universal time coordinate
11Time in physics — In physics, the treatment of time is a central issue. It has been treated as a question of geometry. One can measure time and treat it as a geometrical dimension, such as length, and perform mathematical operations on it. It is a scalar quantity… …
12Universal joint — A universal joint, U joint, Cardan joint, Hardy Spicer joint, or Hooke s joint is a joint in a rigid rod that allows the rod to bend in any direction, and is commonly used in shafts that transmit rotary motion. It consists of a pair of ordinary… …
13Solar time — On a prograde planet like the Earth, the sidereal day is shorter than the solar day. At time 1, the Sun and a certain distant …
14Civil time — In modern usage, civil time refers to statutory time scales designated by civilian authorities, or to local time indicated by clocks. Modern civil time is generally standard time in a time zone at a fixed offset from Coordinated Universal Time… …
15International Atomic Time — ( [http://www.bipm.org/en/scientific/tai/tai.html TAI] , from the French name Temps Atomique International) is a high precision atomic time standard that tracks proper time on Earth s geoid. It is the principal realisation of Terrestrial Time,… …
16Dynamical time scale — has two distinct meanings and usages, both related to astronomy: In one use, which occurs in stellar physics, the dynamical time scale is alternatively known as the freefall time scale, and is in general, the length of time over which changes in… …
17Geologic time scale — This clock representation shows some of the major units of geological time and definitive events of Earth history. The Hadean eon represents the time before fossil record of life on Earth; its upper boundary is now regarded as 4.0 Ga.[1] Other… …
18Daylight saving time — This article is about daylight saving time in general. For DST in a specific location, see Daylight saving time by country. Summer time and DST redirect here. For other uses, see Summer time (disambiguation) and DST (disambiguation) …
19System time — Unix date command In computer science and computer programming, system time represents a computer system s notion of the passing of time. In this sense, time also includes the passing of days on the calendar. System time is measured by a system… …
20Terrestrial Time — (TT) is the modern astronomical standard for the passage of time on the surface of the Earth (for civil purposes, Coordinated Universal Time (UTC) is standard). Since time moves at different rates for observers in different locations (due to… …
