There’s something new in the dazzling display that is the Northern Lights, and its name is Steve. The astronomical phenomenon was first noticed by enthusiasts over on Facebook, the Alberta Aurora Chasers.
University of Calgary researcher Eric Donovan saw the the photos on the social media platform; the spectacle by then had been called a proton arc. It was not possible, however, as the researcher knew that proton auroras are almost invisible to the naked eye. Further studying showed that Steve is actually a hot and fast flowing ribbon of gas appearing as a purple streak of light slightly above the Earth's atmosphere.
Getting to know Steve
“It turns out that Steve is actually remarkably common, but we hadn’t noticed it before," Donovan reported. A Swarm satellite helmed by the European Space Agency took images of Steve, which Donovan then compared with photos taken from the ground. On why the phenomenon had not been documented before, Donovan said it’s due to limited technology back in the day.
Steve lasts for up to 20 minutes long and appears as an east-west arc, stretching to thousands of kilometeres, and far enough south that residents of northern U.S. states and the southern Prairies may see it. To the naked eye, Steve doesn't exactly look like the picture above. In fact, gazers originally mistook it for the contrails of a plain, because of its faint hue.
With help from slow shutter speeds and photo editing to dial up the color saturation, the Facebook group was able to show the night sky spectacle in its full glory.
How Steve came to be
The typical auroras that are seen in the night sky are caused when energetic particles from the sun collide with air molecules in the upper atmosphere, and transfer some of their energy to those molecules.
The excited air molecules then dump that excess energy in the form of light. Protons are what make the wider arcs that we normally see, while electrons cause thinner auroras like Steve.
While Swarm has paved the way for the better understanding of the Steve phenomenon, ESA’s mission scientist Roger Haagmans said that eagle-eyed citizens are also to be credited.
He added that it was northern lights enthusiasts who triggered scientists’ curiosity, and called the move a “nice example of society for science.”
While visible on Earth, auroras have also been detected and captured on other planets including Jupiter, Saturn and Uranus.
