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Not all science is performed by people in white lab coats under fluorescent lights in academic buildings. Sometimes, the course of the scientific record changes forever in a pub over a pint of beer.
Such is the case with the sweeping purple and green lights that can hover above the horizon in the Northern Hemisphere. This phenomenon looks like the aurora borealis but is actually something completely different.
It’s called Steve.
The rare light spectacle has caused as much buzz this year as the sun Entering the most active periodwhich increases the number of dazzling natural phenomena appearing in the night sky – and leads to new reports of people spotting Steve in areas where it normally does not appear, such as parts of the planet Earth. United kingdom.
But about eight years ago, when Elizabeth MacDonald, a space physicist at NASA’s Goddard Space Flight Centre, was in Calgary, Alberta, for a symposium, she had never seen the phenomenon in person before. It didn’t have a name yet.
In fact, a few scientists who study the aurora and other night sky phenomena have witnessed Steve’s appearance Closer to the equator of twilight and is characterized by a pinkish-purple arc accompanied by green vertical stripes.
After MacDonald gave a lecture at a nearby university, she met some citizen scientists — most of them photographers who spend nights hoping to capture the next stunning photo of the colors dancing in the Canadian sky — at a Kilkenny Irish pub.
“I’ve already been communicating with local aurora chasers in Alberta (in) a Facebook group, which was very small at the time, but I’m very keen to share their feedback and interact with NASA,” MacDonald said.
Photographers came with their pictures in hand, eager to show off the mysterious light show they had captured.
Courtesy Neil Zeller
The streak of purple and pink light marking Steve is visible in this photo taken by Canadian photographer Neil Zeller.
At the time, “we didn’t know exactly what it was,” MacDonald said of the phenomenon seen in the photos.
Neil Zeller, a citizen scientist or photoguru — as photographers who chase the aurora are sometimes called — was present at that meeting.
“I started detecting what we used to call the proton arc in 2015,” Zeller said. “It had been photographed in the past, but it had been misidentified, so when I attended that meeting in a Kilkenny pub… we started a bit of an argument about (whether) I had seen the proton arc.”
Dr. Eric Donovan, a professor at the University of Calgary who was at the bar with MacDonald that day, confirmed to Zeller that he had not seen the proton arc, which according to a paper Donovan later co-authored is “subsighted, broad, and diffuse,” whereas Steve’s is “bright.” Visually, tight and organized.”
“And the conclusion of that evening was, ‘We don’t know what this is,'” Zeller said. “But can we stop calling it a proton arc?”
Shortly after that bar meeting, another aurora chaser, Chris Ratzlaff, suggested a name for the mysterious lights on the group’s Facebook page.
The group members were We are working to understand this phenomenon better, but “I suggest we call it Steve until then,” Ratzlaff said books In a Facebook post in February 2016.
The name was borrowed from the 2006 DreamWorks animated film “Over the Hedge,” in which a group of animals become frightened by a towering leafy bush and decide to refer to him as Steve. (“I’m a lot less afraid of Steve,” declares the porcupine.)
The name stuck. Even after this phenomenon can be better explained. Even after Steve’s explanations began to take shape in scientific papers.
Scientists later developed an abbreviation with the name: Strong Thermal Emission Velocity Enhancement.
That meeting in a small Canadian bar was a turning point.
“That in-person meeting was one of the parts that gave it more momentum to eventually collect more and more observations in a more rigorous way where we could correlate that to our satellite,” MacDonald said.
Ultimately, MacDonald said, the satellite monitored Steve directly, collected important data and led to 2018 Stady Which suggests that the lights are a visible manifestation of something called subauroral ion drift, or SAID.
SAID refers to a narrow stream of charged particles in the Earth’s upper atmosphere. MacDonald said researchers already knew that SAID existed, but they didn’t know that it could sometimes be visible.
STEVE is visually different from the aurora borealis, which are caused by electrically charged particles that glow when they interact with the atmosphere and appear as dancing bands of green, blue or red. Steve – if caused by SAID – mostly consists of the same things. But it appears at lower latitudes and appears as a streak of violet-colored light accompanied by distinct green bands, and is often referred to as a picket fence.
Steve can be frustratingly difficult to spot, as he appears alongside the aurora borealis with little regularity. Sometimes, Steve finds out Donna Lash, a photographer based in the Canadian province of Manitoba, pointed out that it is a matter of luck.
Lasch has seen and photographed Steve nearly two dozen times, a rare feat in the world of sky photography. She said she uses her family’s farm on a remote piece of land in southern Manitoba, where there is little light pollution.
Courtesy Donna Lash
Above is a photo of Steve taken by Canadian photographer Donna Lash in 2022.
She always checks the space weather before heading out. It looks for conditions of at least Kp3, a space weather index that ranges from Kp0 to Kp9, with higher numbers indicating more activity.
Lash said the phenomenon appears to start with the SAR — a stable auroral red arc — appearing nearby Crepuscular oval.
“It could eventually migrate southward… toward the equatorial side of the aurora and form STEVE,” Lash said.
Steve will always appear alongside the aurora, but not every aurora includes Steve, Lash and Zeller said.
Where and how to see Steve
The Earth is entering a period Enhancing solar activityOr solar maximum, which occurs every 11 years or so, MacDonald said.
During this time, viewers can expect more visible light displays in the sky, and perhaps the chance to view Steve at lower latitudes. She said light phenomena have been observed as far south as Wyoming and Utah.
“There have been recent storms that have been visible “In the United States — just a little bit — all the way to Death Valley,” MacDonald said. “More recently, the November event was visible far south over Turkey, Greece, Slovakia, and even China, which is very rare.”
Steve is best seen through the camera lens.
Zeller and Lasch note that to the naked eye, it can look like just the faint jet of an airplane streaking across the sky, and can be easy to overlook.
The cameras are more sensitive to light, capturing Steve’s vibrant colors through their lenses.
MacDonald added that even a phone camera can work.
“This is the first solar maximum at which most people’s cell phones can take a good photo of the aurora,” she said.
Steve’s phenomenon is most likely to be captured during the spring and fall equinoxes, according to Zeller and Lash. (This year’s autumn equinox occurred on September 23.)
“I don’t think it’s Steve that occurs more during the equinox, but larger aurora storms are known to occur near the equinoxes,” MacDonald noted. Because STEVE tends to appear alongside the aurora borealis, this phenomenon is most likely to be observed in March or September.
Zeller and Lash said they usually saw Steve between the evening and midnight.
“It’s not an all-night thing,” Zeller said. “The longest I’ve ever seen Steve was an hour from start to finish.”
Zeller added that he waits until the auroral storm begins to fade before pointing his camera eastward — from his vantage point in Canada — or straight up, and then “you start seeing this purple river.”
This is Steve.
MacDonald encourages anyone interested in photographing the aurora borealis — or Steve — to participate in online communities. aurorasaur, a website Which connects photographers with scientists, is a project she said she cares deeply about, noting its critical role in helping scientists formally identify Steve.
She said images contributed by members of the public continually help scientists improve their understanding of these light displays.
“Scientists are not as good at chasing the aurora borealis as the enthusiastic public,” she said. “We don’t stay up all night, and neither do we photographers.”