The article explains how atomic clocks, developed by organizations like NIST, measure time intervals using cesium atoms that absorb microwave radiation at a specific frequency. This frequency defines the international second, with cesium atomic clocks achieving accuracy within one three hundred millionths of a second per year. The article also discusses the evolution of time measurement from sundials to digital clocks, and how atomic clocks have enabled precise measurements and applications like GPS. Future optical atomic clocks promise even greater accuracy.
Source: https://www.nist.gov/how-do-you-measure-it/how-do-you-measure-second
Keywords: Resonance, Atomic clock, Frequency
