This bright purple ribbon-named STEVE-is an entirely new celestial phenomenon

  • This bright purple ribbon-named STEVE-is an entirely new celestial phenomenon

This bright purple ribbon-named STEVE-is an entirely new celestial phenomenon

When scientists first looked at images of STEVE, they realized the lights were slightly different than light from typical auroras but were not sure what underlying mechanism was causing them.

"Probably the most important question to answer now is: if Steve is not produced by precipitating particles (like aurora), how is the structure being created?"

These days, there are "more than 100" of those opportunities a night, and when a Swarm satellite was in the right place at the right time, it recorded STEVE as responsible for the temperature 300km above Earth jumping by 3000°C. But a new study conducted by the researchers from the Universtiy of Calgary, also involved in the research carried out earlier this year, found that the mysterious Steve is not an aurora.

STEVE consists of ribbons of purple and white light.

Scientists plan to continue research and to test whether the phenomenon due to a flow consisting of fast ions and electrons with high energy in the ionosphere. The Alberta Aurora Chasers, that even formed a Facebook group for tracking the aurora lights, named the new type of Aurora STEVE.

Studying STEVE can help scientists better understand the upper atmosphere and the processes generating light in the sky, according to the authors. The display looks different compared to the original polar lights that we see in the northern sky, shown in those lovely Instagram photos.

However, in the new scientific work, researchers have shown that "Steve" is of different nature.

An aurora is generated by solar winds, which interact with charged particles in our magnetosphere, mainly protons and electrons.

The displays light up when electrically charged particles from the sun enter the Earth's atmosphere. The polar lights are usually green, although they sometimes appear to be red or blue.

"The aurora you see in the sky, at least from our data, is moving at a certain speed, and then you have [Steve] moving insane fast at lower latitudes, passing from east to west, super narrow, nearly like a comet", explained Bea Gallardo-Lacourt from the University of Calgary and the study's leading author. The analysis showed that STEVE's light isn't produced by particles raining down into the ionosphere, as typically happens with the aurora.

The researchers chose to focus on a STEVE event in March 2008, which was recorded using both ground-based cameras created to track auroras but also NOAA's Polar Orbiting Environmental Satellite 17, which was directly overhead at the time.

This instrument detected no such particles.

Steve is not an aurora - Then what is it?
"So right now, we know very little about it".

Canada-based photographer Chris Ratzlaff is thought to be behind the Steve nickname, borrowing from the 2006 animated film Over the Hedge, in which characters refer to "the unknown" as "Steve."