The US Air Force has a message for residents of Santa Barbara, Ventura, and San Luis Obispo counties—do not be alarmed on Sunday night around 7:30pm local time if you hear a loud noise. That’s just the sonic boom of a rocket’s first stage, returning from space, and landing for the first time ever at site along the West Coast of California.

On Sunday night, SpaceX is scheduled to launch a Falcon 9 rocket from Vandenberg Air Force Base in California, which is a couple of hours north of Los Angeles. While the company has landed several first stage boosters on a drone ship offshore from California, until now it has not attempted to land at a site along the coast. But now it has completed the “Landing Zone 4” facility and received the necessary federal approvals for rockets to make a vertical landing there.