Mysterious glowing spiral in the sky over Alaska draws questions, and a simple explanation

In the early hours of Saturday morning, Todd Salat was outside near Delta Junction doing he what he does often: directing his camera at the sky, hoping to capture dazzling images of the aurora borealis.

That’s when the Anchorage-based photographer saw something wild — a sudden, bright light on the northern horizon that quickly started to take on a spiral shape as it drew nearer.

“It got bigger and bigger,” Salat said Saturday. “And I had absolutely no idea what it was.”

The whiteish-blue spiral appeared to move quickly. After about five minutes, it was almost overhead, he said.

“It was a beautiful piece of art in the sky,” he said. “I would say this was maybe the most bizarre thing I’ve ever seen in my life.”

Salat, whose work as a photographer specializes in the northern lights — his business name is Aurora Hunter — spent the next two hours taking photos of the dancing auroras, all the while wondering what that spiral was.

Don Hampton, a research associate professor at the University of Alaska Fairbanks Geophysical Institute, said by email Saturday that the spiral “appears to be rocket engine exhaust from a SpaceX Transporter-7 mission that launched on the Falcon 9 about three hours earlier in California.”

“Water vapor in the exhaust from the second stage engine freezes and catches high-altitude sunlight, effectively glowing and creating this spiral galaxy of a display,” Hampton wrote.

As the rocket gained altitude, “it did this pass-by over Alaska, stunning many night-watchers,” he said.

Hundreds of miles away from Salat, midwife Elizabeth Withnall in the Northwest Arctic community of Kotzebue was also outside in the wee hours of Saturday hoping to catch a glimpse of the northern lights, which were forecast to be bright overnight.

She snapped some photos of the spiral when it appeared, and like Salat, she had no idea what she was seeing.

“We get a lot of very unusual phenomena in the sky in the far north,” she said. “I’ve seen fog bows and rainbows around the moon. So I just thought, ‘This is some weird thing in the sky, and I don’t know what it is, but it’s pretty cool.’ ”

She posted a few images of the spiral to a Facebook group that people use to track aurora activity and asked if anyone knew what it was. Dozens responded, and hundreds of people reacted to the strange sight. The most popular explanation: the SpaceX launch involving dozens of satellites.

“Honestly, I’ve never posted anything that got so many hits and comments,” she said.

Later that morning, Salat was able to do some online research too — which turned up the same explanation offered by Hampton and many social media commenters.

He said apparently solving the mystery was not quite as satisfying as seeing the strange phenomenon in the first place.

“The spiral, it was so perfect. It was beautiful. It was kind of a shame to think of it as exhaust, I have to admit,” he said. “I did enjoy that mystery, and the unknown, because after I found out what it was, I noticed that the wonder of it all kind of faded a little bit.”