“As this glowing vortex rapidly grew toward me, I thought, what the heck?!?!,” wrote Salat, an experienced aurora hunter. His website. He frantically photographed the strange vortex until it disappeared seven minutes later. Other skywatchers also took pictures of the northern lights without a background. Captured by the University of Alaska’s all-sky camera lack of time of the event.
Guilty? The Falcon 9 vehicle was launched by SpaceX three hours earlier from California. Researchers say such patterns have increased with commercial satellite launches in recent years.
Chris Combs, an aerospace engineer and assistant professor at the University of Texas at San Antonio, said: “It’s interesting to see that it’s definitely not a UFO…it’s just SpaceX.” “It’s not just restricted to SpaceX, but we’re starting to see it more often as they launch more often.”
Researchers say the phenomenon may have been caused by excess fuel released during launch. Steam or other gases in the engine exhaust can freeze at high altitudes, forming ice crystals. Ice crystals reflect sunlight from space, which we can see from the ground.
The spiral shape is created as the rocket spins — like “water from a spinning sprinkler head,” said Carlos Martinez, an aerophysicist at Boston University.
Falcon 9’s second stage may have ejected fuel as it moves to safely descend into orbit, space physicist Don Hampton said. The first stage, or the lowest part of the system, is responsible for lifting the rocket off the ground and returning it to Earth. The Phase II Division A rocket launch delivers the payload into orbit, in this case 51 satellites. The second stage also burns in the atmosphere and uses a de-orbit burn to reorient itself so it can be disposed of safely, such as over the ocean.
Hampton, an associate professor at the Institute of Geophysics at the University of Alaska at Fairbanks, said in an email that “it would take a motor burn to slow it down, and then many would dump their remaining fuel.” “What we saw was rocket exhaust or a fuel dump – I can’t be sure without confirmation from SpaceX.”
It doesn’t take much material to create such a bright-looking cloud, he added. The amount of sunlight-reflecting material can be measured in pounds, not hundreds, he said.
“You can see that it spreads out very quickly, so after a few orbits the concentration goes to zero,” Hampton said. “In sunlight at those altitudes, any complex molecules are broken down into block atoms and simpler molecules by the ultraviolet wavelengths in sunlight.”
Most large rocket launches produce a similar cloud, but due to geography and timing it is very rare to observe it. The exhaust or fuel should be exposed to sunlight, and the ground should be dark. Hampton, who slept through the event and saw the lapse of time captured by his department’s all-sky camera, said clear skies in Fairbanks Saturday morning also allowed for a better view.
“What’s really unique about it is that it has the northern lights behind it, which is really cool,” Combs said.
Previous rocket launches have been associated with unusual shapes, including spirals. A Japanese
At the moment, the rocket-propelled vortex doesn’t have a name, although Combs said, “We might have one at this point.”
“I think it’s very unusual, but with the commercial launch industry and SpaceX launching more, we’re starting to see it a lot more,” Combs said.