Butch Wilmore and Suni Williams need SpaceX to get a relief team to the space station before they can check out. Arrival is set for late Saturday night.

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.

SpaceX today scrubbed the expected 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,