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Taking Measure

Just a Standard Blog

Judah Levine

Judah Levine

Judah Levine has been a physicist at NIST and a professor at the University of Colorado Boulder since 1969. He is also a fellow of NIST and a fellow of JILA, a joint institute of the NIST and the University of Colorado Boulder. Presently, he designs the algorithms that realize UTC(NIST) and TA(NIST) and maintains the code that realizes these algorithms. He also designs and operates a number of services to distribute time and frequency information. These services include digital-network based services such as the Network Time Protocol and ACTS and services based on both geosynchronous and navigation satellites.

digital clock in orbit around Earth. The clock face reads 11:59:60.

Everyday Time and Atomic Time: Part 5

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 needed
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