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:
“There isn’t any universal reason;
And no one but a man would think there was.
You don’t catch women trying to be Plato.”
—Robert Frost (1874–1963)
“I have heard of a minister, who had been a fisherman, being settled in Bridgewater for as long a time as he could tell a cod from a haddock. Generous as it seems, this condition would empty most country pulpits forthwith, for it is long since the fishers of men were fishermen.”
—Henry David Thoreau (1817–1862)