After months of silence, Voyager 1 responded to NASA’s call

Over the past five months, it has seemed likely that 46 year old conversation Finally reached the end.

due to its emission On September 5, 1977, NASA’s Voyager 1 spacecraft beamed from the Kennedy Space Center, diligently sending regular updates to Earth about the health of its systems as well as data collected from onboard instruments.

But by November, the craft went silent.

Voyager 1 is now about 15 billion miles from Earth.Somewhere in the cold interstellar space between our sun and the nearest star, its flight data system Stop communicating Part of the detector can send signals back to Earth. Engineers at the Jet Propulsion Laboratory in Flintridge, Lacada, could tell Voyager 1 was receiving messages, but nothing was being returned.

Linda Spilker, the Voyager mission’s project scientist, said the hardware is starting to age. It’s like restoring an antique car that’s 15 billion miles away.

Week after week, engineers sent troubleshooting commands to the spacecraft, waiting patiently 45 hours each time for a response on Earth, traveling at the speed of light for 22.5 hours to reach the probe, and then 22.5 hours back.

In March, the team discovered that a memory chip that stored part of the flight information system software code had malfunctioned, causing communications from the aircraft to become garbled.

Remote repairs are not possible. There is not enough space anywhere in the system to move the entire code. So, after manually going through the code line by line, engineers broke it down and crammed the pieces into available memory slots.

They sent the order to Voyager on Thursday. Early Saturday morning, the team gathered around a conference table at the Jet Propulsion Laboratory: laptops open, coffee and a box of donuts within reach.

At 6:41 a.m., the spacecraft’s data appeared on the screen. Repair successful.

We went from being very quiet and waiting patiently to cheers, high fives, big smiles and sighs of relief, Spilke said. I’m excited to have meaningful conversations with Voyager 1 again.

Voyager 1 is one of two identical space probes. Voyager 2 was launched two weeks before Voyager 1 and is currently about 13 billion miles from Earth, with the two spacecraft’s orbits diverging somewhere around Saturn. (Voyager 2 continued to communicate uninterrupted on a weekly basis during the Voyager 1 outage.)

They are the furthest man-made objects in the universe, traveling farther from their home star than any other object built by their species. The task of keeping communications open is becoming increasingly difficult. Every 24 hours, Voyager 1 moves 912,000 miles further away from us. As distance increases, the signal becomes slower and weaker.

When the probe visited Jupiter in 1979, it sent back data at a rate of 115.2 kilobits per second, Spilke said. Now, 45 years and more than 14 billion miles later, data is coming back at a rate of 40 bits per second.

Spilke said the team is cautiously optimistic that the probe will remain in contact for another three years, enough time to celebrate the mission’s 50th anniversary in 2027. Conceivably, they could last into the 2030s.

The conversation couldn’t go on forever. Tiny silica particles continually clog the thrusters, keeping the probe’s antenna pointed toward Earth, which could cause communications disruptions. Not enough power. Eventually, one day, both Voyagers will stop transmitting data to Earth, and the first part of their missions will be over.

But the day each spacecraft goes silent, they begin a new era, one that may last much longer.Each probe comes with a metal album cover containing gold recorda gilded copper disk inscribed with sounds and images meant to describe the species that built Voyager and the planet they came from.

Erosion in space is negligible; these images could be read over a billion years or more. If any other intelligent life form encountered one of the Voyager probes and had a way to retrieve the data from the records, they would at least have a chance of figuring out who sent it, even if our species would be long gone by then.