Southern California residents were being warned to expect a large sonic boom Sunday evening as SpaceX launched a Falcon 9 rocket from Vandenberg Air Force Base before successfully executing its first-ever landing on the West Coast, according to the company and military officials.
The launch was scheduled for shortly after 7:20 p.m., Vandenberg Air Force base officials said in an advisory. The rocket carried the Argentinian SOACOM 1A radar mapping satellite.
Those near the base, which is near Lompoc, were able to see quite a show as the first stage of the Falcon 9 rocket burned its rocket engines to come to a gentle landing back at the air force base.
"During the landing attempt, residents from Santa Barbara, Ventura and San Luis Obispo counties may hear one or more sonic booms," according to the advisory issued prior to the launch. "A sonic boom is the sound associated with the shock waves from an aircraft or vehicle traveling faster than the speed of sound. Sonic booms generate a sound similar to an explosion or a clap of thunder."
It was SpaceX's first time trying to land one of its reusable rockets on the West Coast. Prior landings have taken place on the East Coast.
Before the launch, SpaceX CEO Elon Musk took to Twitter to warn Californians what was in store for them.
"Sonic boom warning. This won't be subtle," he wrote.
The loudness of the boom depends on the weather and other conditions, officials added.