Frozen fuel from the SpaceX Falcon 9 rocket created a luminous swirl that lasted for several minutes and could be seen from Britain and much of Europe.

The rocket launched from Florida’s Cape Canaveral Space Force Station during the afternoon hours, but it was already dark across Europe when it lifted off. As it zoomed across the sky to reach space, it produced a mesmerizing blue spiral that left many Europeans scratching their heads.

A large glowing spiral visible in the night sky on Monday is believed to have been caused by a SpaceX rocket launch in the US.