SpaceX's reusable Falcon 9 will launch satellites into space after high winds delayed blast off by 24 hours.
The launch is due to take place at 2.17pm GMT (6.17am Pacific Time) on Thursday at California's Vandenberg Air Force base.
Bad weather forced experts to reschedule the much-anticipated lift-off on Wednesday.
Space enthusiasts can watch the rocket blast the satellites into low earth orbit on the livestream below.
The firm's primary mission for the launch is to deliver a Spanish satellite known as PAZ into orbit, which will provide imagery for commercial and government uses.
Falcon 9 is also carrying two of SpaceX's own prototype satellites, called Microsat-2a and -2b.
These form part of the company's first phase of testing into how to provide low-cost internet to people around the world by satellite.
SpaceX Falcon launch - In pictures
The Spanish satellite was built by Airbus and is operated by Hisdesat, part of Spain's national satellite company.
Elon Musk's company will also try to recover the fairings that fall off when the payload is lifted off into space, dashing to a "recovery zone" in the Pacific Ocean in a boat called Mr Steven.
SpaceX hit headlines earlier this month when space enthusiasts around the world watched its Falcon Heavy rocket - the most powerful in the world today - blast off from the Kennedy Space Centre in Florida.
Elon Musk's company will also try to recover the fairings that fall off when the payload is lifted off into space, dashing to a "recovery zone" in the Pacific Ocean in a boat called Mr Steven.
SpaceX hit headlines earlier this month when space enthusiasts around the world watched its Falcon Heavy rocket - the most powerful in the world today - blast off from the Kennedy Space Centre in Florida.
