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 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.

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.

LOS ANGELES — A sonic boom shook part of Southern California Saturday night as SpaceX’s Dragon spacecraft reentered Earth’s atmosphere. According to the Hawthorne-based company, the unpiloted spacecraft was expected to “announce its arrival” with a brief sonic boom before landing in the Pacific Ocean.

Physicists who record rocket launches and landings are learning important facts about the acoustics of spaceflight.

A SpaceX vehicle that has spent about a month docked at the International Space Station on a resupply mission is due to depart Thursday, May 22.

Unfavorable weather conditions have delayed the SpaceX Dragon's return to Earth from the International Space Station until at least Friday.