by Michael D’estries: Aurora enthusiasts first documented the ribbon of light last year…
If you happen to see a vertical ribbon of dancing, flickering light playing across the sky of the northern hemisphere, fear not. It’s just Steve.
That’s right — Steve. The hilarious placeholder name comes from the Alberta Aurora Chasers, a group of aurora enthusiasts who discovered the atmospheric phenomena last year. Unlike your standard aurora displays, which look like gently wafting curtains, Steve is more of a narrow arc of light.
The members settled on the unusual name in honor of the 2006 animated film “Over the Hedge,” in which some woodland creatures name an unknown object “Steve” to make it appear less frightening.
As you can see in the photos below, Steve isn’t at all frightening; it’s just plain beautiful.
An image of Steve captured over Kelowana, British Columbia. (Photo: Uzair Shahid/Alberta Aurora Chasers)
A vertical ribbon of aurora light, nicknamed Steve, captured over Vancouver, British Columbia. (Photo: Vanexus Photography)
So what exactly is Steve? At first, everyone assumed it must be a “proton arc,” but that aurora phenomenon is brightest in the UV part of the spectrum and invisible to the human eye. Physicist Eric Donovan from the University of Calgary in Canada, after spotting some of the unusual photos taken by the Alberta Aurora Chasers, decided that Steve must be something completely new.
To investigate the phenomena, Donovan combed over data captured by a trio of ESA satellites called Swarm. Located in two different polar orbits, the three satellites are constantly recording measurements of the strength, direction and variations of the Earth’s magnetic field. To Donovan’s delight, one of the satellites recently passed through a visit by Steve and captured its unique characteristics.
“The temperature 300 km above Earth’s surface jumped by 3000°C and the data revealed a 25 km-wide (15.5-mile) ribbon of gas flowing westwards at about 6 km/s compared to a speed of about 10 m/s either side of the ribbon,” he said in an ESA press statement.
Speaking with Gizmodo, Donovan says that while he and his colleague have an idea of what might be causing Steve, they’re keeping a lid on their theory until a paper is published later this year. Until then, the physicist says the most surprising thing about the phenomenon is how frequently it occurs.
“It turns out that Steve is actually remarkably common, but we hadn’t noticed it before,” he added. “It’s thanks to ground-based observations, satellites, today’s explosion of access to data and an army of citizen scientists joining forces to document it.”