Why this solar storm was so monumental, and other things to know about the light show
Dazzling aurora borealis showed power of smartphones, while shedding light on more ‘fundamental questions’
The promised northern lights over the weekend did not disappoint, producing a dazzling light show across Canada and around the world.
Social media platforms were filled with hues of purple, green, yellow and pink skies in Canada, the United States, England, Switzerland and beyond.
CBC News spoke to experts about what transpired, and why it was even more dramatic than expected — especially when seen on your phone.
Why was it so powerful?
As you may have heard by now, the sun is near the end of what's called a solar maximum, an 11-year cycle where it's more active, producing plenty of sunspots on its surface. These sunspots are an entanglement of magnetic fields that can sometimes erupt with a solar flare.
The sun produced a series of strong solar flares last week, resulting in at least seven outbursts of plasma, according to the U.S. National Oceanic and Atmospheric Administration.
Each eruption, known as a coronal mass ejection (CME), can contain billions of tonnes of plasma from the sun's outer atmosphere. In this case, the CMEs headed toward Earth and arrived around the same time, enhancing the power of the geomagnetic storm on Friday and through the weekend.
The NOAA declared a G5 magnetic storm on Friday, one that was even stronger than expected and the highest level since 2003.
"I think the intensity surprised a lot of people," said Trevor Kjorlien, a Montreal-based space educator who runs the company Plateau Astro.
Such events are difficult to predict ahead of time, given the distance involved and all the variables considered, said Nikhil Arora, an astrophysicist and postdoctoral researcher at Queen's University.
"It's a very chaotic process. It can't perfectly predict how much material is actually going to reach Earth," he said. "So it ended up being a bigger one than we previously thought."
Why did it look clearer on my phone?
Many night sky enthusiasts reported seeing the northern lights more clearly on their phone or camera than with the naked eye. The reason for that is simple, said Arora.
"Your phone is actually collecting light for a longer time than your eyes do," he said.
"For our eyes, the collection time is very, very small, and so very dim things don't come out as clearly to us."
Kjorlien noted that this most recent event was the first time where people were equipped with a smartphone camera capable of capturing the northern lights in all their glory.
"That, to me, is a really, really cool thing, that this is ... probably the most photographed northern lights spectacle that we've seen," he said.
I missed it. When will I get another chance?
These events aren't quite as rare as the full solar eclipse that captivated many Canadians last month.
The solar maximum is expected to continue through the end of 2025, Arora said, which means the northern lights could soon be visible in more southern parts of Canada.
Arora himself wasn't able to see the northern lights this time around, given the cloud cover in Kingston, Ont.
He said a trip to Yellowknife, where during the winter months the northern lights are even more dazzling, is "on my bucket list."
Did it lead to any disruptions?
There had been concern the geomagnetic storm could lead to disruptions of satellites and communications equipment.
In some cases, farmers reportedly had to halt planting because of problems with self-driving tractors, which rely on GPS satellites.
But overall, there were no major problems, said Arora.
"Our satellites and our electronics are a lot better protected than they used to be."
Arora said the event will be studied to better understand the Earth's magnetic field — and the universe beyond.
"It's actually hugely important in better understanding planets in our solar system, and also the sun, as well," he said.
"Within astrophysics, one of the biggest questions is: Why does our solar system, or our galaxy — or, more in general, our universe — look the way it does?
"So understanding these little details and better understanding these phenomena sheds light onto the fundamental questions of the universe."
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With files from The Associated Press
