A spiral-shaped vortex of light recently appeared in the sky above Alaska, captured by cameras at the University of Alaska’s Poker Flat Research Range. The strange whirlpool was caused by a Falcon 9 rocket launched from California’s Vandenberg Space Force Base, ejecting rocket fuel which became frozen in space and reflected sunlight back to Earth. These spirals, nicknamed «SpaceX spirals,» have become increasingly common as the number of SpaceX launches has risen. Though not every launch creates the spirals, they have been captured by astrophotographers and star cameras around the world.
The spiral spotted on April 15 in Alaska was visible for about seven minutes, as vibrant green Northern Lights were already dancing across the night sky. Todd Salat, an astrophotographer who captured an image of the spiral above Donnelly Dome, initially thought the object was a jet airliner before it took on its spiral shape and grew large quickly.
While SpaceX is a major cause of these rocket-derived light shows, other rocket launches have also created similar displays. In April 2022, frozen fuel from a Chinese rocket created a spinning orb of light that photobombed an auroral display above Alaska. In October 2017, a larger blue orb was seen in the sky above Siberia caused by frozen fuel from Russian military rocket tests.
Despite their increasing prevalence, not every SpaceX launch creates these spirals. They are typically formed when rocket fuel is ejected from the fast-spinning upper stages of Falcon 9 rockets and becomes frozen in space. The frozen swirls then reflect sunlight back towards Earth, creating a visible light display.
While some may confuse these spirals with auroras, they are distinct phenomena. SpaceX spirals are formed by rocket fuel, while auroras are caused by particles from the sun colliding with Earth’s magnetic field.