Nasa Co2 measuring satellite crashes following rocket malfunction.

How the OCO sattellite should have launched Nasa's first dedicated mission to measure carbon dioxide from space has failed following a rocket malfunction. Officials said the fairing - the part of the rocket which covers the satellite on top of the launcher - did not separate properly. Data indicates the spacecraft crashed into the ocean near Antarctica.

The Orbiting Carbon Observatory (OCO) was intended to help pinpoint the key locations on our planet's surface where CO2 is being emitted and absorbed.

Nasa officials confirmed the loss of the satellite at a press conference held at 1300 GMT.

John Brunschwyler, from Orbital Sciences Corporation, the rocket's manufacturer, told journalists: "Our whole team, at a very personal level, is very disappointed in the events of this morning." He added: "The fairing has considerable weight relative to the portion of the vehicle that's flying. So when it separates off, you get a jump in acceleration. We did not have that jump in acceleration. As a direct result of carrying that extra weight, we could not make orbit."

'Mishap' board

The $270m (£190m) mission was launched on a Taurus XL - the smallest ground-launched rocket currently in use by the US space agency.

Since its debut in 1994, this type of rocket has flown eight times, with six successes and two failures including this launch. But this is the first time Nasa has used the Taurus XL.

The US space agency will now put together a "Mishap Investigation Board" to determine the root cause of the problem.

Onlookers watched the launcher soar into the sky from the Vandenberg Air Force Base in California at 0955 GMT on Tuesday.

The first indication of a problem came in an announcement made by the Nasa launch commentator, George Diller.

"This is Taurus launch control. We have declared a launch contingency, meaning that we did not have a successful launch tonight," he said.

Separation of the fairing was one of the last technical hurdles faced by the satellite as it flew into orbit. Orbital said there had been no changes to the design of the fairing since previous launches.

Mr Brunschwyler, programme manager for the Taurus rockets, cast doubt on any suggestion of a link between the failure and a power glitch which occurred to the vehicle just prior to launch.

"That was on a separate system, so I do not believe there was any connection," Mr Brunschwyler told journalists at the Nasa press conference.

Dr Paul Palmer, a scientist from the University of Edinburgh, UK, who was collaborating on the mission, told BBC News: "I am bitterly disappointed about the loss of OCO. My thoughts go out to the science team that have dedicated the past seven years to building and testing the instrument."

Professor John Burrows, from the UK Centre for Ecology and Hydrology, who is also collaborating on the mission, commented: "The UK and European science community is a major partner in OCO and the loss of this instrument is a serious setback."

Scientists had hoped OCO would improve models of the Earth's climate and help researchers determine where the greenhouse gas is coming from and how much is being absorbed by forests and oceans.

This would have helped scientists make more accurate predictions of future climate change.

Rebuild question

Only about 50% of the carbon emitted from human sources - principally, from fossil fuel combustion - stays there. The remainder is mopped up by the land and oceans, which act as "sinks". However, scientists are unsure of the precise detail, with perhaps 20% of our CO2 going into a hitherto unrecognised sink.

"All eyes are now on the Japanese Gosat instrument to search for the missing carbon sink," said Dr Palmer.

Gosat was launched in January from Tanegashima in Japan. It is also designed to monitor atmospheric greenhouse gases.

Nasa's Glory satellite, which is designed to measure carbon soot and other aerosols in the Earth's atmosphere, is due to launch on a Taurus XL from California in June.

"Our goal will be to find a root cause for the problem. And we won't fly Glory until we have that data known to us," said Nasa's launch director Chuck Dovale.

Taurus is based on Orbital's air-launched Pegasus rockets which have a long, proud history. The fairing is essentially the same as is used on that rocket. Mr Brunschwyler said: "We have not had any issues with this fairing design in the past."

When the European Space Agency's Cryosat spacecraft was destroyed on launch in 2006, officials decided to re-build it; the launch is scheduled for later in the year. However, the future of the OCO mission remains unclear at this stage.

Responding to a question about spare parts for the US satellite, Michael Freilich, director of Nasa's Earth science division, said: "At this time, we don't have a complete inventory of flight spares, or what we should need, should we make a decision to re-build an OCO."

The only other failure to hit the Taurus rocket occurred in September 2001, when the rocket dropped off its payload of two satellites at a lower altitude than had been intended.