A SpaceX Falcon 9 rocket carrying a communications satellite owned by Inmarsat had been fueled for liftoff, Monday from the Kennedy Space Center in Florida.
The satellite would provide broadband links for passengers and crews aboard ships and airplanes.
The launch for London-based Inmarsat on Monday will be the first of four SpaceX missions slated to blast off by the end of June from launch pads in Florida and California.
The successful launch of the missions would have a positive impact on SpaceX's backlogged manifest, which included 70 missions worth over $10 billion. These also included the company's lucrative contract to develop a human-rated spaceship to ferry astronauts to the International Space Station.
Since it arrived at the Florida launch base last month, the Boeing-built Inmarsat 5 F4 communications station has been fuelled with 5,372 pounds (2,437 kilograms) of hydrazine and nitrogen tetroxide propellants during a four-day procedure inside SpaceX's payload processing facility at Cape Canaveral.
The spacecraft was lifted on Falcon 9's payload adapter, made by Ruag Space in Sweden, ahead of encapsulation this week inside the rocket's composite payload fairing. (A payload fairing is a nose cone that serves to protect a spacecraft, from the impact of dynamic pressure and aerodynamic heating during launch through an atmosphere).
Meanwhile, SpaceX has achieved a major milestone in the development of the company's powerful new Falcon Heavy rocket, which was scheduled to fly for the first time a few months from now.
"First static-fire test of a Falcon Heavy center core completed at our McGregor, TX rocket-development facility last week," SpaceX representatives wrote on Twitter on 9 May, as an accompaniment to an 18-second video of the rocket test.