It's the first rocket launch since 2011.
At the Kennedy Space Center in Brevard County, Florida, Elon Musk's SpaceX and NASA are preparing for a historic moment that will happen today at 4:33 ET.
This launch is the first orbital launch in the U.S. since 2011 and a milestone in commercial areospace travel.
"We are once again launching American astronauts on American rockets from American soil," NASA Administrator Jim Bridenstine said during a news conference Tuesday. "This is a big moment in time. It's been nine years since we've had this opportunity."
The NASA astronauts, Robert Behnken and Douglas Hurley expect to spend one to three months in space.
Kids haven't seen this in their lifetime and many little space fans are looking forward to the launch, which can be streamed live through NASA's site.
If the Florida weather doesn't cooperate today the launch will happen on Saturday, May 30.
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