Live coverage: SpaceX Falcon Heavy launches NASA’s Psyche on mission to a metal asteroid

Ten days after the last liftoff from historic launch pad 39A in Florida, another SpaceX Falcon 9 rocket ignited its Merlin main engines for several seconds in a hold-down firing Thursday ahead of a planned expendable flight next week with an Inmarsat communications satellite.

The operation comes a week after NASA conducted a so-called ‘confidence test’ on Feb. 12, which was the process of loading some liquid hydrogen on the rocket’s core stage.

NASA has selected SpaceX to deliver supplies to the planned Gateway mini-space station in lunar orbit using a new version of the Dragon cargo vehicle launched atop Falcon Heavy rockets.