First Successful Contact With NASA’s Voyager 1 After Months

On November 14, 2023, the Voyager 1 probe stopped sending updates to Earth, starting a period of silence that lasted five months during which the members of the Voyager engineering team at NASA’s Jet Propulsion Laboratory in Southern California attempted to resolve the issue.

They were sending commands to the spacecraft successfully but it wasn’t returning its status. After identifying the malfunction in March, they were able to repair a piece of flight system code and get updates on the health and status of the probe on April 20.

Illustration Voyager — *Voyager 1 render. Credits: NASA/JPL*

Voyager 1 is one of the most precious missions that NASA has ever accomplished, collecting crucial information from Jupiter, Saturn, and their moons in the early 80s . It is now traveling through interstellar space, 24 billion kilometers away from Earth. Indeed, the spacecraft has earned the reputation of being the most distant human-made object in existence.

An intricate coding problem

The fault concerned one of the spacecraft’s three computers, called the flight data subsystem (FDS), which is responsible for the packaging of the data collected by the onboard instrumentation before it’s sent to Earth.

*Members of the Voyager flight team celebrate in a conference room at NASA’s Jet Propulsion Laboratory on April 20. Credits: NASA/JPL-Caltech*

The error was caused by a single chip that stopped working and was responsible for storing a portion of FDS memory. Engineers had to move the affected code to a different memory slot despite not having large enough allocations. They divided the code into sections so that they would fit correctly and they also needed to adjust those sections to ensure they still functioned as a whole.

The probe isn’t able to send back to Earth science data yet but the team will work in the next weeks to make it fully operational.

Voyager 2 out of the radar last year

This is not the first time a Voyager probe has been in trouble. On July 21, 2023, Voyager 2 had serious issues communicating with NASA’s Deep Space Network ground antennas. A series of planned commands sent to Voyager 2 inadvertently caused the antenna to deviate 2 degrees away from Earth, thereby interrupting any communication attempt.

*Deep Space Network, Deep Space Station 43 (DSS-43), a 70-meter antenna at the Canberra Deep Space Communications Complex near Canberra, Australia. Credits: NASA/JPL-Caltech*

Through the Deep Space Network facility in Canberra, Australia, the agency sent an interstellar command to the probe, instructing it to reorient and aim its antenna back toward Earth. Communication was successfully reestablished in the end.

Voyager mission

Voyager 2 was launched on August 20, 1977, while Voyager 1 was launched on September 5 of the same year. They were both delivered to space by Titan-Centaur expandable rockets from the NASA Kennedy Space Center at Cape Canaveral, Florida. Voyager 2 was so named because, despite being launched first, it would have been the second of the two probes to reach the four gas planets of our solar system.

The launch window was determined by the alignment of the four giant outer planets that allowed the spacecraft to swing from one to another thanks to gravity and occurs once every 176 years.

The primary mission was the exploration of Jupiter and Saturn, but thanks to the surprising durability of the probes, built to last 5 years, their operational life was extended and continues today, pushing the boundaries of human exploration to the outermost edge of Sun’s domain and beyond.

*Jupiter’s Great Red Spot photographed by Voyager probes. Credits: NASA/JPL*

*Saturn with its moons, Tethys and Dione, photographed by Voyager probes. Credits: NASA/JPL*

During the first phase of the mission, Voyager 1 and 2 studied closely the two gas giants of our solar system, collecting revolutionary data about active volcanoes on Jupiter’s moon Io and Saturn’s rings. They provided enough material to dramatically change our knowledge about planets’ genesis.

Eventually, the two spacecraft ended up exploring all the giant outer planets of our solar system, their unique systems of rings, their magnetic fields, and 48 of their moons.

In the depths of the cosmos

After the last rendezvous with Uranus and Neptune, the investigation of solar system boundaries, the outer limits of the Sun’s sphere of influence, and possibly beyond, became the main objectives.

Graphics of the Heliosphere Credits: voyager.jpl.nasa.gov — *Graphics of the Heliosphere. Credits: NASA/JPL*

This second phase of the probes’ lifetime is named Voyager Interstellar Mission and is crucial to obtaining measurements of the interstellar medium such as density and composition.

It will last until 2025 when the spacecraft’s ability to generate electrical power will come to an end. The Voyagers are destined to wander the Milky Way eternally.