Last Friday, residents of Stockton, CA noticed an unusual cloud formation in the sky. Like most people, they rationally concluded it was caused by a UFO and took to Twitter to share the news with the world.

Not everyone is sure what caused the unusual cloud; CBS claims it was most likely caused by an airplane that disrupted the formation. But other, more accurate, news sources report that it is a hole punch cloud, which occurs when the water temperature of the cloud is below freezing but the water is not yet frozen. Once ice crystals form, the water droplets around the crystals evaporate, leaving a circular gap in the cloud.

In the face of a scientific explanation, some Stockton residents are sure we up against an alien invasion.