FOR DECADES scientists have argued over the age of the universe.

Now an expert from Sussex believes he and his colleagues have found the answer.

Dr John Gribbin says their research shows the universe is more than 13 billion years old.

And the findings by Dr Gribbin and colleagues Dr Simon Goodwin and Dr Martin Hendry at Sussex University may end an argument which has raged for more than 70 years.

In the Forties, experts believed the universe was two million years old. More recently its age was put at 16 billion years.

Dr Gribbin and his team spent six months studying complex information provided by NASA from the Hubble space telescope in their quest.

They found that spiral-shaped galaxies, such as the one the earth is in, are all roughly the same size, so from their brightness it is possible to work out how far away they are and how fast they are travelling.

Dr Gribbin, 52, who lives near Newhaven, said: "It is quite easy to work out that the universe is gradually moving apart but it is harder to measure the distances between the galaxies.

"The way we reached our conclusion is like measuring a car travelling down a road at 50mph. Once you know its speed and how far it has travelled, it can be timed back to a single point.

"Once we knew how fast the galaxies were travelling we could then work out how long ago they all began expanding from a single point - 13 billion years."

Dr Gribbin also believes his work shows that the Big Bang, the theory that that the universe was created in one super-explosion, is probably correct.

He said: "The big question now is whether the universe will keep on expanding forever or fall back into itself. The latest evidence suggests it will keep on expanding forever."

The story of the discovery is told in Dr Gribbin's new book, The Birth Of Time. His next project is to write a science book for children with his wife Mary.

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