Global Courant 2023-04-18 07:55:10
ANCHORAGE, Alaska –
Northern lights enthusiasts got a surprise mixed with the green rays of light dancing in the Alaskan sky: a light baby blue spiral resembling a galaxy appeared amidst the aurora for a few minutes.
The cause of early Saturday morning was something more mundane than an alien invasion or the appearance of a portal to the far reaches of the universe. It was just excess fuel released from a SpaceX rocket launched from California about three hours before the spiral appeared.
Sometimes rockets have fuel that needs to be jettisoned, said space physicist Don Hampton, an associate professor at the University of Alaska’s Fairbanks Geophysical Institute.
“When they do that at high altitudes, that fuel turns to ice,” he said. “And if it happens to be in the sunlight, if you’re on the ground in the dark, you can see it as kind of a big cloud, and sometimes it’s swirly.”
While it’s not a normal occurrence, Hampton said he’s seen such events about three times.
The vortex’s appearance was captured in time-lapse on the Geophysical Institute’s all-sky camera and was widely shared. “It caused a bit of an internet storm with that spiral,” Hampton said.
Photographers out for the Northern Lights show also posted their photos on social media.
The rocket lifted off Friday night from Vandenberg Space Force Base in California with about 25 satellites as payload.
It was a polar launch, making it visible over much of Alaska.
The fuel dump timing was correctly timed for visibility over Alaska. “And we have this really cool looking spiral thing,” he said.
Although it looked like a galaxy passing over Alaska, he assures it wasn’t.
“I can tell you it’s not a galaxy,” he said. “It’s just water vapor reflecting sunlight.”
Another spiral was seen in January, this time over the Big Island of Hawaii. A camera on the top of Mauna Kea, outside Japan’s Subaru Telescope National Astronomical Observatory, captured a spiral swirling through the night sky.
Researchers have said it came from the launch of a military GPS satellite that had previously lifted off on a SpaceX rocket in Florida.
