This one was fun to write, partly because the naming of this phenomenon is one of my favorite stories. If you’ve ever seen the 2006 movie “Over the Hedge” you might remember the scene where the animals first encounter the big, scary hedge. To make it less scary, they name it Steve. Now fast-forward to 2016, when some amateur astronomers in northern Canada spotted a new, unknown type of aurora. For lack of a better name, they called it “Steve” in the spirit of the 2006 movie.
Now, STEVE stands for Strong Thermal Emission Velocity Enhancement. That’s a lot of words that probably don’t mean much, but over the past two years we’ve come to realize that STEVE isn’t actually a typical aurora. Instead, it’s something called a “subauroral ion drift”, or SAID. SAIDs are usually produced during auroral storms, but instead of arising from interactions of the solar wind with Earth’s magnetic field, they are short-lived events produced by supersonic flows of ions and plasma in the atmosphere.
STEVE is really cool, and also has a pretty cool name. Go read the post and let me know what you think!
[Image is of STEVE, a long and skinny purple ribbon in the sky, usually southward of the main aurora (Credit: Elfie Hall)]