Atomic Clock

 

                                                                        Atomic Clock

An atomic clock is a type of clock that measures time based on the natural oscillations of atoms. These clocks are the most accurate timekeeping devices in existence

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Atomic Clock, 1949

Dr. Harold Lyons was a pioneering American physicist credited with developing the first operational atomic clock using ammonia molecules in 1949 at the National Bureau of Standards (NBS), now called NIST (National Institute of Standards and Technology), USA.

                            Lyons’ 1949 atomic clock marked the start of atomic timekeeping.

The First Atomic Clock (1949)

• Type: Ammonia-based atomic clock
• Mechanism: Used a microwave resonance technique involving ammonia (NH₃) molecules.
• Principle: Measured the frequency of radiation emitted when ammonia molecules transition between energy states.
• Frequency Standard: Around 23.87 GHz (for ammonia's inversion transition).

 

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