Live coverage: SpaceX’s next Falcon 9 rocket set for launch Sunday

These photos show the stacking of Japan’s eighth H-2B rocket inside an assembly building at the Tanegashima Space Center over the past few weeks, followed by rollout of the 186-foot-tall vehicle to its launch pad Tuesday.

SpaceX is gearing up for the first commercial launch of its powerful Falcon Heavy rocket as soon as early April with a communications satellite for Arabsat, and the U.S. Air Force hopes the two side boosters from the Arabsat mission can be safely landed and reused for the military’s first Falcon Heavy mission this summer, an exercise officials said will help certify previously-flown hardware for future national security launches.

A military communications satellite, built with international funding from Canada, Denmark, the Netherlands, Luxembourg and New Zealand, has been stacked atop a Delta 4 rocket to launch into a worldwide information-relay network operated by the U.S.