- SpaceX and Nasa was set to launch the Crew Dragon spacecraft at 9:33pm UK time
- The Falcon 9 rocket was due to lift off from the Kennedy Space Centre in Florida, bound for the International Space Station
- This would have been the first crewed launch from US soil since 2011
SpaceX and Nasa were forced to cancel a planned crewed mission to the International Space Station due to poor weather.
This launch was set to mark an important step in Nasa’s commercial crew programme, the agency’s partnership with private companies to send astronauts to space.
In the first crewed launch for the programme, astronauts Robert Behnken and Douglas Hurley were due to set off for the ISS in a spacecraft built by Elon Musk’s SpaceX.
The Falcon 9 rocket would have lifted off with the Crew Dragon capsule carrying the two men on a 19 hour journey to the space station.
Fuelling is going ahead
That’s a big moment – the launch director has given a “go” for propellant to be loaded into the rocket. This is the first time this has been done while humans are in the spacecraft.
The crew access arm has been retracted and the astronauts’ launch escape system has been activated. The weather “is trending in the right direction”, says Nasa’s livestream.
The big question now is how much rain we get between now and liftoff in 40 minutes.
Go for launch?
With less than an hour to go, everything looks technically fine, but we’re still having a few issues with the weather – Nasa’s mission control says status on rain and clouds has been “red” – meaning there are still concerns that they could disrupt the launch.
Mission Control says conditions are good at upper altitudes and there are hopes that the weather could clear in time. They’ll take another look at the weather in less than 5 minutes and then decide whether to fuel the rocket.
Today’s launch window is an “instantaneous” one – meaning the rocket has to lift off at exactly 4.33pm or we have to try again on Saturday.
Space Station gives the OK
The International Space Station also needs to give go-ahead for the launch, and says everything looks technically good for now.
After a 19 hour journey the two astronauts are due to arrive and dock at the station, where there are already three astronauts – American Chris Cassidy and Russians Anatoly Alekseevich and Ivan Vagner.
Hurley and Behnken are due to stay on the station for one to four months. The main purpose of their mission is to test the Crew Dragon.
The pad where today’s launch is taking place has a storied history. SpaceX has been leasing it from Nasa since 2014, but before that it was the site for many Space Shuttle launches.
The first launch in 1967 was uncrewed, but 39A’s biggest moment undoubtedly came in 1969, when it was the site for the Apollo 11 launch, which carried the first men to walk on the moon.
The President has landed
Air Force One, carrying President Donald Trump, just flew past the launchpad.
Mr Trump is set to become the first US president to watch a crewed launch since Bill Clinton watched the space shuttle Discovery launch in 1998. Until now Mr Clinton was the only president to ever watch a launch in person.
Space tech 2020
We are now under two hours from launch and the Nasa team is waiting on more information from weather beacons ahead of a final decision on whether to go ahead. The astronauts are in place and the hatch door is closed.
The Crew Dragon is somewhat more high-tech than the older Space Shuttles. Instead of knobs and buttons the console is full of touch screens, with the gloves on the astronauts’ space suits specially designed to work on the screens.
The spacecraft is autonomous but the astronauts have been trained to take over if something goes wrong.
A heavy responsibility
Today’s most touching moment was undoubtedly the astronauts’ last goodbye to their families. Both men were waved off on their long journey by their wives and sons.
Does Musk feel the responsibility for the safety of the two men his spacecraft now carries? “Yes, and I felt it most strongly when I saw their families.”
What did he say to them? “We’ve done everything we can to make sure that your dads come back.”
Elon’s big moment
One story here is the personal triumph of Elon Musk. His company, which he started in part with his own cash from fintech company PayPal, almost failed multiple times.
“This is a dream come true, both for me and the team at SpaceX,” he says today. “When I started SpaceX in 2002, I really didn’t think this would ever occur. I thought there was a 90pc chance we would fail to even get into low-earth orbit.”
In this configuration, he says, the rocket has flown “about 20 times”. “I don’t want to tempt fate, but we really have a well-proven rocket. This is the result of thousands of tests, thousands of design hours.”
The astronauts climb aboard
As Hurley and Behnken strap in and perform final checks we hear that the weather has been downgraded to 40pc favourable.
If it is cancelled today, backup dates are May 30 and 31st.
Some final comms checks are taking place to make sure the astronauts can clearly communicate with the ground operations centre. The spacecraft’s call sign is “SpaceX Dragon”.
This is no-one’s first rodeo – both astronauts flew into space on Nasa’s space shuttle programme, which ended in 2011. Doug Hurley flew on the very last launch, the Atlantis, which took place in July 2011.
Since then US astronauts have had to hitch a ride to the International Space Station on Russian shuttles. Today’s launch is the culmination of efforts to change that.
In 2014 SpaceX and Boeing were each given multi-billion dollar Nasa contracts to develop technology that could return US astronauts to orbit from American soil.
Watching the skies
Nasa currently has a 50/50 chance of the weather being good enough for the launch to go ahead.
Launches can be cancelled – sometimes at the last minute – because of wind or clouds.
Nasa released this fact sheet detailing the conditions which make launch impossible. They include winds of more than 30mph, nearby thunderstorms and wind shear “that could lead to control problems for the launch vehicle”.
The Teslas arrive
Bob and Doug are at the launchpad taking a “nature break” before they enter the capsule for the long wait before launch.
The Crew Dragon sits 230ft in the air on the top of the rocket, and the astronauts take a lift up to the top before walking along an access arm – a bit like an air bridge from a commercial aeroplane.
We are just over three hours ahead of launch and the astronauts have just set off on their way to the launchpad. The convoy of Model X Tesla cars carried the two men to the SpaceX rocket, which will carry them to the International Space Station.
Their walk to the cars was witnessed by SpaceX chief executive Elon Musk, Nasa administrator Jim Bridenstine and US Vice President Mike Pence, as well as the two astronauts’ families.