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NIST in Your Clock |
NIST develops, maintains and improves one of the world's most accurate clocks, thereby providing a time standard crucial for the leading edges of military and civilian technology and of science. |
Whenever you set a clock, the National Institute of Standards and Technology (NIST) ought
to come to mind. It is NIST's atomic clock in Boulder, Colorado, that serves as the
ultimate standard for setting every wristwatch, every wall clock, every computer clock. It
is how the "time lady" can sound so authoritative every time you call. That
"woman" is in frequent contact with NIST's atomic clock. Beyond calibrating
clocks, the extreme accuracy of atomic clocks provides the benchmarks for coordinating
massive, high speed transmission of voice and data signals over communication lines and
for controlling spacecraft. That accuracy is behind the satellite-mediated Global
Positioning System by which anyone with a hand-sized device can determine his or her
position on Earth within a 15 yard (14 meter) radius or so. The technology critically
depends upon measurements of the time it takes for electromagnetic signals to travel from
GPS satellites to GPS decoders on airplanes, ships, land vehicles or even in a hiker's
backpack. The accuracy of atomic clocks also helps unfetter the perpetual quest of
scientists to make ever more accurate and revealing measurements of nature--whether it be
the speed of light through the vast stretches of space or the movement of electrons
through microelectronic devices. The latest generation of atomic clocks can keep time with an accuracy equivalent to neither losing or gaining more than 1 second in 20 million years. Its version of a "pendulum" is a natural oscillation frequency of a cesium atom. The second is defined as exactly 9,192,631,770 of these atomic oscillations. NIST researchers continually work to improve the accuracy of its atomic clocks since each improvement in the past has led to deeper scientific insight and more capable technology. |
| Links: | NIST time. Take A Walk Through Time for a brief history of timekeeping and NIST's place in that history. Introduce yourself to NIST's Time and Frequency Division whose staff makes sure that a second is a second. Get answers to frequently asked questions about time and frequency. More Accurate Time:
NIST's New Year Gift to the World |