Cambridge University astronomers arrived at the figure by comparing data derived from five different techniques used by US and Israeli scientists, the International Astronomical Union (IAU) said Tuesday.

Four of these methods concur on an age of 14 billion years with an error margin of plus or minus two billion years, it said.

Three of the five models, when combined together, give the age as 13 billion years, again with an error margin of two billion years, it said.

The work will be presented in Manchester, England on Friday at the general assembly of the IAU, the most important global meeting of astronomers, the organisation's spokeswoman, Jacqueline Mitton, told AFP.

Putting an age to the universe "has been controversial, a big cosmological problem for decades," she said, noting that at various moments scientists had kicked around estimates ranging from 10 to 20 billion years.

"Fifteen billion years is the figure that has been around some time, but all the efforts to pin it down more precisely have proved difficult," she said.

The consensus of 14 billion years is an encouraging boost to that figure, as it is derived independently from a broad variety of calculation methods, she said, adding that the discrepancy of a billion years was "not all that significant" given the margin of error.

The debate is important, because the universe's age can be a vital factor in calculating the longevity of stars, the structure and movement of galaxies and whether the cosmos will expand infinitely.

Some methods have thrown up an age as young as 10 billion years, which has been strongly contested, as this does not concur with the estimated age of the oldest stars, which are believed to have been around for longer than that figure, Mitton said.

One measurement technique is to look at bright stars, such as exploding stars or super-bright stars in galaxies.

"If you know how bright they are intrinsically, and how bright they appear in the sky, you can deduce how far away the galaxy is," said Mitton.

The distance, in turn, gives a clue as to how fast the star is moving through the universe, opening the way to calculations of the date of the "Big Bang" -- the explosion that formed the universe, spewing out particles which later formed the stars, planets and the other phenomena of space.

The Cambridge team worked with scientists working in a broad range of cosmology, based in Durham, Britain; Chicago, Illinois, Arizona and Hawaii; and Jerusalem.

They caution, however, that more work remains to be done, mainly on understanding some conflicts of data between measurement techniques based on galaxy movement and galaxy clusters.

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