Cape Canaveral will host two back-to-back launches from rival companies Thursday.
Missions carried by both United Launch Alliance (ULA) and SpaceX are hoping to liftoff.
United Launch Alliance launched a military surveillance satellite aboard an Atlas V rocket at 6:29 a.m.
Less than thirteen hours later, at 7:03 p.m., a SpaceX Falcon 9 rocket will also fly from a nearby Cape Canaveral pad with South Korea's first lunar mission.
The Cape Canaveral spaceport is poised to surpass the record for most missions in a year to fly into orbit from its launch pads.
The launch day doubleheader would also mark the shortest span between two space launches from Florida’s Space Coast since 1967.