NASA confirms it: Voyager has left the solar system

Launched in 1977, spacecraft hurtles into unknown

Pasadena, Calif. — The spacecraft’s technology was laughable by today’s standards: It carried an 8-track tape recorder and computers with 240,000 times less memory than a low-end iPhone. When it left Earth 36 years ago, it was designed as a four-year mission to Saturn, and everything after that was gravy.

But Voyager I has become— unexpectedly— the Little Spacecraft That Could. On Thursday, scientists declared that it had become the first man-made object to exit the solar system, a breathtaking achievement that NASA could only fantasize about back when it was launched in 1977, the same year that “Star Wars” was released.

“I don’t know if it’s in the same league as landing on the moon, but it’s right up there — ‘ Star Trek’ stuff, for sure,” said Donald A. Gurnett, a professor of physics at the University of Iowa and the coauthor of a paper published Thursday in the journal Science about Voyager’s feat. “I mean, consider the distance. It’s hard even for scientists to comprehend.”

Evenamongplanetary scientists, who tend to dream large, the idea that something they built could travel so far for so long and pierce the sun’s reach is an impressive one. Plenty of telescopes gaze at the far parts of the Milky Way, but Voyager 1 can now touch and feel

this unexplored region and send back detailed dispatches. Given the distance, it takes about 17 hours for Voyager’s signals to reach NASA’s Jet Propulsion Laboratory here.

“This is historic stuff, a bit like the first exploration of Earth, and we had to look at the data very, very carefully,” said Edward C. Stone, 77, NASA’s top Voyager expert, who has been working on the project since 1972.

Ever the stoic scientist, he does get excited about what comes next.

“It’s now the start of a whole new mission,” he said.

The lonely probe, which is 11.7 billion miles from Earth and hurtling away at 38,000 mph, has long been on the verge of bursting through the heliosphere, a vast, bullet-shaped bubble of particles blown out by the sun. Scientists have spent this year debating whether it had done so, interpreting the data Voyager sent back in different ways.

But now it’s official: Voyager 1 has passed into the cold, dark and unknown vastness of interstellar space, a place full of dust, plasma and other matter from exploded stars. The article in Science pinpointed when: Aug. 25, 2012.

“This is themomentwe’ve all been waiting for,” Jia-Rui C. Cook, the media liaison at NASA’s Jet Propulsion Laboratory, said in an email to a reporter. “I can’t even sleep it’s so exciting!”

Coincidentally, the same month that Voyager 1 left the solar system, Curiosity, NASA’s state- of- theart rover, landed on Mars and started sending home gorgeous snapshots. Soon afterward, Curiosity’s exploration team, some 400 strong, dazzled the world by driving the $ 2.5 billion robot across a patch of Martian terrain, a feat that turned the Red Bull- chugging engineers and scientists of Building 264 of the Jet Propulsion Laboratory campus into rock stars.

A spoof video, “We’re NASA and We Know It,” recorded to the beat of the song “Sexy And I Know It,” generated 2.8 million views on YouTube.

Voyager, meanwhile, stopped sending home pictures in 1990, to conserve energy. In its heyday, it pumped out never-beforeseen images of Jupiter and Saturn, but lately there has not been much to see.

As the mission lost its sizzle, its 12- person staff was booted from the laboratory’s campus and sent to cramped quarters down the street, next to a McDonald’s. Suzanne R. Dodd, the Voyager project manager, said that when she has attended meetings in Building 264, she has kept a low profile in deference to the Mars team.

“I try to stay out of the elevator and take the stairs,” Dodd said. “They’re doing important work there, and I’ll only slow them down.”

Now she and her team seem poised to be back in the spotlight, perhaps for years to come. Stone, vice provost for special projects at the California Institute of Technology and former director of the Jet Propulsion Laboratory, expects Voyager 1 to keep sending back data— with a 23-watt transmitter, about the equivalent of a refrigerator light bulb — until roughly 2025.