It's not aurora, it's STEVE
The Strong Thermal Emission Velocity Enhancement, visible as a pink band rising from the lower left to upper right of this photograph, appears with the Milky Way over Childs Lake, Manitoba, Canada. Scientists have recently confirmed STEVE is a unique phenomenon and not a kind of aurora, as previously thought. The picture is a composite of 11 images stitched together. Credit: Krista Trinder and NASA

Aurora-watchers gazing at spectacular displays over the Labor Day weekend may have been seeing more than the northern lights. They may have been dazzled by STEVE as well.

STEVE is short for the Strong Thermal Emissions Velocity Enhancement, a auroral researchers, citizen-scientists and photography enthusiasts first introduced to the world in 2016.

STEVE’s narrow ribbon of light, to the , looks strikingly similar to . However, there are distinct differences. First, its pinkish mauve color is not aurora-like. In addition, the phenomenon is often associated with “picket fence” emissions, which look like green columns of light passing through the ribbons at lower altitudes. Lastly, STEVE appears in areas farther south than auroral lights typically do.

Scientists thought something didn’t add up.

This summer, researchers confirmed that STEVE is not aurora, but is instead a unique phenomenon. Their findings were published in the journal Geophysical Research Letters.

“The big thing is, we can clearly say now it’s not regular aurora,” said University of Alaska Fairbanks researcher Don Hampton, a co-author on the paper. “It’s a new phenomenon, that’s pretty exciting.”

The project, led by University of Calgary researcher D.M. Gillies, used a spectrograph to examine the light from the phenomenon and identify what kind of emissions it gives and in what patterns and wavelengths. Hampton and his colleagues designed and built the spectrograph at the UAF

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