Aurora borealis — and Steve — explained
A new episode of The Nature of Things airing Sunday features University of Calgary researchers and Calgary members of the Alberta Aurora Chasers Facebook group.
The episode, which was filmed outside of Yellowknife, is titled The Wonder of the Northern Lights and “explains it all” when it comes to auroras borealis, including “Steve,” a newly discovered, aurora-related, night-sky phenomenon that went viral in 2017.
“Oftentimes it’s reported that the Earth’s magnetic field traps electrons from the sun and they spiral down the magnetic poles and they cause light,” says Eric Donovan, a U of C professor in physics and astronomy and codirector of the Aurora Imaging Group. “That’s the kind of pithy explanation of the aurora that you find in books and in media. It’s not true, it’s not right. It’s completely wrong, actually.”
Donovan studies the magnetosphere, a windsock-shaped region of space around the Earth that is created when the solar wind interacts with Earth’s magnetic field. It is particles and processes there that create auroras borealis. “People like to say I study the aurora, but I don’t really,” he says. “I’m a magnetospheric guy and the aurora is my instrument. And the cameras are the way I read the data off my instrument.”
Donovan is one of three U of C researchers featured in the TV episode, which also features the Alberta Aurora Chasers, a Facebook group of amateur photographers and enthusiasts. It was a meeting between the chasers and Donovan that led to the viral discovery of the night-sky phenomenon titled Steve.
“It’s a new night-sky phenomenon that amateur night sky watchers and photographers knew about, but we didn’t,” says Donovan.
“We weren’t the first to see the phenomenon,” adds Chris Ratzlaff, one of the co-founders of the now nearly 19,000-strong Alberta Aurora Chasers. “It was seen around the world for years, decades, probably centuries. What we did is help the scientific community recognize it.”
Donovan met with members of the Alberta Aurora Chasers group, including Ratzlaff, after attending a 2016 talk by a NASA scientist in Calgary. The chasers showed pictures to Donovan of a bright, purple streak of light in the sky they had seen during aurora sightings, which they called “the proton arc.” Donovan convinced them it wasn’t a good name, so Ratzlaff came up with the name Steve as a reference to the movie Over the Hedge.
A few months later, Steve came to the attention of the European Space Agency after Donovan gave a weekend presentation about it in Banff.
The ESA wrote a news release, and by Monday Donovan was on the BBC talking about Steve.
“Within a week, my full-time job for three weeks was doing interviews,” says Donovan, who is still researching what causes Steve. “It was viral.”
The episode also promises to answer questions about the connections between aurora and the possibility of extraterrestrial life, the 2003 super solar storm and the role auroras play in the culture of the Indigenous people of Canada’s north.
The episode will be broadcast on CBC on Sunday at 8 p.m. and will also be available online at cbc.ca/ watch and the CBC app on Friday starting at 10 a.m.