LOS ANGELES — A SpaceX Falcon 9 rocket blasted off from California on Saturday and placed a constellation of satellites in orbit, marking the company's first launch since a fireball engulfed a similar rocket on a Florida launch pad in September.

The two-stage rocket lifted off from Vandenberg Air Force Base at 9:54 a.m. carrying a payload for Iridium Communications, which is replacing its entire global network with 70 next-generation satellites.

The satellites were deployed about an hour after launch.

About nine minutes after the rocket blasted off, to cheers from the control room, its jettisoned first stage landed upright on a so-called droneship in the Pacific Ocean south of Vandenberg — part of Spacex's effort to make boosters reusable.

The company has succeeded six times previously with landings.