Gazing skywards on a warm summer’s night in the Canadian Prairies four years ago, the significance of what amateur astronomer Chris Ratzlaff had just witnessed wasn’t immediately obvious.
The 45-year-old grew up beyond the bright lights of the cosmopolitan western Canadian city of Calgary and remembers being enchanted by the greenish glow of the wondrous Aurora Borealis illuminating the night sky, but this appeared to be something slightly different.
He initially mistook the mysterious celestial phenomenon – that would later be christened Steve (Strong Thermal Emission Velocity Enhancement) and pique the interest of Nasa scientists – for an irregular plane contrail reaching from the eastern horizon to the western horizon.
“When I took a long exposure photo of it I saw that it was emitting light and knew it wasn’t a contrail,” he recalled to The Telegraph.
“Our community wasn’t familiar with it, and I spent the next few days reaching out to other aurora chasing communities, eventually hearing that others had seen the same thing with rarity over the years and were calling it a proton arc.”
Ratzlaff relayed this information to fellow aurora enthusiasts on the Alberta Aurora Chasers Facebook group, a community he’s nurtured since 2012, to discuss upcoming events that would swell from just a few hundred members to a 16,000-plus community of fervid stargazers over the coming years.
“As our community grew, we had more people watching the skies and saw more reports of people seeing it,” he explains. “But it wasn’t until 2016 that we realised this was a phenomena undocumented by science.”
After discussing the photos with experts Eric Donovan, an astronomy professor from the University of Calgary, and Nasa’s Dr Liz MacDonald at a networking event, the group discovered by chance they had misidentified the mystery purple lights.
#STEVE's motion last night, around 07:30UTC, seen looking WNW over Crossfield, AB. Real-time span was 30 minutes.@TweetAurora @spaceyliz @EdonovanF #SuddenThermalEmissionVelocityEnhancement#aurora #yyc pic.twitter.com/OetRarMph4
— Chris Ratzlaff (@ratzlaff) March 10, 2018
“One of our members was showing them some of his photos, when a photo of the phenomena caught Eric’s eye,” he says. “He explained that this narrow, sculpted, pink thing couldn’t possibly be proton-based.
“I explained to him that our community sees this thing often and we began to collaborate on how to leverage the small army of citizen scientists available through the Alberta Aurora Chasers Facebook page.”
They began working closely with the experts to track the unusual auroral display by sharing reports and photos on the Facebook group, whimsically proposing the name Steve for the colourful narrow arc, which just happened to stick.
Ratzlaff, a software product development manager by day, is just one of a team of citizen scientists – people who are passionate about science but don’t necessarily have a formal qualification in the field – who played a “significant role” in solving the aurora mystery through their meticulous documentation.
“We represent a significant number of experienced night-sky photographers, living in an area of the planet that Steve likes to frequent,” he says.
“We love networking with experts, leading to our meeting with Eric and Liz, and bringing Steve to their attention.
“Our community is very focused on detailed and accurate reporting of our observations, offering experts a high degree of confidence in what we say we saw.”
Tracking Steve has now grown into an international citizen science project called Aurorasaurus which is funded by Nasa, with the space agency asking for the public’s help so they can learn more about how the earth’s magnetic fields function and interact with charged particles in space.
How to spot Steve
A proud Ratzlaff says it’s “pretty staggering and awe-inspiring” for the entire community to have played such a large role in helping solve the mystery of the unusual aurora which has also been sighted in the UK, Alaska, northern US states and New Zealand.
He added: “It’s heartwarming to see so many people taking an interest in not only the aurora, but also citizen science in general, realising that it’s possible for non-scientists to make significant contributions to science.”
Dr MacDonald, a space scientist at Nasa’s Goddard Space Flight Center in Maryland, admitted they “didn’t know what it was” at first.
“It’s really exciting that people armed with cameras all over the globe can capture something we didn’t fully understand and shed new light on that,” she added.