First Manned Spacex Flight.

SpaceX and NASA are closely monitoring the weather ahead of the historic launch of the Demo-2 mission, which is scheduled for 4:33 p.m. EDT Wednesday.

NASA astronauts Doug Hurley and Bob Behnken are scheduled to launch from Kennedy Space Center’s launch pad 39A, which was also used for the Apollo and space shuttle programs.

The launch will be the first time a private company, rather than a national government, sends astronauts into orbit. It will also be the first time that astronauts launch from U.S. soil since the final space shuttle mission in 2011.

 “Targeting 4:33 p.m. EDT today for Falcon 9’s launch of Crew Dragon with @NASA astronauts on board. Teams are closely monitoring launch and downrange weather,” tweeted SpaceX early on Wednesday.

 If SpaceX does not launch Wednesday, the next try would be on Saturday.