Search results
Results from the WOW.Com Content Network
Universal Time (UT or UT1) is a time standard based on Earth's rotation. While originally it was mean solar time at 0° longitude, precise measurements of the Sun are difficult. Therefore, UT1 is computed from a measure of the Earth's angle with respect to the International Celestial Reference Frame (ICRF), called the Earth Rotation Angle (ERA ...
Coordinated Universal Time ( UTC) is the primary time standard globally used to regulate clocks and time. It establishes a reference for the current time, forming the basis for civil time and time zones. UTC facilitates international communication, navigation, scientific research, and commerce. UTC has been widely embraced by most countries and ...
This is a list of the UTC time offsets, showing the difference in hours and minutes from Coordinated Universal Time (UTC), from the westernmost (−12:00) to the easternmost (+14:00). It includes countries and regions that observe them during standard time or year-round. The main purpose of this page is to list the current standard time offsets ...
The Eastern Time Zone (ET) is a time zone encompassing part or all of 23 states in the eastern part of the United States, parts of eastern Canada, and the state of Quintana Roo in Mexico. Places that use: Eastern Standard Time (EST), when observing standard time (autumn/winter), are five hours behind Coordinated Universal Time (UTC−05:00).
Each time zone is defined by a standard offset from Coordinated Universal Time (UTC). The offsets range from UTC−12:00 to UTC+14:00, and are usually a whole number of hours, but a few zones are offset by an additional 30 or 45 minutes, such as in India and Nepal.
Conversion of units is the conversion of the unit of measurement in which a quantity is expressed, typically through a multiplicative conversion factor that changes the unit without changing the quantity. This is also often loosely taken to include replacement of a quantity with a corresponding quantity that describes the same physical property ...
SI base units. The SI comprises a coherent system of units of measurement starting with seven base units, which are the second (symbol s, the unit of time ), metre (m, length ), kilogram (kg, mass ), ampere (A, electric current ), kelvin (K, thermodynamic temperature ), mole (mol, amount of substance ), and candela (cd, luminous intensity ).
The United States Naval Observatory states "the Equation of Time is the difference apparent solar time minus mean solar time", i.e. if the sun is ahead of the clock the sign is positive, and if the clock is ahead of the sun the sign is negative. The equation of time is shown in the upper graph above for a period of slightly more than a year.