New clock won't lose a second in 3.7bn years

SCIENTISTS have developed the world's most accurate clock – precise within milliseconds for the next 3.7 billion years.

The atomic clock, based on a single aluminium atom, is more than twice as accurate as the previous pacesetter based on a mercury atom.

Researchers say the new clock proves beyond doubt that aluminium is a better material to measure time than mercury.

The new "quantum logic clock", which will not gain or lose a second over the next 3.7 billion years, is based on a single electronically charged atom trapped by electric fields and vibrating at ultraviolet light frequencies.

These frequencies are 100,000 times higher than microwave frequencies used in other clocks around the world.

Scientists from America's National Institute of Standards and Technology say the new clock was a leap forward in time measurement.

Dr James Chou, who worked on the project, said: "This is a milestone for atomic clocks.

"In addition to demonstrating that aluminium is now a better time keeper than mercury, the latest results confirm that optical clocks are now widening their lead in some respects over the NIST-F1 caesium fountain clock.

"That clock is the US civilian standard time which currently keeps time to within one second in about 100 million years."