Several avid northern lights watchers who call themselves Alberta Aurora Chasers on Facebook were sharing photographs at a talk when a professor at the University of Calgary noticed something strange. The citizen scientists were referring to a purple streak of light as a "proton arc," but no proton auroras are actually visible. Intrigued, Prof. Eric Donovan looked into the matter and, looping in other scientists, realized they were observing a previously undescribed night light, reports the BBC. The group of amateurs took to calling the light "Steve," with one joking that it's more than just a nice name but possibly also an acronym for Sudden Thermal Emission from Velocity Enhancement.
Meanwhile, the European Space Agency lined up its Swarm satellite with another Steve sighting to collect data. While the light remains largely a mystery—outside of it not stemming from solar particles interacting with the Earth's magnetic field, as is the case with aurora borealis—Swarm revealed that the temperature of the arc was 5,400 degrees hotter inside the ribbon of gas than outside, and that the ribbon was moving 600 times faster than the air around it. Steve is "actually remarkably common, but we hadn't noticed it before," one ESA scientist says. "It is amazing how a beautiful natural phenomenon, seen by observant citizens, can trigger scientists' curiosity. This is a nice example of society for science." (Tourists in Iceland were caught driving under the influence of the aurora.)