Dying SpaceX rocket triggers giant spiral of light above UK and Europe during secret mission

On Monday (March 24), a giant swirl of light was spotted floating across the night sky in Europe like an ethereal whirlpool. The baffling light show wasn't caused by aliens, as some speculated, but a dying SpaceX rocket preparing to crash back to Earth, shortly after deploying secret cargo into orbit around our planet.

At around 8 p.m. local time (4 p.m. ET), people across the U.K. reported seeing the luminous swirl grow as it slowly streaked across the sky like something from a sci-fi movie, according to the BBC. The light show was most clearly visible above parts of England, including Lincolnshire, Yorkshire, Leicestershire, Suffolk and Essex, as well as in Wales and further afield in Sweden, Croatia, Poland, and Hungary.

Photographer Simon Minnican captured the ethereal scene in a stunning video that showed a bright spot appear and then grow in size before swelling into an ever-expanding vortex. The entire spectacle lasted around 12 minutes, with the spiral of light dissipating roughly 4 minutes after it unfurled.

There was initially some wild speculation about what had caused the unusual light show, with at least one observer blaming UFOs. However, experts quickly pointed out that it was a "SpaceX spiral" — an increasingly common phenomenon triggered by light reflecting off rocket fuel dumped into space by spinning SpaceX rockets before they reenter Earth's atmosphere.

In this case, the spacecraft responsible for the luminous swirl was a Falcon 9 rocket that had launched from the Cape Canaveral Space Force Station in Florida at 1:48 p.m. ET, more than 4,000 miles (6,400 kilometers) from where the bright spiral was later spotted. This rocket was carrying a secret payload for the National Reconnaissance Office, according to Live Science's sister site Space.com.

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SpaceX spirals occur when the second stage of a Falcon 9 rocket de-orbits and prepares to reenter Earth's atmosphere, where it either burns up or falls into the ocean. During this maneuver, the spacecraft dumps its remaining fuel into space, which then freezes into a cloud of tiny crystals that reflect sunlight to Earth. The second stage is normally spinning when the fuel is released, which is what causes the spiral shape of the resulting cloud — and explains why the vortex continually expands before dissipating.

These spirals were once rare but are becoming more common as the number of Falcon 9 rocket launches increases.

One of the most recent examples was a never-before-seen "horned" spiral reported in May 2024 above parts of Europe. In April 2023, a stunning blue SpaceX spiral photobombed an aurora display above Alaska. The phenomenon has also been spotted twice by a camera attached to the Subaru Telescope on Hawaii's Mauna Kea; first in April 2022 and again in January 2023.

Not every Falcon 9 reentry results in a visible SpaceX spiral. But amateur astronomers can sometimes predict when they are likely to occur based on the rocket's trajectory, payload, spin rate and the time of the launch.

However, in this case, the launch information was not shared in advance because of the secrecy of the mission.