Universal Time (UT) is a time standard based on the rotation of the Earth. It is a modern continuation of Greenwich Mean Time (GMT), i.e., the mean solar time on the Prime Meridian at Greenwich, and GMT is sometimes used loosely as a synonym for UTC. In fact, the expression "Universal Time" is ambiguous, as there are several versions of it, the most commonly used being UTC and UT1 (see below). All of these versions of UT are based on the rotation of the Earth in relation to distant celestial objects (stars and quasars), but with a scaling factor and other adjustments to make them closer to solar time.
Read more about Universal Time: Universal Time and Standard Time, Measurement, Versions
Famous quotes containing the words universal and/or time:
“I had rather believe all the fables in the Legend, and the Talmud, and the Alcoran, than that this universal frame is without a Mind; and, therefore, God never wrought miracle to convince atheism, because his ordinary works convince it.”
—Francis Bacon (1561–1626)
“I left the woods for as good a reason as I went there. Perhaps it seemed to me that I had several more lives to live, and could not spare any more time for that one.”
—Henry David Thoreau (1817–1862)