Atomic Clock Site

An atomic clock is the world’s most accurate timekeeping device. While a grandfather clock relies on a swinging pendulum and a digital watch relies on a vibrating quartz crystal, an atomic clock uses the ultra-stable vibrations of atoms—usually cesium or strontium—to measure the passage of time. How It Works

You likely interact with atomic clocks every day without realizing it: Atomic Clock

The best modern atomic clocks are so stable that they wouldn't lose or gain a single second in —a span of time longer than the age of the universe. An atomic clock is the world’s most accurate

Cesium atoms are sprayed into a vacuum chamber and hit with microwaves. Cesium atoms are sprayed into a vacuum chamber

High-speed data transfers and cellular networks require perfectly synchronized "stamps" to ensure packets of data arrive in the correct order.

Stock exchanges use atomic time to log trades down to the microsecond, preventing fraud and ensuring a fair "first-come, first-served" system.

Since 1967, the International System of Units (SI) has defined one second as exactly 9,192,631,770 oscillations of the radiation produced by this transition in a cesium-133 atom. Why It Matters