Nasa SpaceX launch - as it happened: Historic liftoff cancelled moments before takeoff over weather

SpaceX promo video for first crewed mission

Nasa has postponed its first launch of astronauts from US soil in nine years due to bad weather, just minutes before lift-off.

Robert Behnken and Douglas Hurley were due to travel to the International Space Station (ISS) on a rocket and capsule system built by billionaire entrepreneur Elon Musk's firm SpaceX.

But with rain and thunderstorms looming, the launch date has now been moved to Saturday at 20:22 pm UK time.

An estimated 1.7 million people from around the world tuned in to the launch from The Kennedy Space Centre in Florida.

However, as the weather conditions became worse, the US space agency "scrubbed" the mission for safety reasons less than 17 minutes before the Falcon 9 rocket was due to take off, along with the Crew Dragon spacecraft.

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[27 May 2020 13:59 · anthony.cuthbertson]

There's just over 7.5 hours to go until the launch, weather permitting. A lot could change in that time, but right now it's not looking good. Positive projections from earlier are now being revised. 

US Space Force 45th Weather Squadron says there is a high probability (90% chance) of rain and 60% chance of lightning during the launch period.

[27 May 2020 14:26 · anthony.cuthbertson]

Weather over the UK is looking a lot better, meaning that if the launch does go ahead then people in the UK will be able to spot the Falcon rocket passing overhead.

[27 May 2020 15:19 · Andrew Griffin]

Not everyone fancies a trip into space. Here's some YouGov polling that shows many people find the Moon frankly boring:

[27 May 2020 15:48 · Andrew Griffin]

There are still big fears that today's launch could be delayed by the weather. This photo from local space reporter Brendan Byrne certainly looks quite ominous.

[27 May 2020 16:20 · Andrew Griffin]

Here's the latest forecast from the US Air Force 45th Weather Squadron for today's launch today. It says there's a 50% chance that it'll go ahead, down from 60% yesterday.

As ever, this is very hard to predict, not least because a launch depends not only on the weather around Kennedy Space Center but all the way up the coast.

[27 May 2020 16:50 · Andrew Griffin]

Here from the Press Association is a rundown of Elon Musk's ambitions to get into space:

Elon Musk is on the cusp of a historic moment in his space ambitions, as SpaceX prepares to take two astronauts to the International Space Station (ISS) on Wednesday.

It is a crucial point for the entrepreneur, marking the first time a private company has attempted to send astronauts into space.

But his eye is very much set further than the ISS, and is locked on Mars...

Why is Elon Musk so interested in reaching Mars?

Musk said he started doing background research on space exploration in early 2002, after wondering why the US had made so little progress in putting humans in space since the Apollo missions - the last of which took place in 1972.

He spent some time inquiring about the cost of rockets and even went to Russia to find a cheaper alternative.

His first idea was called Mars Oasis, in which he conceptualised sending a small robotic lander to the Red Planet with seeds to start growing plants in martian radiated conditions.

SpaceX was founded in 2002, when Musk's wider space ambitions became serious, though Mars has remained one of his ultimate goals.

So is Elon Musk's plan for humans to one day visit Mars?

Musk's desire is not only for people to be able to visit Mars one day, but eventually to live there.

The 48-year-old wants to establish a self-sustaining city on the Red Planet, complete with iron foundries and even pizzerias.

And Musk fully intends to live there himself, previously saying he believes there is a "70% chance" he will make the trip.

How does he plan to get there?

Current efforts at SpaceX are focused on its Starship spacecraft, which Musk wants to use to not only reach the Moon and Mars, but also planets far beyond.

SpaceX says Starship will be the world's most powerful launch vehicle ever developed, able to carry more than 100 metric tonnes to Earth orbit.

Starship, coupled with a Super Heavy rocket, is intended to be a reusable transportation system capable of on orbit refuelling and utilising natural H2O and CO2 resources on Mars to refuel.

When does Musk want to reach Mars?

In 2017, Musk said he hoped to send unmanned spacecraft to Mars by 2022, followed by the first crewed flight in 2024.

[27 May 2020 17:30 · Andrew Griffin]

Weather permitting – both in Florida and over the Atlantic, which will decide whether the launch happens, as well as here – you might be able to see the rocket as it sails over the UK tonight. Here's how.

[27 May 2020 17:35 · Andrew Griffin]

Crews are now suiting up and getting on their way to the launchpad. The weather remains a concern, but otherwise we are go.

[27 May 2020 17:37 · Andrew Griffin]

When they arrive, they'll go through that access arm you can see on the right, and then into the crew capsule at the top.

[27 May 2020 17:41 · Andrew Griffin]

The chance of weather causing a "scrub" – the launch not going ahead – is now 60 per cent. The storm that is threatening the launch has moved onshore, which is good news, but there's still plenty of concern.