Photos: Atlas 5 rocket aims for International Space Station

The media briefing came after the agency formally pushed back the launch of the SpaceX Crew-9 mission to the International Space Station from mid-August to late-September.

SpaceX scrubbed the first test launch of its huge new rocket Monday due to a frozen valve in the pressurization system on the 33-engine Super Heavy booster, delaying the widely-anticipated flight from South Texas until at least Thursday.

Russian commander Anton Shkaplerov, NASA flight engineer Scott Tingle and Japanese astronaut Norishige Kanai docked with the International Space Station Tuesday at 3:39 a.m. EST (0839 GMT), two days after blastoff from the Baikonur Cosmodrome in Kazakhstan.