The newest "Cesium Fountain" Atomic Clock, which
established a new civilian time standard for the United
States last year.
(Image Source: National Institute of Standards and Technology,
U.S. Department of Commerce)
By Glenn A. Walsh
Reporting for SpaceWatchtower
International coordination of time is
now 140 years old.
One hundred, forty years ago today (May
20), a treaty among 17 nations (of 20 nations considering the
proposal), including the United States, was signed forming the International Bureau of Weights and
Measures. Officially known by its French name, Bureau International
des Poids et Mesures (BIPM), the Bureau was established to maintain
the International System of Units (SI) under the terms of the
Convention du Metre or Metric Convention. As of August of 2008, 51 nations have
signed the Metric Convention.
In America, time and measurement
standards are maintained by the National Institute of Standards of
Technology. From 1830 until 1901, weights and measures had been
maintained by the Office of Standard Weights and Measures in the U.S.
Department of the Treasury. In 1901, these responsibilities were
transferred to the U.S. Department of Commerce and enhanced with the
creation of the National Bureau of Standards.
With the passage of Public Law 100-418,
the National Bureau of Standards became the National Institute of
Standards and Technology on 1988 August 23. Many employees were quite
disappointed that the National Bureau of Standards name, which was
considered the gold-standard for the standards of weights, measures,
and time world-wide, would be discarded. However, the U.S. Congress
determined that the agency should take greater responsibility in
improving American industrial competitiveness throughout the world
and needed a new name to highlight the agency's new responsibilities.
One of the major responsibilities of
the International Bureau of Weights and Measures is to maintain
accurate, world-wide time-of-day. An official Coordinated Universal
Time (UTC) is established after the Bureau collects, analyzes, and
averages the atomic time measured and calculated by atomic clocks in
laboratories around the world, from nations who are signatories to
the Metric Convention.
This precise time standard and accurate
time synchronization are essential in our modern world. Global
navigation satellite systems rely on precise time for communication
systems of all kinds from satellites to cellular telephones,
electrical power grid synchronization, financial transactions, and
scientific applications. Of course, this includes GPS systems used by
millions of people world-wide.
Astronomy has always had a need for
precise time. Astronomers were the first to establish methods, using
the stars, to calculate exact time, using special telescopes called
transit telescopes.
In fact, beginning in 1869,
Pittsburgh's Allegheny Observatory, under Director Samuel Pierpont
Langley (who would go on to become the third Secretary of the
Smithsonian Institution, then considered the nation's greatest
scientific appointment), sold precise time to the railroads and
cities. This is considered the first regular and systematic system of
time distribution, using the telegraph. This precise time was derived
from the Allegheny Observatory's transit telescope and the proceeds
were used to fund Observatory operations and research.
This led to “Railroad Time” in
1883, which included the first five time zones in North America. The
railroads voluntarily established these time zones, to avoid
government action. The 1918 Standard Time Act brought these time
zones into Federal law.
More on the International Bureau of Weights and Measures ---
Link 1 >>> http://www.bipm.org/en/about-us/
Link 2 >>> http://en.wikipedia.org/wiki/International_Bureau_of_Weights_and_Measures
More on Standard Time ---
Link 1 >>> http://en.wikipedia.org/wiki/Standard_time
Link 2 (History in North America) >>> http://en.wikipedia.org/wiki/Standard_time#North_America
More on the National Institute of Standards and Technology, U.S. Department of Commerce ---
Link 1 >>> http://nist.gov/
Link 2 >>> http://en.wikipedia.org/wiki/National_Institute_of_Standards_and_Technology
More on Radio Stations Broadcasting International Time ---
Voice Announcements -
WWV (SW), Fort Collins CO: Link >>> http://en.wikipedia.org/wiki/WWV_%28radio_station%29
WWVH (SW), Kekaha HI: Link >>> http://en.wikipedia.org/wiki/WWVH
CHU (SW), Ottawa, ON Canada: Link >>> http://en.wikipedia.org/wiki/CHU_%28radio_station%29
Broadcast for Radio-Controlled Clocks -
WWVB (LW), Fort Collins CO: Link >>> http://en.wikipedia.org/wiki/WWVB
More on the Allegheny Observatory:
Link >>> http://spacewatchtower.blogspot.com/2012/08/centennial-new-allegheny-observatory.html
More on Samuel Pierpont Langley: Link >>> http://johnbrashear.tripod.com/bio/LangleySP.htm
Related Blog Posts ---
New Laser System Could Provide Mini Atomic Clocks (2014 Nov. 15):
Link >>> http://spacewatchtower.blogspot.com/2014/11/new-laser-system-could-provide-mini.html
New U.S. Atomic Clock World's Most Accurate (2014 April 26):
Link >>> http://spacewatchtower.blogspot.com/2014/04/new-us-atomic-clock-worlds-most-accurate.html
Even More Accurate Atomic Clock (2014 Jan. 27):
Link >>> http://spacewatchtower.blogspot.com/2014/01/even-more-accurate-atomic-clock.html
Laser Pulses Create More Accurate Atomic Clocks (2013 June 21):
Link >>> http://spacewatchtower.blogspot.com/2013/06/laser-pulses-create-more-accurate.html
Centennial: New Allegheny Observatory Dedication (2012 Aug. 28):
Link >>> http://spacewatchtower.blogspot.com/2012/08/centennial-new-allegheny-observatory.html
Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
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gaw
Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
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Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
< http://www.planetarium.
* Adler Planetarium, Chicago:
< http://adlerplanetarium.
* Astronomer, Educator, Optician John A. Brashear:
< http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
< http://www.andrewcarnegie.
* Civil War Museum of Andrew Carnegie Free Library:
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* Duquesne Incline cable-car railway, Pittsburgh:
< http://inclinedplane.tripod.
* Public Transit:
< http://andrewcarnegie2.tripod.
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