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This is part 5 in a series. Read part 1 , part 2 , part 3 and part 4 . The Leap Second Solution When atomic clocks were developed in the 1950s, scientists
This is part 4 in a series. Read part 1 , part 2 and part 3 . Greenwich Mean Time In the previous essay I introduced mean solar time, which averaged the annual
This is part 3 in a series. Read part 1 and part 2 . Oscillators and Clocks In the previous essay, I introduced the ideas that frequency and time interval are
This is part 2 in a series. Read part 1. A short history of frequency Frequency was originally considered to be the province of musicians. The pitches or
As a physicist in the National Institute of Standards and Technology (NIST) Time and Frequency Division, I have worked in the general area of operating atomic