In December, 2005, NASA announced that the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) satellite used to analyze the impact of solar wind on Earth’s magnetosphere, was officially kaput.
Its end was not unexpected. Launched in March, 2000, the satellite’s primary mission was only scheduled for 2 years, but the little orbiter kept sending back data for 5.8 years on an extended mission before the space agency lost its signal. Now, as Paul Voosen at Science reports, an amateur astronomer has locked on to the long-lost IMAGE satellite’s signal, and NASA is hoping to make contact.
Scott Tilley, an amateur radio astronomer with an interest in spy satellites, is the man behind the find. After the classified Zuma satellite went missing in early January, Tilley began investigating high Earth orbit to find signs that the secret satellite made it into space. He didn’t find Zuma, but he did detect a signal from satellite 2000-017A, 26113—the call sign for IMAGE.
Tilley announced his findings on his blog Riddles In the Sky on January 21. Now, Voosen reports, former members of IMAGE science team are hoping the satellite can be contacted and perhaps revived.
As Mike Killian at AmericaSpace reports, since Tilley’s announcement, other amateur sky sleuths have also detected signals from IMAGE. “We’re still not sure it really is IMAGE, but we are working to identify people knowledgeable about the mission after all this time and working on getting all the appropriate scripts and software in-place just in case it is IMAGE," Jeff Hayes, a heliophysics scientist at NASA HQ in DC, writes in an email to AmericaSpace. If the blip does turn out to be IMAGE, NASA hopes to reassemble some of the circa 2000 software used to communicate with the satellite.
According to his blog post, Tilley looked back at his data archives and discovered that he also picked up a signal from the satellite in May 2017. A fellow satellite tracker also examined his archives and found the IMAGE signal clicking in October 2016, but it did not seem to be active in January and February of 2014.
Why did IMAGE go dark in the first place? An analysis by NASA determined an event tripped its Solid State Power Controller, which powers the transponder it uses to communicate with ground control. In other words, it blew a fuse, similar to the failures that shut down two other satellites EO-1 and WMAP. After the trip, due to a design defect, the transponder was not able to power back up. In the analysis, NASA said it was unlikely the mission could be revived.
The last hope was a reboot after what is known as the satellite's “eclipse season,” when the craft lingers in Earth’s shadow, draining its solar-powered batteries. This puts the satellite in a hibernation mode; when it comes out, it reboots. In October 2007, NASA believed it was possible for this reboot to once again power the transponder, but it seemed to fail. As Voosen reports, IMAGE went into an extended eclipse five years ago and again last year. It’s possible that during one of these reboots the transponder regained power.
Patricia Reiff, space plasma physicist at Rice University who was a co-investigator on the mission, tells Voosen that she hopes the satellite comes back online since no current satellite has all of IMAGE's capabilities. In its original press kit, NASA explained that the satellite would give researchers a wide view of particle movements in the magnetosphere and show how the sun interacts with those particles. “It is really invaluable for now-casting space weather and really understanding the global response of the magnetosphere to solar storms,” she tells Voosen.
This is not the first time NASA has found a long-lost satellite. In August, 2016, NASA picked up a signal from the Solar and Terrestrial Relations Observatory: STEREO-B, one of a pair of probes designed to observe solar storms on the sun's surface. NASA expected to lose contact when the satellite transited behind the sun in late 2014, but something went wrong and STEREO-B never phoned home after October 1, 2014. NASA searched for the satellite’s signal every month for almost two years before picking it up. But just a month later, they again lost the signal. According to its last update, NASA has gone back to monthly searches for the craft.
Hopefully IMAGE will be ready for a call home—and engineers can convince it to stay on the line.