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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 variation in apparent solar time so as to
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 closely related concepts, and that the
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 frequencies of the notes in a musical scale
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 clocks and using output signals from them
Like everyone on the planet, our organization, the National Institute of Standards and Technology (NIST), became concerned with the COVID-19 outbreak in March 2020. NIST scientists were anxious to