NASA has postponed its first launch of astronauts from American soil since 2011.
Robert Behnken and Douglas Hurley were set to travel to the International Space Station (ISS) on board a Crew Dragon capsule, blasted into space by a Falcon 9 rocket built by billionaire entrepreneur Elon Musk’s firm SpaceX.
An estimated 1.7 million people from around the world tuned in to the launch from The Kennedy Space Centre in Florida.
But as the weather conditions became worse, the US space agency postponed the mission for safety reasons.
When is the next SpaceX and NASA launch due to take place?
Lift-off was planned to take place at 16:33 local time (21:22 BST) on Wednesday, from NASA’s Kennedy Space Center in Cape Canaveral, Florida.
The postponed launch will now take place on Saturday 30 May at 20:22 BST.
"We are not going to launch today."
— NASA (@NASA) May 27, 2020
Why was the first launch aborted?
The US Air Force’s 45th Weather Squadron, which monitors the weather for air and space operations, had forecast between a 40 per cent and 60 per cent chance of favourable conditions at the launch site in Florida.
NASA, which has strict rules about the conditions for crewed missions, said of one of which was being violated just minutes before the launch.
Speaking from the Crew Dragon capsule, Mr Hurley, who is the commander of the spacecraft, said: “We could see some raindrops on the windows and just figured that whatever it was, was too close to the launch pad at the time we needed it not to be.
“Understand that everybody’s probably a little bit bummed out. That’s just part of the deal.
He added: “We’ll do it again, I think, on Saturday.”
British astronaut Tim Peake said on Twitter: “What a shame – @SpaceX launch is scrubbed, but the rules are there in the interest of safety.
“A great rehearsal and reset for the next launch attempt in 3 days, Sat 30th at 15:22 (ET).”
How can I watch the launch on TV?
NASA was streaming the launch live on YouTube through its NASA TV channel and is likely to do the same again this Saturday.
Why is this mission so important?
The mission, known as Demo-2, will allow the US to once again send humans into space rather than relying on paying Russia for a lift on their spacecraft as they have done for the past nine years.
According to NASA, this is a demonstration mission to show SpaceX’s ability to ferry astronauts to the space station and back safely.
It is the final major step required by SpaceX’s astronaut carrier, the Crew Dragon, to get certified by NASA’s Commercial Crew Programme for more long-term crewed missions to space.