Time lapse: Watch the Falcon Heavy placed on pad 39A

A United Launch Alliance Atlas 5 rocket is set to roll to its launch pad Wednesday at Cape Canaveral, a day before liftoff with a new-generation NOAA weather satellite. The launch of a SpaceX Falcon 9 rocket with a Spanish communications satellite is expected to be shuffled after the Atlas 5 flight in a rapid-fire launch sequence at the Florida spaceport this week.

A Falcon 9 rocket booster — under the power of a single Merlin 1D engine — descends toward a specially-outfitted ocean landing platform off Florida’s East Coast on Tuesday in a brief video clip released by SpaceX.

The launch of a U.S.-French oceanography satellite from California has been postponed from July 22 after engineers discovered contamination in one of the spacecraft’s thrusters at its factory in France.