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Blog posts from Colorado

pair of feet standing on either side of the prime meridian in Greenwich, England

Everyday Time and Atomic Time: Part 4

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
wood pendulum clock hung on a wood paneled wall

Everyday Time and Atomic Time: Part 3

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
pipe organ

Everyday Time and Atomic Time: Part 2

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
NIST physicist Judah Levine with the NIST time scale, a digital clock face reading 14:33:34 and a bank of atomic clocks.

Everyday Time and Atomic Time: Part 1

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