After 37 years of inactivity, the NASA spacecraft Voyager 1 fired up its thrusters for the first time in nearly four decades all the way over in interstellar space.
This incredible – and unsuspected – triumph means Voyager 1 can once again communicate with Earth, from 13 billion miles away.
Voyager 1, NASA’s farthest and fastest spacecraft, is the only human-made object in interstellar space, the environment between the stars.
Travelling at speeds of more than 35,000 mph, the Voyagers travel about 900,000 miles farther from Earth each day, a distance equal to roughly 36 times Earth’s circumference.
Five years ago, in August 2012, Voyager 1 crossed the edge of the heliosphere, called the heliopause, venturing for the first time into the space between stars, where no spacecraft had gone before.
The spacecraft, which has been flying for 40 years, relies on small devices called thrusters to orient itself so it can communicate with Earth, NASA explained in a statement.
These thrusters fire in tiny pulses, or ‘puffs’ which last mere milliseconds, to subtly rotate the spacecraft so that its antenna points at our planet.
But since 2014, NASA noticed the thrusters aboard Voyager 1 were badly degrading, so propulsion experts at NASA’s Jet Propulsion Laboratory analysed options and predicted how the spacecraft would respond in different scenarios.
The team, made up of Chris Jones, Robert Shotwell, Carl Guernsey and Todd Barber, agreed on an unusual solution: Try giving the job of orientation to a set of thrusters that had been asleep for 37 years.
Jones, chief engineer at JPL, said:
The Voyager flight team dug up decades-old data and examined the software that was coded in an outdated assembler language, to make sure we could safely test the thrusters.
Looking for some hot stuff? I fired backup thrusters for the first time in 37 years, and they worked like a champ. This could extend my life 2-3 years. https://t.co/N0pF3nvOkO pic.twitter.com/V35vMbrHCr
— NASA Voyager (@NASAVoyager) December 2, 2017
On Tuesday, Nov. 28, 2017, Voyager engineers fired up the four thrusters and waited eagerly as the test results traveled through space, taking 19 hours and 35 minutes to reach an antenna in part of NASA’s Deep Space Network, at Goldstone, California.
Amazingly, the test was successful. Now, the Voyager team, based in Pasadena, California, is able to use a set of four backup thrusters, dormant since 1980.
Check one, check one-two. Transmitting live via Madrid dish 63. See spacecraft communicating now via https://t.co/7KefJWr5WA pic.twitter.com/4xgqQQ24li
— NASA Voyager (@NASAVoyager) September 29, 2017
The Voyager team got more excited each time with each milestone in the thruster test.
The mood was one of relief, joy and incredulity after witnessing these well-rested thrusters pick up the baton as if no time had passed at all.
NASA’s Voyager 1 spacecraft launched atop its Titan/Centaur-6 launch vehicle from the Kennedy Space Center Launch Complex in Florida on September 5, 1977, at 8:56 a.m. local time.
Suzanne Dodd, project manager for Voyager at NASA’s Jet Propulsion Laboratory said:
With these thrusters that are still functional after 37 years without use, we will be able to extend the life of the Voyager 1 spacecraft by two to three years.
The thruster test went so well, the team will likely do a similar test on the TCM thrusters for Voyager 2, which is also on course to enter interstellar space, likely within the next few years.
To infinity and beyond!