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.

Russia’s space agency has decided to cut the size of its crew complement on the International Space Station beginning in March 2017 to reduce operating costs until a new Russian science lab is activated on the complex in early 2018, officials confirmed this week.

After a four-day delay due to a ground power supply anomaly and unfavorable weather, an Ariane 5 rocket lifted off at 4:23 p.m. EST (2123 GMT) Tuesday to send into orbit a hush-hush communications satellite for the Egyptian military and a spacecraft to expand the capacity of Inmarsat’s mobile Internet service.