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“Bite-Size Bits of Local, National, and Global History”
“Bite-Size Bits of Local, National, and Global History”
Forest Hills in Washington, District of Columbia — The American Northeast (Mid-Atlantic)
 

First Atomic Clock, 1948

IEEE Milestone

 
 
First Atomic Clock, 1948 Marker image. Click for full size.
By Devry Becker Jones, December 17, 2017
1. First Atomic Clock, 1948 Marker
Inscription.

IEEE Milestone

First Atomic Clock, 1948

The first atomic clock, developed near this site by Harold Lyons at the National Bureau of Standards, revolutionized timekeeping by using transitions of the ammonia molecule as its source of frequency. Far more accurate than previous clocks, atomic clocks quickly replaced the Earth's rotational rate as the reference for world time. Atomic clock accuracy made possible many new technologies, including Global Positioning System (GPS).

August 2017

IEEE
 
Erected 2017 by Institute of Electrical and Electronics Engineers.
 
Location. 38° 56.524′ N, 77° 3.745′ W. Marker is in Forest Hills, District of Columbia, in Washington. Marker is at the intersection of Connecticut Avenue NW and Upton Street NW on Connecticut Avenue NW. Touch for map. Marker is at or near this postal address: 4000 Connecticut Ave NW, Washington DC 20008, United States of America.
 
Other nearby markers. At least 8 other markers are within walking distance of this marker. Connecticut Avenue Streetcars (about 500 feet away, measured in a direct line); 3. The Broadmoor (approx. 0.3 miles away); 15. Landscape (approx. 0.3 miles away);
First Atomic Clock, 1948 Marker image. Click for full size.
By Devry Becker Jones, December 17, 2017
2. First Atomic Clock, 1948 Marker
11. Bungalow (approx. 0.3 miles away); Soapstone Valley (approx. 0.4 miles away); 3524 Connecticut Avenue, N.W. (approx. 0.4 miles away); 12. Map (approx. half a mile away); Commerce (approx. half a mile away). Touch for a list and map of all markers in Forest Hills.
 
Categories. Science & Medicine
 
 
Credits. This page was last revised on December 18, 2017. This page originally submitted on December 17, 2017, by Devry Becker Jones of Silver Spring, Maryland. This page has been viewed 54 times since then and 3 times this year. Photos:   1, 2. submitted on December 17, 2017, by Devry Becker Jones of Silver Spring, Maryland. • Bill Pfingsten was the editor who published this page.
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