A group of “Aurora Chasers” in Canada appear to have stumbled on an extraordinary new astrophysical phenomenon, and—in typical internet fashion—endowed it with an amusingly ordinary name. Don’t let the unassuming moniker fool you, though: Steve is a mind-bogglingly powerful event, albeit one that is apparently more common than scientists expected.
|The stream of purple light arcing across the image is no ordinary aurora: meet “Steve”.
Image Credit: ESA
While the phenomenon has been repeatedly spotted during aurora events, suggesting it’s related to solar wind activity, the term “aurora” refers specifically to light generated by the interaction of solar wind particles with the atmosphere. But that’s not what’s going on here: Members of the group that discovered it originally referred to the bright streak as a “proton aurora”, assuming it was similar in origin to the usual shimmering green glow created by electrons interacting with air. However, when protons slam into the atmosphere, they create light that’s much too high-energy to be seen with the naked eye. Steve had to be something else.
Steve is also much higher than most aurorae—close to 200 miles above Earth’s surface. The edge of the atmosphere, although it’s not a hard-and-fast line, is about 60 miles up, although the most powerful of aurorae have been observed to reach as far as 600 miles into space.
P.S. The name “Steve” appears to have been inspired by this scene from the Dreamworks film “Over the Hedge”