario, with its Flight Data System’s Telemetry Modulation Unit sending back an indecipherable repeating pattern of code from billions of miles away.
Thanks to ingenious fixes from the Voyager mission team, communications with the spacecraft were restored, and in April engineering data began streaming to mission control, keeping the team informed of the spacecraft’s health and operational status.
But data from Voyager 1’s four science instruments that study plasma waves, magnetic fields and particles has remained hard to come by. This information is crucial for showing scientists how particles and magnetic fields change as the probe travels farther away.
On May 19, the Voyager team sent commands to the spacecraft to begin transmitting science data. Two of the instruments responded, but data acquisition from the other two took longer and required recalibration. All four instruments are now transmitting usable science data, the team said. Latest update shared by NASA on June 13th.
Voyager 1’s Flight Data System is responsible for collecting information from the spacecraft’s scientific instruments and combining it with engineering data that reflects the health of the probe. Mission Control on Earth, based at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, receives that data in binary code — a series of 1s and 0s.
It took time and some innovative thinking for Voyager mission specialists to decipher the spacecraft’s garbled code, but once they were done, they discovered the source of the problem: 3% of the flight data system’s memory had been corrupted.
A single chip responsible for storing part of the system memory, including some of the computer’s software code, was not functioning properly, and the code on the chip was lost, rendering Voyager 1’s science and engineering data unusable.
With no way to repair the chip, the team stored the affected code from the chip in a different location in the system’s memory. Because they couldn’t identify a location large enough to store all the code, they broke the code into sections and stored them in various locations within the flight data system.
There are still minor tweaks required to manage the impact of the first issue.
“Among other tasks, engineers will resynchronize timing software in the spacecraft’s three onboard computers to ensure they execute commands at the right time,” the agency said. “The team will also maintain the digital tape recorders that record data from the plasma wave instrument that is transmitted back to Earth twice a year.”
(Most of the Voyager science data is transmitted directly to Earth and is not recorded.)
Meanwhile, Voyager 1 is back to doing what it does best: sharing insights from uncharted regions of space.
The spacecraft is currently about 15 billion miles (24 billion km) from Earth, while its sister spacecraft, Voyager 2, has traveled more than 12 billion miles (20 billion km) from Earth. The twin probes were launched a few weeks apart in 1977 and initially flew around Jupiter, Saturn, Uranus and Neptune before their mission was extended to 46 years and is still ongoing.
Both are in interstellar space and are the only spacecraft that operate beyond the heliosphere, the sun’s bubble of magnetic fields and particles that extends far beyond the orbit of Pluto.
As the only extension of humanity outside the protective bubble of the heliosphere, the two probes are on their own, traveling in different directions through space.
Think of the planets in our solar system as existing on a flat surface: Voyager 1’s orbit rose up out of that plane after it passed Saturn, and Voyager 2’s orbit fell down out of that plane after it passed over Neptune, Suzanne Dodd, Voyager project manager at JPL, previously told CNN.
These long-lived probes are the only two spacecraft to directly sample interstellar space with instruments, and the information they collect is helping scientists learn about the comet-like shape of the heliosphere and how it protects Earth from energetic particles and radiation in interstellar space.
Over time, both spacecraft have encountered unexpected issues and communication interruptions, including a seven-month period in 2020 when Voyager 2 was unable to communicate with Earth. In August 2023, mission teams used Longshot’s “Shout” technology to restore communication with Voyager 2 after a command accidentally pointed the spacecraft’s antenna in the wrong direction.
“I don’t know what the future holds for the Voyagers, but it’s always amazing how they keep going,” Dodd said in April.