The launch for the second Falcon Heavy rocket from the Kennedy Space Center in Florida has slipped until Wednesday at the earliest. The powerful rocket is due to carry the Arabsat 6A communications satellite into orbit.

A Russian Progress supply ship launched Tuesday from the Baikonur Cosmodrome in Kazakhstan, firing into orbit from a snow-covered pad to haul three tons of fuel, water and equipment to the International Space Station.

The four members of the SpaceX Crew-11 flight were previously set to fly on different missions before they ended up as a quartet on the Dragon Endeavour spacecraft. Liftoff of the Falcon 9 rocket from pad 39A at NASA’s Kennedy Space Center is scheduled for no earlier than Friday, Aug. 1, at 11:43 a.m. EDT (1543 UTC).