Q&A with Elon Musk, SpaceX’s founder and CEO

The U.S. Space Force’s Space Systems Command (SSC) and the Space Operations Command (SpOC) shifted the GPS 3 Space Vehicle 07 spacecraft to a SpaceX Falcon 9 rocket from a United Launch Alliance Vulcan rocket due to delays in Vulcan’s certification.

The mission will launch the first big block upgrade to the rocket since its first flight in 2023. Liftoff from SpaceX’s Starbase facilities in southern Texas is set for 4 p.m. CST (5 p.m. EST, 2200 UTC).

A Russian Soyuz rocket made a railroad journey Wednesday to its launch pad in Kazakhstan, two days before blastoff with a crew of three spaceflight veterans from the United States, Italy and Russia heading for the International Space Station.