A massive mystery spiral hung in the skies of Alaska last weekend, confusing night sky watchers hoping to catch an aurora instead of aliens.
Alaska-based photographer and "professional aurora hunter" Todd Salat was one of many who caught the surreal sight in a stunning series of pictures. Salat caught a 30-second time-lapse that showed the spiral growing and stretching over Donnelly Dome near Delta Junction, Alaska, on April 15 against the northern lights.
As it turns out, the minutes-long spectacle was more NASA than E.T.
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"At first I had no idea of what I was seeing," he told NBC in an email, "but this phenomenon appears to be caused by engine exhaust from a SpaceX Transporter-7 mission."
The SpaceX rocket launched from California's Vandenberg Space Force hours earlier and the engine exhaust vented water vapor that turned into ice during its fly-by over Alaska.
Don Hampton, a space physicist and professor at the University of Alaska Fairbanks Geophysical Institute, told NBC affiliate KTUU that the ice effectively caught and reflected sunlight from its high altitude, creating “this spiral galaxy of a display.”
Others, like Elizabeth Withnall in Kotzebue, Alaska, were more annoyed than amazed.
"Seriously, Elon?" Withnall posted on social media. "You gotta ruin my aurora?"
This isn't the first flying sky spiral caused by a SpaceX launch this year – one was caught by the Subaru-Asahi Star Camera over the night skies of Hawaii last January from a military GPS satellite that launched from Florida.