How Do Radio-Controlled Atomic Watches Work?
They’re Not Actually Atomic There are no radioactive parts in your atomic watch. The watch itself is just a regular digital watch. However, instead of keeping time via an internal mechanism or computer chip, a radio-controlled atomic watch stays in radio contact with an atomic clock. How Does an Atomic Clock Measure Time? Sundials measure time by the movement of a shadow. Water clocks measure seconds by drips of water. Mechanical clocks measure seconds by the turning of spring-driven gears. As human society grows more technological, it’s become more important than ever to find increasingly accurate means of keeping time. Atomic clocks measure time via the resonance frequency of an atom. As of 2009, atoms of cesium 133 are usually used, which are accurate to less than nine millionths of a second. In an atomic clock, a microwave oscillator bombards heated cesium atoms with radio waves. If an atom is hit by a radio wave of the exact right frequency, the electrons in that atom will change
