The flaming debris was part of the upper stage of a SpaceX Falcon 9 rocket that launched 22 of the company's Starlink internet satellites to orbit from California on Feb. 1, experts say. The Falcon 9 upper stage is expendable (unlike the rocket's first-stage booster) but is designed to be brought down in a controlled fashion shortly after launch.

The pyrotechnics were in fact caused by a Space X Falcon 9 rocket re-entering the Earth's atmosphere. There are reports of sightings in Denmark, Sweden and England. Pieces of the rocket then crashed into Poland and, experts say, may also have landed in Ukraine.