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Unmanned SpaceX rocket explodes after Florida launch Unmanned SpaceX rocket explodes after Florida launch
(35 minutes later)
An unmanned SpaceX Falcon-9 rocket has exploded minutes after lift-off from Cape Canaveral in Florida. An unmanned American Falcon-9 rocket has broken apart in flames minutes after lifting off from Cape Canaveral in Florida.
The US company SpaceX's rocket, which broke up over the Atlantic, was supposed to send a cargo ship to the International Space Station (ISS). Debris from the SpaceX vehicle tumbled out of the sky into the Atlantic Ocean.
As well as carrying supplies for the astronauts, the rocket had also been transporting a new docking port. The rocket, which had 18 straight successes prior to Sunday's flight, was in the process of sending a cargo ship to the International Space Station.
It is the Falcon-9 rocket's first failure in 19 launches. As well as carrying supplies for the astronauts, the Falcon had also been transporting a new docking port.
It was SpaceX's third failure at the manoeuvre - bids in January and April also failed. "The vehicle has broken up," said Nasa commentator George Diller, as TV images showed the white rocket falling to pieces.
"We appear to have had a launch vehicle failure," he added.
The problem occurred 139 seconds into the flight, just before the first-stage of the rocket was about to separate from the upper-stage, or top segment of the Falcon-9.
"There was an overpressure event in the upper-stage liquid oxygen tank," tweeted SpaceX CEO Elon Musk.
"Data suggests counterintuitive cause. That's all we can say with confidence right now. Will have more to say following a thorough fault tree analysis."
SpaceX will now lead an investigation, overseen by the Federal Aviation Authority and Nasa, which contracts the California company commercially to resupply the station.
Analysis: Jonathan Amos, BBC Science correspondentAnalysis: Jonathan Amos, BBC Science correspondent
Rockets are tremendously complex machines and every so often, they fail. SpaceX has built a reputation for being smart and fleet of foot, and most people would expect them to bounce back from this disappointment pretty quickly.Rockets are tremendously complex machines and every so often, they fail. SpaceX has built a reputation for being smart and fleet of foot, and most people would expect them to bounce back from this disappointment pretty quickly.
But the mission failure does have consequences for the future running of the International Space Station.But the mission failure does have consequences for the future running of the International Space Station.
It was already running its supplies at less than optimal levels. This was a consequence of launch failures on two other freighter systems - the US Cygnus ship and the Russian Progress craft. It was already running its supplies at less than optimal levels. This was a consequence of recent launch failures on two other freighter systems - the US Cygnus ship and the Russian Progress craft.
Before today the stores on the ISS were good until October. The Russians will now have another go at re-stocking the ISS next Friday and there will be an enormous amount riding on that flight as a result. Before today the stores on the ISS were good until October. The Russians will now have another go at re-stocking the ISS next Friday, and there will be an enormous amount riding on that flight as a result.
For the moment, the partner nations still plan to raise the current three-person crew to six in July. But they will surely keep that decision under review.For the moment, the partner nations still plan to raise the current three-person crew to six in July. But they will surely keep that decision under review.
"The vehicle has broken up," said Nasa commentator George Diller, after Nasa television broadcast images of the white rocket falling to pieces.
"We appear to have had a launch vehicle failure," Diller said.
"At this point it is not clear to the launch team exactly what happened."
The explosion happened a few moments into the flight.
A SpaceX commentator reportedly suggested the vehicle had been able to to reach supersonic speed, but something had happened before the cargo ship was able to detach from the first stage of the rocket and reach orbit.
Traditionally, launch vehicles are expendable. The different propellant stages of a rocket are dumped during the ascent to orbit and burn up on re-entry into the Earth's atmosphere.
But SpaceX believes that if it can carefully return, refurbish and re-fly these stages instead, it could substantially reduce the cost of access to space.
Whether that turns out to be the case - only time will tell, says the BBC's science correspondent Jonathan Amos.
But successful, the recovery procedure has the potential to revolutionise today's rocketry, our correspondent says.