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GREENBELT, Md. — Not all science is done by people in lab coats under the fluorescent lights of university buildings. In some cases, informal chats can change the trajectory of the scientific record forever.
The same goes for the purple and green lights that spread across the horizon in the northern hemisphere. Although this phenomenon looks like the aurora borealis, it is actually something else entirely.
My name is Steve.
This unusual light spectacle is making a bit of a splash this year, as the sun enters its most active period and the number of dazzling natural phenomena appearing in the night sky increases.
About eight years ago, when NASA Goddard Space Flight Center astrophysicist Elizabeth McDonald was in Calgary, Canada, for a seminar, she had never seen this phenomenon firsthand. And it didn’t have a name yet.
In fact, Steve, a scientist who actively studies the aurora borealis and other night sky phenomena, spotted a purplish-pink arch with vertical green stripes that appears closer to the equator than the aurora borealis. There were hardly any people.
name the spectacle
At the time, “we didn’t know exactly what it was,” McDonald said of the phenomenon seen in the images.
“I started discovering something called a proton arc in 2015,” said photographer Neil Zeller. “It had been photographed previously but was misidentified, so when I attended the meeting in the Kilkenny pub we started a bit of a debate about whether we had seen a proton arc or not.”
Eric Donovan, a professor at the University of Calgary who was in the pub with MacDonald that day, assured Zeller that he had not seen the proton arc, but a paper later co-authored by Donovan said that the proton arc was “invisible. , and is widespread.” Steve says, “It looks bright, narrow, and solid.”
“And the conclusion that night was, we don’t know what this is,” Zeller said. “But can we stop calling this a proton arc?”
It was shortly after that meeting at the pub that another aurora chaser, Chris Ratzlaff, suggested a name for the mysterious light on the group’s Facebook page.
While group members were working to better understand the phenomenon, “until then, I suggest you call me Steve,” Ratzlaff wrote in a February 2016 Facebook post.
The name was borrowed from the 2006 DreamWorks animated film Over the Hedge. In the film, a herd of animals is frightened by a towering green bush and decides to call it Steve. “I’m less scared of Steve now,” Porcupine says.
The name stuck. Even then, this phenomenon could be better explained. Even after explanations about Steve began to take shape in scientific papers.
Scientists later developed the acronym “Strong Thermal Emission Velocity Enhancement” to accompany its name.
What is Steve?
Steve is visually different from auroras, which are caused by electrically charged particles that interact with the atmosphere and glow, appearing as dancing ribbons of green, blue, or red. However, it appears at lower latitudes, often appearing as a mauve streak of light with a distinctive green band, called a picket fence.
Steve can be frustratingly difficult to find, as he appears with Aurora with little regularity.
Photographer Donna Luck has seen and photographed Steve approximately 24 times, a rare feat in the world of sky photography. She said she uses her family’s farm in a remote area of southern Manitoba with little light pollution.
Luck and Zeller said Steve always appears with aurora borealis, but not every aurora contains Steve.
Where and how to meet Steve
McDonald said Earth is entering a period of solar maximum activity, or solar maximum, which occurs about every 11 years.
During this period, viewers can expect more visible light shows in the sky and potentially a chance to see Steve at lower latitudes. The light phenomenon has been seen as far south as Wyoming and Utah, she said.
According to Zeller and Luck, the Steve phenomenon is most likely to be detected around the spring and fall equinoxes. This year’s autumnal equinox was September 23rd.
“While I don’t think Steve is more likely to occur at the equinox, it is well known that larger aurora storms occur closer to the equinox,” MacDonald noted. Steve also tends to appear together with the Northern Lights, so this phenomenon is more likely to be observed in March or September.
Zeller and Luck said they often meet with Steve in the evening or midnight.
“This is not something you can do overnight,” Zeller said. “The longest I’ve seen Steve play was an hour from start to finish.”
Zeller added that if you wait until the aurora storm begins to weaken and then point your camera east or directly overhead from a vantage point in Canada, “you’ll start to see purple rivers.”
That’s Steve.