A SpaceX spacecraft has caused a sonic boom over California as it returned to Earth's atmosphere, and some on social media initially mistook the sound for an earthquake. One even thought a bomb had gone off.

Most of Southern California felt the shaking from a brief sonic boom created by SpaceX aircraft Dragon returning to Earth on Saturday night.

A SpaceX vehicle that has spent about a month docked at the International Space Station made a dramatic return Saturday night off the coast of California.