A bright blue spiral seen over Europe was likely caused by SpaceX's Falcon 9 rocket launch.

A bright blue spiral seen in the skies over the UK and Europe on March 24 was likely caused by a SpaceX Falcon 9 rocket launch from Florida. The spiral formed as the rocket's frozen exhaust plume spun and reflected sunlight. Similar phenomena have been observed in previous SpaceX launches, dispelling any UFO theories.