MYSTERIES OF THE UNIVERSE

Photographers who began taking images of unusual lights in the night sky suddenly found themselves to be citizen scientists

Reported by David Crookes

© Krista Trinder; Getty

For a long time, photographers have been snapping away at the glowing green dancing lights that are often seen in high-latitude regions of our planet’s night sky. Known as aurorae, these light displays attract many thousands of enthusiasts.

But when a growing number of people also began to see a thin purple ribbon of light, interest in this natural celestial phenomenon began to pique even further. Appearing for as little as 20 minutes to as much as an hour, the mysterious purple arcs were reported 30 times across 2015 and 2016, mainly by aurora chasers from Alberta, Canada. And those who had watched the northern lights for many years in this location knew something strange was occurring.

What they were witnessing, they surmised, was a different kind of light show to the ones that they were used to. Unlike a typical aurora which presents itself as an oval of green, blue and red light lasting hours, this phenomenon appeared as a line which extended for hundreds if not thousands of miles. The ribbon of light clearly had a start and end point, and it was often accompanied by an unstable green structure resembling a picket fence-like aurora – a two-for-one light show deal, for want of a better description. “I knew it was rare,” says photographer Neil Zeller, who is among many to have witnessed the purple stream, “but at the time it was simply another neat feature of the night sky.” Even so, as word spread, photographers began to get together to share more information about what they were seeing.

"I KNEW IT WAS RARE, BUT AT THE TIME IT WAS SIMPLY ANOTHER NEAT FEATURE OF THE NIGHT SKY"

NEIL ZELLER

Before long, a Facebook group called Alberta Aurora Chasers was set up to encourage people to post their images and experiences of the natural light display. This became a key focal point for the aurora chasers, who enthusiastically pored over the details being shared while marvelling at what had been captured.

For fun, the group’s lead administrator, Chris Ratzlaff, named the phenomenon STEVE, in reference to the 2006 animated film Over the Hedge in which an unfamiliar shrub is given the same moniker by animals unsure as to what it is. “We also commonly and mistakenly called it a proton arc,” Zeller adds. But it soon transpired that aurorae and STEVE were being caused by different physics. It was no standard aurora, that’s for sure.