Rick Burley couldn’t believe what he was reading.

The email on his computer screen, forwarded by his former colleague Jim Burch, was from someone named Scott Tilley. Tilley, an amateur astronomer in British Columbia, recently had been searching the skies for a signal from the Zuma satellite, a top-secret government mission that many believe failed after Zuma was launched into orbit last month. His radio equipment detected a new signal, but it wasn’t from Zuma. The signal, Tilley believed, came from a long-lost NASA spacecraft that mysteriously went silent without warning 13 years ago—and was never heard from again.

Burley had worked on that mission. It was called IMAGE: Imager for Magnetopause-to-Aurora Global Exploration. NASA launched the spacecraft in March 2000 to study the Earth’s magnetosphere, a region of charged particles trapped by the planet’s magnetic field and battered by solar winds. “IMAGE, as its name indicates, was about imaging the Earth’s magnetosphere and near-Earth environment in combinations of different ways that we’d never done before,” said the former IMAGE scientist Jim Spann, now the chief scientist at the science and technology office of NASA’s Marshall Spaceflight Center.

Using precise measurements, IMAGE visualized, among other things, what happens when particles from the sun come crashing into the magnetosphere and produce dancing auroras in the night sky. It created a complete picture, for the first time, of Earth’s invisible force field.

And it did a good job of it, too, until suddenly, in December 2005, IMAGE stopped talking to Earth. NASA tried and tried to regain contact but heard nothing. The magnetosphere’s best photographer was finished.

Within hours, the email that stunned Burley reached many of the members of the old team. Burley was charged with leading the effort to confirm whether this signal was, indeed, coming from IMAGE. A few hours in, he dashed off a quick note to the growing email chain. “Status of activities taken today,” Burley wrote. “I’ve managed to clean all the coffee off of my laptop that I spit on it when I saw Jim Burch’s email this morning.”

Burley and others from the original IMAGE team rummaged for the documents that guided the spacecraft’s operations years ago. The software they’d used back then now seemed hopelessly out of date, and they scrambled to adapt it to modern versions. “One of my colleagues said he’s dusting off some old computers and seeing if he has the passwords to turn them on,” said Stephen Fuselier, who worked as a coinvestigator on IMAGE’s imaging instruments. Fuselier, a plasma physicist, is now the executive director of the Southwest Research Institute in Texas. At the same time, other astronomers, hearing about IMAGE’s reawakening, volunteered to point radio telescopes toward the direction of the pings Tilley had recorded from his home in Canada.

They had confirmation within days. Last Tuesday, the Johns Hopkins Applied Physics Lab in Maryland detected signals at the same kind of frequency IMAGE used to broadcast. When they dissected the incoming data, they managed to uncover the unique identification number embedded within, like the license plate of a car. The ID was a match. IMAGE was back.

By Friday, Burley and the team had analyzed enough data to determine that IMAGE was up and running again. “So far, IMAGE appears to be operating as designed,” Burley said.

Right now, the team is just listening. Soon, they will try sending commands.

The reappearance of IMAGE has been exhilarating for its former stewards. In the years since its presumed demise, mission members have moved on to different roles, other departments, new missions. The work behind IMAGE lurked at the edges of their memory, remembered fondly but infrequently. Spann said receiving the first batch of data, or achieving “first light,” felt, in a way, like the birth of a child. “You work so hard for so many years, laboring to build this instrument, making sure it’s designed correctly, that it operates well, that it will be safe in the space environment,” he said. “So when you first get data from it ... you’re now going to enjoy the life of this new instrument with all the data that you dreamed of and hoped that it would provide.”

IMAGE proved so successful that NASA agreed in 2002 to extended the mission for two more years. When the spacecraft ceased communicating, “it was a shock,” said Thom Moore, the project scientist for IMAGE. “Just poof.”

About a year after IMAGE went silent—and about the same time that funding for the mission began to run out—NASA released a probable autopsy report for the mission. Spacecraft in Earth’s orbit are constantly bombarded with cosmic rays from the universe. Investigators determined that crucial hardware likely experienced a very direct, very unlucky hit that caused the entire spacecraft to shut down.

In 2007, the IMAGE team had hope that their beloved spacecraft might come back to life. There was a solar eclipse that year that could, in theory, reawaken the machine. IMAGE was designed to reset its computers when its solar-powered battery drained enough. Patricia Reiff, another IMAGE coinvestigator and a space plasma physicist at Rice University, likened the procedure to turning a malfunctioning computer off and on again. “The easiest thing to try when your computer goes bonkers on you is to pull the plug and put it back in and hope it boots back up,” Reiff said. They hoped that some time in Earth’s shadow would be enough to do the trick.

But IMAGE emerged from the darkness as silent as it entered. The mission was formally declared dead. “You really have to say, okay, we had a really great run,” recalls Jim Green, who served as the deputy project scientist for IMAGE and now runs NASA’s planetary science division. “You just gotta pick yourself up and go on.”

It’s not yet clear why IMAGE woke up. NASA said Friday the spacecraft appears to have partially rebooted in November 2004. The latest data shows power is fully restored.

The hope is that IMAGE may be able to conduct observations anew. It’s possible that years of exposure to space radiation have damaged the instruments of the spacecraft, which wasn’t designed to protect itself from the extreme environment for that long. If the tools are healthy, NASA headquarters must determine whether the agency wants to move some money around an already tight budget to fund the effort. Operating a spacecraft—even a zombie one—costs money, after all.

Even then, there’s no guarantee IMAGE will stay online. “If we do recover, we will still be vulnerable to the anomaly that took us out for 13 years,” Burley said.

For now, the old gang is back together again, exchanging news with plenty of exclamation marks over email. They’re thrilled, but they’re not getting their hopes up—at least not too much. IMAGE may have called home, but its future is uncertain, said Jim Burch, IMAGE’s principal investigator, the director of the Southwest Research Institute, and the scientist Tilley first emailed with the big news.

“I learned a long time ago, my hopes are irrelevant,” Burch said. “It turns out how it turns out, right?”