It is the largest rocket ever launched from the U.S. West Coast.

The 235ft-tall Delta IV Heavy Launch Vehicle lifted off at 1.10pm local time yesterday with a classified U.S. government defence satellite on board.

Carrying cargo for the National Reconnaissance Office (NRO), the booster rose into the sky over California's central coast and arced over the Pacific Ocean, a spectacle visible from 50 miles away.
Delta IV -1
© Reuters
Blast off: The Delta IV Heavy Launch Vehicle lifts off from Vandenberg Air Force Base in the California desert at 1.10pm local time yesterday

record breaker rocket
© AP
Record breaker: The 235ft-tall spacecraft is the largest ever rocket to launch from the U.S. West Coast

The rocket hit speeds of 17,500mph as it climbed toward space.

Six minutes after lift-off, the first stage of the rocket broke away and splashed down in the Pacific.

United Launch Alliance (ULA), the joint venture of rocket builders Lockheed Martin and Boeing, said in a statement that the launch was a success.

It had been pushed back two minutes to avoid an object in space that could have been in the path of the rocket, said Michael J Rein, a ULA spokesman.

Yesterday marked the third of a series of six satellite launches taking place over an eight-month period. The next launch is scheduled to take place on February 5.

No cargo details were released, but the NRO operates satellites that provide information to the Central Intelligence Agency and U.S. Department of Defense.

There are currently three KH-11 satellites in orbit and some analysts believe that the purpose of this launch was to replace an imagery satellite that has been in orbit since 2001.
secret cargo
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Secret cargo: Carrying a classified U.S. government defence satellite, Delta IV rose into the sky over California's central coast and arced over the Pacific Ocean. The spectacle was visible over a wide area

secret cargo 2
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Its advanced resolution replacement is thought to be capable of seeing things on the ground in much finer detail than anything similar, although experts think it doubtful it will be able to read a car registration number.

'It will be used to produce high-resolution imagery of military and terrorist facilities around the world,' Jeffrey Richelson, an expert on U.S. space reconnaissance with the National Security Archive, told CNN.

This was the fifth launch of a Delta IV but the first from the West Coast. The other four launches were at Cape Canaveral, Florida.

Capable of generating nearly two million pounds of thrust, the liquid-fuel rocket has a central core booster and two strap-on boosters that make the assembly 50ft wide.
small delay
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Small delay: The launch had been pushed back two minutes to avoid an object in space that could have been in the path of the rocket

An upper second stage takes over when the first stage is exhausted.

Preparing for the launch took three years and $100million in infrastructure upgrades at Vandenberg, 130 miles north-west of Los Angeles.

The launch director, Lt. Col. Brady Hauboldt, said in a statement before the lift-off that the launch would mark a milestone by restoring heavy lift capability in the nation's western range. The last heavy lift Titan IV-B was launched at Vandenberg in 2005.

In its past, the launch complex was once configured for West Coast space shuttle launches, which were cancelled after the 1986 Challenger disaster, and the Air Force's Manned Orbiting Laboratory program, which was cancelled in 1969. It was last used in 2006.

NASA has set a target launch date of June 28 for the shuttle Atlantis and started preparations for the 135th and last shuttle flight.

The four-member crew will take up supplies to the International Space Station, make one spacewalk, and return a faulty pump.

Now three missions remain before NASA retires its shuttle fleet this year. The shuttle Discovery's last mission is slated for February 24, and Endeavour's is set for April.

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