The launch was scrubbed around 20 minutes before liftoff. The next launch opportunity will be Saturday, May 30 at 3:22 p.m. ET, NASA announced Wednesday afternoon.
Earlier Wednesday afternoon, the US National Weather Service (NWS) announced a tornado warning in Brevard County, Florida, although conditions cleared shortly afterward. Thunderstorms can cause residual electrical charges, which can potentially interact with rockets.
The two astronauts who were supposed to board the Dragon crew capsule, SpaceX’s reusable cargo spacecraft, are Doug Hurley and Bob Behnken. They were both selected to be astronauts by NASA in 2011. They have each flown twice on previous space shuttle missions, although this is the first time they will be completing a mission together, the New York Times reported.
The purpose of the mission is to test the Crew Dragon and is a final major step required for the Crew Dragon astronaut carrier to become certified by NASA's Commercial Crew Programme. Once the astronauts arrive, they are expected to remain at the station for one to four months.
The liftoff would have marked the first time that astronauts have launched from US soil since July 2011. Additionally, the launch would have marked the first time that private aerospace company SpaceX was in control of a space mission.
US President Donald Trump was expected to deliver remarks Wednesday following the event inside NASA’s Vehicle Assembly building. Since the launch has been scrubbed, the president has canceled the rest of his visit in Florida and will be returning to Washington, DC. However, Trump will return to Florida for the rescheduled launch on Saturday.