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.

Parts of a Falcon 9 rocket have crashed to earth in an uncontrolled manner. An expert is concerned about the accumulation of incidents at SpaceX.

Debris from a SpaceX Falcon 9 rocket that blasted off in the United States on February 1 entered the Earth's atmosphere over Poland on Wednesday, the Polish space agency said. A 1.5 meter by one meter (five feet by three feet) chunk from an unidentified object was found near the western city of Poznan,