Voyager 1 has little time left in interstellar space. An ambitious ‘Big Bang’ fix may change that

Voyager 1, The spacecraft farthest from our planetshut down the power of another science vehicle while exploring uncharted interstellar space; It’s a move that could buy time for an ambitious attempt to extend the probe’s impressive lifespan.

On April 17, NASA sent a command to disable the spacecraft’s Low Energy Charged Particles experiment (LECP) to save power as Voyager 1 moves further and further from Earth. agency. The same instrument that measured the structure of the space between stars was switched off on Voyager 1’s twin, Voyager 2, in March 2025.

The probes were launched weeks apart in 1977, each Pack of 10 science instruments It was intended to assist in close transits of Jupiter, Saturn, Uranus, and Neptune. Voyager 1 is currently about 25.40 billion kilometers (16 billion miles) away from Earth, while Voyager 2 is about 21.35 billion kilometers (13 billion miles) away.

They are the only active spacecraft beyond. heliosphereThe sun’s bubble of magnetic fields and particles that extends far beyond Pluto’s orbit. Keeping the probes operational for much longer than their expected five-year lifespan meant shutting down different devices over time to preserve each spacecraft’s limited power supply.

“While shutting down a science vehicle is no one’s choice, it is the best option available,” said Kareem Badaruddin, Voyager mission manager at NASA’s Jet Propulsion Laboratory in Pasadena, California.
“Voyager 1 still has two operational science instruments, one that listens for plasma waves and one that measures magnetic fields. They still work great, sending back data from a region of space that no other human-made instrument has explored. The team is focused on keeping both Voyagers operational for as long as possible.”

Three operating science instruments remain on Voyager 2.

Engineers hope the final act of sacrifice could keep Voyager 1 running long enough to potentially roll out an upgrade nicknamed “The Big Bang” that could allow the record-breaking probe to continue exploring deeper into space and perhaps even reboot some science instruments.

We solve the ‘Big Bang’ problem

Both Voyager probes are working on radioisotope thermoelectric generators, or devices that convert the heat provided by decaying plutonium into electricity. The probes have been losing about 4 watts of power per year since they began flying nearly half a century ago.

Managing slow but steady power consumption forces engineers into a high-stakes balancing act. Turning off instruments and heaters in the freezing temperatures of interstellar space can cause probes to cool beyond repair. If the fuel lines freeze, the spacecraft will lose the ability to keep its antennas pointed toward Earth and NASA crews will lose communication with them, effectively ending missions.

Engineers believe that shutting down the majority of the Low-Energy Charged Particles experiment will allow Voyager 1 to continue flying with two functional instruments for about a year. Extending the mission’s lifespan this much could mark Voyager 1’s 50th anniversary; It’s a deadline that sets the stage for one of the team’s most entrepreneurial moves yet.

The team will attempt to make a major change to the Voyager probes; While turning off some electrical devices, it will turn on alternatives that draw less power; It will maintain the balance of keeping each spacecraft warm while continuing to collect scientific data.

This “Big Bang” will occur simultaneously for a spacecraft. Voyager 2, which has slightly more power and is relatively closer to Earth, will initially serve as the test subject in May and June.

If the Big Bang is successful on Voyager 2, the team will try the same maneuver on Voyager 1 in July, and if that works, the Low-Energy Charged Particles experiment could get a second chance to continue collecting important data in interstellar space.

“With LECP, we explored the properties and effects of cosmic rays and solar particles and ‘felt’ the changes in the region around us that marked the time Voyager passed from the solar system into interstellar space,” Matt Hill, the instrument’s principal investigator at the Johns Hopkins Applied Physics Laboratory, wrote in an email.

“We hope that Voyager engineers’ latest plan will reactivate the LECP on Voyager 1, allowing us to continue learning about the surprises that await Voyager in these distant regions of space,” he added. “They have a good track record of working miracles that extend the remaining power supply, but eventually that streak will come to an end.”

An unexpected drop in power

During a planned return maneuver on February 27, the mission team noticed Voyager 1’s power levels had unexpectedly dropped. The spacecraft routinely conducts such maneuvers to calibrate its magnetometer instrument, which measures magnetic fields and environments in interstellar space..

If Voyager 1’s power levels drop further, such a drop would trigger an autonomous fault protection system called a low-voltage fault protection system. The system would shut down Voyager’s components, and recovering anything shut down during the automated process would require a long and risky rescue effort by engineers in the field.

“I think of failsafe as a safety net for a trapeze artist – it’s there but actually the trapeze artist should never give up trapeze,” Badaruddin said. “Failsafe puts the spacecraft in a safe state, but we need to recover from that state and ‘get back to the trapeze’.”

Failsafe also temporarily halts the transmission of scientific data from Voyager to Earth, increasing the risk of the science instruments not turning back on properly, he said.

Mission engineers were ready to take action and consulted a list they had compiled years ago with the science team about the order in which they wanted to shut down the various instruments while ensuring Voyager 1 could still conduct a viable science mission.

The Low Energy Charged Particles experiment was at the top of the list. The device has been measuring charged particles such as ions, electrons and cosmic rays from our solar system and the Milky Way galaxy more broadly for nearly 49 years. The measurements provided unprecedented data on regions of varying density beyond the heliosphere.

The device’s subsystems include a telescope and magnetospheric particle analyzer with a 360-degree view thanks to a rotating platform driven by a stepper motor.

Using only 0.5 watts, this little motor will stay on; This means that the device itself could be revived in the future if there is enough power.

The stepper motor has been tested to approximately 250,000 steps on Earth; this was enough to operate during Voyager 1’s flybys of Jupiter and Saturn over a four-year period.

“The Stepper worked flawlessly for approximately 49 years and took more than 8.5 million steps,” Stamatios Krimigis, the device’s principal investigator at the Johns Hopkins Applied Physics Laboratory, wrote in an email. “And surprisingly, after turning off the LECP supplementary heater to save power, it continued to step and its temperature dropped to -62 degrees Celsius.
This is what dreams are made of!

Sign up CNN’s Wonder Theory science newsletter. Explore the universe with news about fascinating discoveries, scientific breakthroughs and more.

For more CNN news and newsletters, create an account at: CNN.com