Looking more like a small fridge than a high-tech device, the Aether Clock OC 020, by Japan`s Shimadzu Corp, isI the world`s most accurate clock. Standing about three feet tall with a 250-litre volume, it`s so precise it would drift by just one second in 10 billion years -100 times more accurate than current caesium atomic clocks.

While optical lattice clocks have existed, this is the first commercially available model. It reduces the need for frequent adjustments and is compact enough to be relocated easily. Potential applications include measuring gravitational shifts, monitoring plate tectonics and volcanic activity with centimetre-level accuracy.

Priced at $3.3 million, Shimadzu has already sold one unit and aims to sell ten more over three years, mainly to research institutions. The clock operates by trapping laser-cooled atoms in an opticallattice and analysing transitions in a cryogenically cooled chamber, using a system of lasers, an optical resonator and a vacuum chamber.•