As it happened: Bad weather halts historic Nasa SpaceX launch - BBC News
It would have been the first rocket launch with astronauts from US soil since 2011.
An early decision is made to delay to Saturday the first US astronaut launch in the US for nine years.

Poor weather has forced SpaceX to call off the launch of Nasa astronauts Doug Hurley and Bob Behnken to the International Space Station (ISS).

The two men were due to go up from the Kennedy Space Center in one of the company's new Dragon capsules at 16:33 local time (21:33 BST).

But unfavourable atmospheric conditions prompted controllers to call a stop to flight preparations for the day.

A tropical storm is also forming out over the Atlantic.

This would have been very close to the path of the astronauts' spaceship as it made its ascent to orbit.

SpaceX and Nasa will now have to wait until the space station is back in the right part of the sky to attempt another launch.

The earliest this can be is Saturday. If that's no good, there would be a third opportunity on Sunday.

There is great interest in this launch. Not since the retirement of the shuttles in 2011 has America been able to launch its own astronauts into space - a big gap in which the US has had to rely on Russian Soyuz vehicles.

But Hurley's and Behnken's mission is about more than just pride.

Nasa is giving up its past practice of owning and operating the space systems it uses low-Earth orbit and intends in future simply to buy crew transport services from the private sector – much like a company might outsource its payroll or HR needs.

SpaceX is the first of these new service providers.

Nasa Administrator Jim Bridenstine believes the approach will save his agency money that can then be spent on missions to the Moon and Mars.

“We envision a future where low-Earth orbit is entirely commercialised, where Nasa is one customer of many customers, where we have numerous providers that are competing on cost, on innovation and safety," he said.

"We are proving out a business model that ultimately enable us to go to the Moon this time sustainably. In other words we’re going to go to the Moon to stay.”