NASA's Rediscovered IMAGE Satellite Had Been Studying Auroras
It was a satellite signal, to be sure, but Tilley suspected it belonged to IMAGE, a long forgotten NASA satellite that went missing back in 2005, and the space agency just confirmed that he was absolutely right. And better yet, the satellite has still been functioning after all this time.
The fact that it's still operational is great news, because before the fateful day when it suddenly went off the grid and NASA couldn't reestablish contact, IMAGE was crucial for the study of auroras like the northern lights. Its job was to record data about charged particles in near-Earth space, namely our planet's surrounding magnetosphere. And it's many of these charged particle interactions that create the bright auroras in the night sky.
Heck, it's even in the name - IMAGE is short for "Imager for Magnetopause-to-Aurora Global Exploration."
Sun & Space (@NASASun) January 31, 2018
For the five years that it was active, IMAGE had access to several fancy tools that it used to examine Earth's magnetosphere and its "inner bubble," the plasmasphere. By measuring charged particles and using ultraviolet and radio imaging, IMAGE confirmed several near-Earth phenomena that had been predicted but never actually seen by any spacecraft - for example, it picked up a plasmaspheric plume of backwards-flowing plasma particles that had only been theorized to exist.
In a press release, the NASA headquarters' director of planetary science Jim Green (who used to work with IMAGE frequently) reminisced about just how important IMAGE was back in the day:
The IMAGE satellite was launched in 2000, and contact was lost in 2005 until it was detected by an amateur astronomer a few weeks ago. Learn more about this workhouse of #aurora research: https://t.co/CA0vB1GVpW pic.twitter.com/FN7WTmHK2F— NASA Sun & Space (@NASASun) February 3, 2018
It's still not entirely clear how IMAGE lost contact back in 2005, but the space agency suspects that some sort of high energy cosmic ray or radiation belt particle might have tripped the satellite's power source. NASA tried to reboot the satellite a couple times to see if they might find it again, but they were unsuccessful - or so they thought. At some point, IMAGE did reboot successfully, and is still functioning even if nobody knew until now.
Which means it's very likely the aurora research may continue in some form, which is good news for any fans of the aurora borealis.