NASA and SpaceX on Wednesday delayed the launch of a replacement crew of four astronauts to the International Space Station that would have set in motion the long-awaited homecoming of U.S. astronauts Butch Wilmore and Suni Williams.

NASA and SpaceX on Wednesday night scrubbed the Falcon 9 launch of a flight intended to retrieve from the International Space Station astronauts Suni Williams and Butch Wilmore, who have spent nine months in orbit.

With favorable weather forecast at Kennedy Space Center’s Launch Complex 39A, NASA’s SpaceX Crew-10 mission is set to launch at 7:49PM ET tonight. Flying into orbit atop a SpaceX Falcon 9 rocket, the Dragon spacecraft, will dock with the ISS at around 6:00AM ET on March 13th.