A speeding star and its tail

The GALEX spacecraft took many iconic images during its 10-year career, such as this one of a speeding star and its comet-like tail. (NASA / JPL-Caltech / June 28, 2013)

One of NASA’s prize workhorses, the spacecraft Galaxy Evolution Explorer, or GALEX, was decommissioned Friday after 10 years of scanning the universe in ultraviolet light.

“It had a long run,” said Karl Forster, GALEX science operations center team leader.

The satellite, only 6 feet tall and a svelte 1,034 pounds, was part of NASA’s small Explorer mission. Its main objective was to use ultraviolet cameras to take images of young stars, which are invisible to human eyes because they emit only UV light. It was the first satellite specifically designed to take UV images.

From its perch 404 miles above Earth, GALEX would complete 15 orbits per day, waiting for the planet to block out the sun so it could snap pictures of distant stars and galaxies. With its wide field of view, GALEX could take images the width of two full moons.

The satellite had incredible range. It could reach 80% of the way back to the beginning of time, capturing images of stars being formed as far back as 10 billion years ago.

PHOTOS: Amazing images from space

Originally slated for a 2-year run, GALEX refused to quit. Four times it was given a 2-year renewal, making it the Jamie Moyer of spacecraft. Even after losing one of its UV cameras in 2006, it kept on shooting, with the imagery from the lone camera even improving over time.

While panning the sky, it captured such astronomical wonders as a black hole eating a star and the formation of huge rings of new stars around the remains of dead galaxies.

When it came up for renewal a fifth time in 2011, the old veteran seemed finished. There were newer, sleeker spacecraft hungry for launch, and GALEX had already far exceeded expectations.

Enamored with the gobs of data GALEX produced, Caltech professor and mission leader Chris Martin intervened, offering to keep it alive for another year with his own research money. The hands of time were pushed back, and GALEX continued operating.  

But on Friday the clock struck midnight. Forster and his team uploaded and transmitted code to the satellite that would scramble its wiring, effectively putting the robot to sleep.

Despite the mileage, GALEX could have gone another 60 years, Forster said. Perhaps in headier financial times it would have. Instead, it will silently circle Earth for another 65 years before falling and burning up while reentering the atmosphere.

“GALEX was a constant presence in my life,” Forster told the Los Angeles Times. “Every day I saw the data coming down, I saw that it got processed, and each week I was in charge of making sure the commands that went up were the ones that would execute the science program.”

“My oldest daughter was born about a month before the GALEX launch,” he added. “It’s kind of gone step-by-step with her. It’s amazing to think that that part of my life has come to a close now.”

And so, cue up the final scene of Armageddon, and bid farewell to a great American robot.

Return to Science Now.

brad.balukjian@latimes.com

Twitter/@BradBalukjian