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Orion 'Mars ship' launch postponed Orion 'Mars ship' launch postponed
(35 minutes later)
The US space agency (Nasa) has aborted the launch of its Orion Mars capsule test mission, amid technical issues. The first test flight of the US space agency's Orion "Mars ship" has been postponed, amid technical issues.
The spacecraft had been due to launch on a short journey above the Earth to test key technologies - Nasa will try again in 24 hours. The capsule had been due to launch atop a Delta rocket on a short journey above the Earth to prove key technologies.
The maiden flight had been due to take place from Cape Canaveral in Florida between 12:05GMT and 14:44 GMT. Its maiden voyage was due to take place from Cape Canaveral in Florida between 12:05 GMT and 14:44 GMT.
But the countdown was held several times, due to a boat getting too close, winds and technical issues. But the countdown was interrupted by a boat getting too close, by gusty winds and by troublesome propellant valves.
Finally, space agency officials were forced to scrub Thursday's launch. Engineers will try again on Friday.
"Despite the valiant attempts of the launch team and mission managers around the country, we basically ran out of time in trying to troubleshoot," said Nasa spokesman Mike Curie."Despite the valiant attempts of the launch team and mission managers around the country, we basically ran out of time in trying to troubleshoot," said Nasa spokesman Mike Curie.
The conical vessel is reminiscent of the Apollo command ships that took men to the Moon in the 1960s and 1970s, but bigger and with cutting-edge systems.The conical vessel is reminiscent of the Apollo command ships that took men to the Moon in the 1960s and 1970s, but bigger and with cutting-edge systems.
Given that this is a first outing, there will be no people aboard. For this demonstration mission, it is being flown without people aboard.
The first delay on Thursday was because of a boat straying into the launch vicinity. Unacceptably strong gusts of wind subsequently forced the countdown to be halted. The first delay on Thursday was because of a boat straying into the launch vicinity. Unacceptably strong gusts of wind then forced a subsequent halt in the countdown.
Then there were technical issues with valves not operating properly on the rocket's big boosters. And finally, there were issues with valves not operating properly on the rocket's big boosters.
The decision to scrub Thursday's attempt was driven by the combination of problems. Lockheed Martin, the company developing Orion and running this test flight for Nasa, has another three days to get the mission off the ground before negotiations must take place for an extension.
Other space missions have bookings on the launch complex and they would have to agree to step aside. Unfortunately, the weather looks to be deteriorating over the next 24 hours.
'Big thing'
Orion is being developed alongside a powerful new rocket that will have its own debut in 2017 or 2018.Orion is being developed alongside a powerful new rocket that will have its own debut in 2017 or 2018.
Together, they will form the core capabilities needed to send humans beyond the International Space Station to destinations such as the Red Planet.Together, they will form the core capabilities needed to send humans beyond the International Space Station to destinations such as the Red Planet.
For the time being, the Delta IV-Heavy rocket - currently the beefiest launcher in the world - is being used as a stand-in.For the time being, the Delta IV-Heavy rocket - currently the beefiest launcher in the world - is being used as a stand-in.
If all goes well on Friday, it will send Orion twice around the globe, throwing the ship up to an altitude of almost 6,000km (3,600 miles). If all goes well on Friday, the Delta will send Orion twice around the globe, throwing the ship up to an altitude of almost 6,000km (3,600 miles).
This will set up a fast fall back to Earth, with a re-entry speed into the atmosphere close to 30,000km/h (20,000mph) - near what would be expected of a capsule coming back from the Moon.This will set up a fast fall back to Earth, with a re-entry speed into the atmosphere close to 30,000km/h (20,000mph) - near what would be expected of a capsule coming back from the Moon.
It should give engineers the opportunity to check the performance of Orion's critical heat shield, which is likely to experience temperatures in excess of 2,000C (4,000F).It should give engineers the opportunity to check the performance of Orion's critical heat shield, which is likely to experience temperatures in excess of 2,000C (4,000F).
They will also watch how the parachutes deploy as they gently lower the capsule into Pacific waters off Mexico's Baja California Peninsula.They will also watch how the parachutes deploy as they gently lower the capsule into Pacific waters off Mexico's Baja California Peninsula.
Jonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmosJonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmos