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Photos filched from hither and yon in the Northern Hemisphere of the spectacularly rich Draconids Meteor Shower on Saturday. Upper right: The meteor shower against a background of the Aurora Borealis in Greenland. It's called the Draconids because the shooting stars all seem to emanate from the constellation Draco.
Lower left: diagram of Earth's path through debris of comet 21P/Giacobini-Zinner. The shooting stars are pieces of debris burning up in Earth's atmosphere. Once a year on nearly the exact same date Earth passes through the debris fields of a handful of specific comets.