'15 billion miles away': How NASA rescued Voyager-1 from the jaws of death

Produced by: Tarun Mishra

Partial Restoration of Voyager 1

Engineers successfully restored functionality to Voyager 1, a 1970s-era spacecraft, after five months of remote troubleshooting, demonstrating the feasibility of resuming normal operations from a distance of 15 billion miles.

Ground Team's Efforts

A team of scientists and engineers at NASA's Jet Propulsion Laboratory gathered, either in person or virtually, to await a signal from Voyager 1 after sending a command to recode part of the spacecraft's memory.

Breakthrough Moment

After a lengthy wait, engineers received a breakthrough signal from Voyager 1, indicating partial restoration of communication with the spacecraft, located over 15 billion miles away from Earth.

Troubleshooting Challenges

Voyager 1 had ceased transmitting data in November, leading to a months-long troubleshooting effort to identify and rectify the issue, with the ground team facing challenges due to the spacecraft's considerable distance.

Source of the Problem

Through extensive analysis, engineers determined that a malfunctioning chip in the Flight Data Subsystem (FDS) memory was responsible for the data transmission failure, likely due to cosmic ray interference or hardware aging.

Innovative Command Strategy

Engineers devised a novel command to retrieve a readout of Voyager 1's memory, enabling them to pinpoint the location of the problem within the FDS memory.

Transplanting Code

To address the issue, engineers relocated the affected code into different sections of the FDS memory, dividing it into smaller segments due to memory constraints and modifying the code as necessary for compatibility.

Challenges of Older Technology

Voyager 1's aging hardware and lack of ground simulators presented additional challenges for engineers, who relied on manual inspection and verification to ensure the effectiveness of their repairs.

Future Steps

While partial restoration was achieved, further steps were required to relocate the remaining code responsible for science data packaging, with engineers planning to assess options and make decisions in the coming weeks.

Scientific Implications

Restoring Voyager 1's functionality was crucial for retrieving valuable scientific data, particularly regarding cosmic rays, magnetic fields, and plasma environments in interstellar space, providing insights into phenomena like "Pressure Front 2."