Remember the old Sears commercials where their Diehard batteries would start a car in the worst winter weather imaginable?
The Voyager 1 spacecraft makes this look like kid stuff. This diehard is still working in temperatures of -454.81 degrees Fahrenheit, or minus 270.45 degrees Celsius.
Deep space can be like that. Unforgiving. After all, Voyager 1 left Earth in 1977 and is now 15 billion miles. Light from the sun takes 22 hours, 50 minutes and 23 seconds to reach it.
After remaining dormant for 37 years, its thrusters were recently called on to come back to life in order to make critical changes in its trajectory as it continues to go “where no man (or spacecraft) has gone before.”
What does this have to do with Washington State and its amazing space industry? The thrusters were made by Aerojet Rocketdyne in Redmond (it was just Aerojet back then). Since the dawn of the space race, the company has made more than 20,000 propulsion units for nearly any space mission you can think of.
But we’re getting ahead of ourselves. Voyager 1 and its sibling Voyager 2 were designed to travel beyond the reaches of our solar system. They were launched back when disco was still a thing. They are so ancient, that the voice recordings capturing life on Earth that were onboard were stored as an 8-track. For all those younger readers out there, that technology predates digital streaming, iPods, CDs and cassettes.
Back to the mission. No one really knew how long the mission would last, given the challenging and unknown conditions of deep space in the 1970s. Voyager has even gone quiet a time or two, leaving mission managers to wonder if it had simply run out of time, power, or into an unknown space object.
The course correction was needed to keep the spacecraft’s antenna pointed back toward Earth. Without that precise maneuver, Voyager 1 would no longer be able to hear or respond to commands.
The thrusters, of course, hadn’t been called on to do any significant course work since Voyager 1 passed Saturn. Without any use, the thrusters started to become clogged with silicon dioxide, which is a byproduct of an aging rubber diaphragm lining the fuel tank.
It’s not lot like there’s a gas station nearby to have it looked at. The spacecraft doesn’t have enough power to run everything at once, so the engineers had to figure out a way to shut power off to the instrument packages and heat the thrusters a little at a time to clear them out.
Imagine leaving your car in the garage for almost 40 years and trying to start it. Even with a new Diehard, that’s a tall order. But those Washington-made thrusters started right up. All four of them.
“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,” said Suzanne Dodd, project manager for Voyager at NASA’s Jet Propulsion Laboratory, Pasadena, California.
Amazing stuff. But it was more technically challenging than just starting up the thrusters. A lot has changed in nearly 50 years. The software used to test the thrusters was written in what is now an archaic software assembler language. Plus, with Voyager 1 billions of miles beyond Earth, every test the team ran took 19 ½ hours as the signal traveled out to the spacecraft and a confirmation came back to an antenna in California that is part of NASA’s Deep Space Network.
Long story short, Voyager 1 is back on course, thanks to a bunch of thrusters that left the Aerojet Rocketdyne factory when Jimmy Carter was still president.
Space has never been simple, but at times, it has been awe-inspiring.