Live: Watch NASA and SpaceX's historic mission to launch astronauts to the ISS
Follow live as NASA and SpaceX target 4:33 p.m. for the launch of astronauts Bob Behnken and Doug Hurley from Kennedy Space Center's pad 39A, the first time in nearly 10 years that astronauts will launch from American soil.
There will be no window for the mission known as Crew Dragon Demo-2. Because the capsule has to intercept the International Space Station some 250 miles overhead, teams must launch at 4:33 p.m. today or delay to no earlier than 3:22 p.m. Saturday.
Weather remains a concern for the launch.
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