There is a two hour window for them to either launch or scrub. Archive: https://archive.today/MNSqn From the post: >>The first crewed lunar mission in more than 50 years is scheduled to launch on Wednesday, and NASA will be streaming a front row seat for everyone interested. The crew of four astronauts will be the first people to fly to the moon since Apollo 17’s Gene Cernan and Harrison Schmitt closed out the triumphant lunar-landing program in 1972. They won't be landing, though.