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 what would have been the first orbital mission from the US in nine years.
But unfavourable atmospheric conditions prompted controllers to call a stop just 16 minutes before lift-off.
The next opportunity for SpaceX and Nasa will come on 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 in 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.”
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