An aging spacecraft manages to turn on a radio transmitter that it has not used since 1981 24,000 million kilometers away

() – The 47-year-old Voyager 1 spacecraft regained contact with NASA, although it is not entirely out of danger, after a technical problem caused a communications outage of several days with the historic mission, which is located billions of kilometers away in interstellar space.

Voyager 1 is now using a radio transmitter it has stopped using since 1981 to stay in touch with its team on Earth as engineers work to understand what went wrong.

As the spacecraft launched in September 1977 ages, the team has slowly turned off components to conserve energy, allowing Voyager 1 to send unique scientific data 15 billion miles away.

The probe is the furthest spacecraft from Earth, operating beyond the heliosphere – the bubble of magnetic fields and particles from the sun that extends far beyond Pluto’s orbit – where its instruments take samples directly from space. interstellar.

The new problem is one of several that the ancient spacecraft has faced in recent months, but the Voyager team continues to find creative solutions so that the famous explorer can advance on its cosmic journey through uncharted territories.

From time to time, engineers send orders to Voyager 1 to turn on some of its heaters and warm up components that have suffered radiation damage over the decades, said Bruce Wagoner, Voyager mission assurance officer. The heat can help reverse radiation damage, which degrades the performance of spacecraft components, he said.

Messages are transmitted to Voyager from mission control at NASA’s Jet Propulsion Laboratory in Pasadena, California, via the agency’s Deep Space Network. The radio antenna system on Earth helps the agency communicate with Voyager 1 and its twin probe, Voyager 2, as well as other spacecraft exploring our solar system.

Voyager 1 then sends engineering data to show how it is responding to commands. A message takes about 23 hours to reach its recipient.

But when a command was sent to the heater on October 16, something triggered the spacecraft’s autonomous failover protection system. If the spacecraft consumes more power than it should, the failover system automatically shuts down non-essential systems to conserve power.

The team discovered the latest problem when it was unable to detect the spacecraft’s response signal over the Deep Space Network on October 18.

Voyager 1 has been using one of its two radio transmitters for decades, called X-band because of the frequency it uses. Meanwhile, the other transmitter, called S-band, which uses a different frequency, has not been used since 1981 because its signal is much weaker than that of the X-band.

Engineers suspect that the failsafe system reduced the rate at which data was sent from the transmitter, changing the nature of the signal shared by Voyager 1 with the Deep Space Network monitors. The Voyager 1 team finally located the probe’s response later, on October 18, by examining signals received by the Deep Space Network.

But on October 19, communication with Voyager 1 appeared to stop completely.

The team believes the failsafe system was activated additionally two more times, which may have disconnected the X-band transmitter and switched the spacecraft to the S-band transmitter, which uses less power, NASA said.

Working on a solution

Although the Voyager 1 team was not sure that the weak S-band signal was detectable due to the spacecraft’s distance from Earth, Deep Space Network engineers located it.

The team won’t send orders to Voyager 1 to turn the X-band transmitter back on until it figures out what triggered the failsafe, which could take weeks. Engineers are being cautious because they want to determine if there are any potential risks in turning on the X band.

If the team can get the X-band transmitter working again, it’s possible the device could transmit data that reveals what happened, Wagoner said.

Meanwhile, engineers sent a message to Voyager 1 on October 22 to check that the S-band transmitter was working and received confirmation on October 24. But it’s not an arrangement the team wants to rely on for too long.

“The S-band signal is too weak for long-term use,” Wagoner said. “So far, the team has not been able to use it to obtain telemetry (information about the health and status of the spacecraft), much less scientific data. “But it allows us to at least send commands and make sure the spacecraft stays pointed at Earth.”

This transmitter switch is just one of several innovative tricks NASA has used this year to overcome the long-lived mission’s communication problems, such as turning on old thrusters to keep Voyager 1’s antenna pointed at Earth and devising a fix for a computer glitch that silenced the flow of scientific data from the probe to Earth for months.