A remarkable blue and white spiral observed across European skies late Monday was the result of frozen fuel released from a SpaceX rocket, according to meteorologists and scientists.
The UK’s Met Office reported on X that they received numerous accounts of an “illuminated swirl” in the sky Monday evening, likely caused by a rocket launched earlier from Cape Canaveral, Florida.
“Don’t be alarmed! It wasn’t a UFO, but rather the venting of a SpaceX Falcon 9 rocket,” stated Meteo France, the French national weather service, in the central Loire Valley region. Vivid images of the swirling pattern were also shared by social media users in countries including Sweden, Poland, Hungary, and Croatia.
People throughout Europe might have witnessed the spectacle, provided cloud cover didn’t obstruct their view, explained planetary scientist James O’Donoghue from the University of Reading in the UK. The spiral formed after the rocket’s first-stage booster detached, having propelled it from the ground, and the upper stage took over.
As the booster descended back to Earth, it expelled residual fuel, which crystallized into reflective particles. “These crystals captured sunlight, creating the luminous spiral design in the sky,” O’Donoghue clarified. “The spiral shape occurred because the tumbling rocket was rotating as it discharged the fuel.”
The swirl was a consequence of the SpaceX NROL-69 mission launch. The specific payload it carried into space remains classified. However, the mission was conducted on behalf of the National Reconnaissance Office, which oversees the US military’s reconnaissance satellites.
“The Falcon 9 reusable rocket booster successfully returned to Landing Zone 1 after delivering the national security payload to orbit,” the office confirmed in a statement. A similar spiral was documented above New Zealand in 2022, also attributed to the reliable Falcon 9 rocket, as reported at the time.
