98 relations: Air traffic control, Amateur radio, Atomic clock, Aviation, Caesium, Caesium standard, Canada, Civil time, Classification of discontinuities, Coordinate time, Datasheet, Daylight saving time, Derivative, DUT1, Earth, Earth's rotation, England, English language, Ephemeris time, European Union, Flight plan, French language, Geoid, Global Positioning System, Greenwich Mean Time, Gregorian calendar, Ice age, Iceland, IERS Reference Meridian, Integer, International Astronomical Union, International Atomic Time, International Bureau of Weights and Measures, International Earth Rotation and Reference Systems Service, International Meridian Conference, International Space Station, International System of Units, International Telecommunication Union, International Time Bureau, Internet, Interval (mathematics), ISO 8601, ITU-R, Julian day, Kiribati, Large goods vehicle, Leap second, Line Islands, List of military time zones, List of UTC time offsets, ..., List of UTC timing centers, Louis Essen, Millisecond, National Institute of Standards and Technology, National Optical Astronomy Observatory, NATO phonetic alphabet, Network Time Protocol, Plate tectonics, Post-glacial rebound, Prime meridian, Proper time, Reykjavík, Rotation period, Rotational speed, Royal Navy, Royal Observatory, Greenwich, Scandinavia, Season, Second, Simon Newcomb, Solar time, Sundial, Tachograph, Telemetry, Terrestrial Time, Tidal acceleration, Time, Time dilation, Time signal, Time standard, Time zone, Timekeeping on Mars, Timestamp, Tropical year, United States Coast Guard, United States Naval Observatory, Universal Time, USA Today, UTC offset, UTC+14:00, UTC−10:00, UTC−12:00, UTC±00:00, Weather forecasting, World Radiocommunication Conference, World Wide Web, WWV (radio station), 24-hour clock. Expand index (48 more) » « Shrink index
Air traffic control (ATC) is a service provided by ground-based air traffic controllers who direct aircraft on the ground and through controlled airspace, and can provide advisory services to aircraft in non-controlled airspace.
Amateur radio, also known as ham radio, describes the use of radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communication.
An atomic clock is a clock device that uses an electron transition frequency in the microwave, optical, or ultraviolet region of the electromagnetic spectrum of atoms as a frequency standard for its timekeeping element.
Aviation, or air transport, refers to the activities surrounding mechanical flight and the aircraft industry.
Caesium (British spelling and IUPAC spelling) or cesium (American spelling) is a chemical element with symbol Cs and atomic number 55.
The caesium standard is a primary frequency standard in which electronic transitions between the two hyperfine ground states of caesium-133 atoms are used to control the output frequency.
Canada is a country located in the northern part of North America.
In modern usage, civil time refers to statutory time scales designated by civilian authorities, or to local time indicated by clocks.
Continuous functions are of utmost importance in mathematics, functions and applications.
In the theory of relativity, it is convenient to express results in terms of a spacetime coordinate system relative to an implied observer.
A floppy disk controller datasheet. A datasheet, data sheet, or spec sheet is a document that summarizes the performance and other technical characteristics of a product, machine, component (e.g., an electronic component), material, a subsystem (e.g., a power supply) or software in sufficient detail to be used by a design engineer to integrate the component into a system.
Daylight saving time (abbreviated DST), sometimes referred to as daylight savings time in U.S., Canadian, and Australian speech, and known as summer time in some countries, is the practice of advancing clocks during summer months so that evening daylight lasts longer, while sacrificing normal sunrise times.
The derivative of a function of a real variable measures the sensitivity to change of the function value (output value) with respect to a change in its argument (input value).
The time correction DUT1 (sometimes also written DUT) is the difference between Universal Time (UT1), which is defined by Earth's rotation, and Coordinated Universal Time (UTC), which is defined by a network of precision atomic clocks.
Earth is the third planet from the Sun and the only astronomical object known to harbor life.
Earth's rotation is the rotation of Planet Earth around its own axis.
England is a country that is part of the United Kingdom.
English is a West Germanic language that was first spoken in early medieval England and is now a global lingua franca.
The term ephemeris time (often abbreviated ET) can in principle refer to time in connection with any astronomical ephemeris.
The European Union (EU) is a political and economic union of EUnum member states that are located primarily in Europe.
Flight plans are documents filed by a pilot or flight dispatcher with the local Civil Aviation Authority (e.g. the FAA in the United States) prior to departure which indicate the plane's planned route or flight path.
French (le français or la langue française) is a Romance language of the Indo-European family.
The geoid is the shape that the surface of the oceans would take under the influence of Earth's gravity and rotation alone, in the absence of other influences such as winds and tides.
The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Air Force.
Greenwich Mean Time (GMT) is the mean solar time at the Royal Observatory in Greenwich, London.
The Gregorian calendar is the most widely used civil calendar in the world.
An ice age is a period of long-term reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers.
Iceland is a Nordic island country in the North Atlantic, with a population of and an area of, making it the most sparsely populated country in Europe.
The IERS Reference Meridian (IRM), also called the International Reference Meridian, is the prime meridian (0° longitude) maintained by the International Earth Rotation and Reference Systems Service (IERS).
An integer (from the Latin ''integer'' meaning "whole")Integer 's first literal meaning in Latin is "untouched", from in ("not") plus tangere ("to touch").
The International Astronomical Union (IAU; Union astronomique internationale, UAI) is an international association of professional astronomers, at the PhD level and beyond, active in professional research and education in astronomy.
International Atomic Time (TAI, from the French name temps atomique international) is a high-precision atomic coordinate time standard based on the notional passage of proper time on Earth's geoid.
The International Bureau of Weights and Measures (Bureau international des poids et mesures) is an intergovernmental organization established by the Metre Convention, through which Member States act together on matters related to measurement science and measurement standards.
The International Earth Rotation and Reference Systems Service (IERS), formerly the International Earth Rotation Service, is the body responsible for maintaining global time and reference frame standards, notably through its Earth Orientation Parameter (EOP) and International Celestial Reference System (ICRS) groups.
The International Meridian Conference was a conference held in October 1884 in Washington, D.C., in the United States, to determine a prime meridian for international use.
The International Space Station (ISS) is a space station, or a habitable artificial satellite, in low Earth orbit.
The International System of Units (SI, abbreviated from the French Système international (d'unités)) is the modern form of the metric system, and is the most widely used system of measurement.
The International Telecommunication Union (ITU; Union Internationale des Télécommunications (UIT)), originally the International Telegraph Union (Union Télégraphique Internationale), is a specialized agency of the United Nations (UN) that is responsible for issues that concern information and communication technologies.
The International Time Bureau (Bureau International de l'Heure, abbreviated BIH) seated at the Paris Observatory, was the international bureau responsible for combining different measurements of Universal Time.
The Internet is the global system of interconnected computer networks that use the Internet protocol suite (TCP/IP) to link devices worldwide.
In mathematics, a (real) interval is a set of real numbers with the property that any number that lies between two numbers in the set is also included in the set.
ISO 8601 Data elements and interchange formats – Information interchange – Representation of dates and times is an international standard covering the exchange of date- and time-related data.
The ITU Radiocommunication Sector (ITU-R) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU) and is responsible for radio communication.
Julian day is the continuous count of days since the beginning of the Julian Period and is used primarily by astronomers.
Kiribati, officially the Republic of Kiribati (Gilbertese: Ribaberiki Kiribati),.
A heavy goods vehicle (HGV), also large goods vehicle (LGV) or medium goods vehicle, is the European Union (EU) term for any truck with a gross combination mass (GCM) of over. Sub-category N2 is used for vehicles between and and N3 for all goods vehicles over as defined in Directive 2001/116/EC. The term medium goods vehicle is used within parts of the UK government to refer to goods vehicles of between 3.5 and 7.5 tonnes which according to the EU are also "large goods vehicles". Commercial carrier vehicles of up to are referred to as Light commercial vehicles and come into category N1. Confusingly though, parts of the UK government refer to these as "light goods vehicles" (also abbreviated "LGV"), with the term LGV" appearing on tax discs for these smaller vehicles. Tax discs use the term "HGV" for vehicles over 3.5 tonnes. HGVs must not exceed 40 tonnes laden weight or in length to cross boundaries in the EU, but longer and heavier vehicles (LHVs) known as Gigaliner, EuroCombi, EcoLiner, innovative commercial vehicle, mega-truck, etc., typically long and weighing up to 60 tonnes are used in some countries, and the implications of allowing them to cross borders was being considered.
A leap second is a one-second adjustment that is occasionally applied to Coordinated Universal Time (UTC) in order to keep its time of day close to the mean solar time as realized by UT1.
The Line Islands, Teraina Islands or Equatorial Islands, is a chain of atolls (with partially or fully enclosed lagoons) and coral islands (with a surrounding reef).
This is a list of military time zones as defined in the ACP 121(I) standard.
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).
List of UTC timing centers is a list of over 70 recognized maintainers of atomic clocks around the world from which UTC is calculated.
Louis Essen FRS O.B.E. (6 September 1908 – 24 August 1997) was an English physicist whose most notable achievements were in the precise measurement of time and the determination of the speed of light.
A millisecond (from milli- and second; symbol: ms) is a thousandth (0.001 or 10−3 or 1/1000) of a second.
The National Institute of Standards and Technology (NIST) is one of the oldest physical science laboratories in the United States.
The National Optical Astronomy Observatory (NOAO) is the United States national observatory for ground-based nighttime ultraviolet-optical-infrared (OUVIR) astronomy.
The NATO phonetic alphabet, officially denoted as the International Radiotelephony Spelling Alphabet, and also commonly known as the ICAO phonetic alphabet, and in a variation also known officially as the ITU phonetic alphabet and figure code, is the most widely used radiotelephone spelling alphabet.
Network Time Protocol (NTP) is a networking protocol for clock synchronization between computer systems over packet-switched, variable-latency data networks.
Plate tectonics (from the Late Latin tectonicus, from the τεκτονικός "pertaining to building") is a scientific theory describing the large-scale motion of seven large plates and the movements of a larger number of smaller plates of the Earth's lithosphere, since tectonic processes began on Earth between 3 and 3.5 billion years ago.
Post-glacial rebound (also called isostatic rebound or crustal rebound) is the rise of land masses after the lifting of the huge weight of ice sheets during the last glacial period, which had caused isostatic depression.
A prime meridian is a meridian (a line of longitude) in a geographic coordinate system at which longitude is defined to be 0°.
In relativity, proper time along a timelike world line is defined as the time as measured by a clock following that line.
Reykjavík is the capital and largest city of Iceland.
In astronomy, the rotation period of a celestial object is the time that it takes to complete one revolution around its axis of rotation relative to the background stars.
Rotational speed (or speed of revolution) of an object rotating around an axis is the number of turns of the object divided by time, specified as revolutions per minute (rpm), cycles per second (cps), radians per second (rad/s), etc..
The Royal Navy (RN) is the United Kingdom's naval warfare force.
The Royal Observatory, Greenwich (ROG; known as the Old Royal Observatory from 1957 to 1998, when the working Royal Greenwich Observatory, RGO, moved from Greenwich to Herstmonceux) is an observatory situated on a hill in Greenwich Park, overlooking the River Thames.
Scandinavia is a region in Northern Europe, with strong historical, cultural and linguistic ties.
A season is a division of the year marked by changes in weather, ecology, and amount of daylight.
The second is the SI base unit of time, commonly understood and historically defined as 1/86,400 of a day – this factor derived from the division of the day first into 24 hours, then to 60 minutes and finally to 60 seconds each.
Simon Newcomb (March 12, 1835 – July 11, 1909) was a Canadian–American astronomer, applied mathematician and autodidactic polymath, who was Professor of Mathematics in the U.S. Navy and at Johns Hopkins.
Solar time is a calculation of the passage of time based on the position of the Sun in the sky.
A sundial is a device that tells the time of day when there is sunlight by the apparent position of the Sun in the sky.
A tachograph is a device fitted to a vehicle that automatically records its speed and distance, together with the driver's activity selected from a choice of modes.
Telemetry is an automated communications process by which measurements and other data are collected at remote or inaccessible points and transmitted to receiving equipment for monitoring.
Terrestrial Time (TT) is a modern astronomical time standard defined by the International Astronomical Union, primarily for time-measurements of astronomical observations made from the surface of Earth.
Tidal acceleration is an effect of the tidal forces between an orbiting natural satellite (e.g. the Moon), and the primary planet that it orbits (e.g. Earth).
Time is the indefinite continued progress of existence and events that occur in apparently irreversible succession from the past through the present to the future.
According to the theory of relativity, time dilation is a difference in the elapsed time measured by two observers, either due to a velocity difference relative to each other, or by being differently situated relative to a gravitational field.
A time signal is a visible, audible, mechanical, or electronic signal used as a reference to determine the time of day.
A time standard is a specification for measuring time: either the rate at which time passes; or points in time; or both.
A time zone is a region of the globe that observes a uniform standard time for legal, commercial, and social purposes.
Various schemes have been used or proposed for timekeeping on the planet Mars independently of Earth time and calendars.
A timestamp is a sequence of characters or encoded information identifying when a certain event occurred, usually giving date and time of day, sometimes accurate to a small fraction of a second.
A tropical year (also known as a solar year) is the time that the Sun takes to return to the same position in the cycle of seasons, as seen from Earth; for example, the time from vernal equinox to vernal equinox, or from summer solstice to summer solstice.
The United States Coast Guard (USCG) is a branch of the United States Armed Forces and one of the country's seven uniformed services.
The United States Naval Observatory (USNO) is one of the oldest scientific agencies in the United States, with a primary mission to produce Positioning, Navigation and Timing (PNT) for the United States Navy and the United States Department of Defense.
Universal Time (UT) is a time standard based on Earth's rotation.
USA Today is an internationally distributed American daily, middle-market newspaper that serves as the flagship publication of its owner, the Gannett Company.
The UTC offset is the difference in hours and minutes from Coordinated Universal Time (UTC) for a particular place and date.
UTC+14:00 is an identifier for a +14 hour time offset from UTC.
UTC−10:00 is a time offset that subtracts 10 hours from Coordinated Universal Time (UTC).
UTC−12:00 is a time offset that subtracts 12 hours from Coordinated Universal Time (UTC).
UTC±00:00 is the following time.
Weather forecasting is the application of science and technology to predict the conditions of the atmosphere for a given location and time.
World Radiocommunication Conference (WRC) is organized by ITU to review and as necessary, revise the Radio Regulations, the international treaty governing the use of the radio-frequency spectrum and the geostationary-satellite and non-geostationary-satellite orbits.
The World Wide Web (abbreviated WWW or the Web) is an information space where documents and other web resources are identified by Uniform Resource Locators (URLs), interlinked by hypertext links, and accessible via the Internet.
WWV is the call sign of the United States National Institute of Standards and Technology's (NIST) HF ("shortwave") radio station located near Fort Collins, Colorado.
The 24-hour clock is the convention of time keeping in which the day runs from midnight to midnight and is divided into 24 hours, indicated by the hours passed since midnight, from 0 to 23.
Co-ordinated Universal Time, Co-ordinated universal time, Coordinated universal time, History of UTC, ITU-R TF.460-4, Temps Universel Coordonné, Time in Space, U.T.C, U.T.C., UTC, UTC (Internet), UTC Internet, UTC time, UTC(Internet), Universal Coordinated Time, Universal Time Co-ordinated, Universal Time Coordinate, Universal Time Coordinated, Universal Time Coordination, Universal Time, Coordinated, Universal co-ordinated time, Universal time coordinated, Utc, Zulu Time, Zulu time.