28 relations: Australia, Coordinated Universal Time, DORIS (geodesy), DUT1, Earth orientation parameters, Earth's rotation, Europe, Frame of reference, Galileo (satellite navigation), Geodesy, Global Positioning System, IERS Reference Meridian, International Astronomical Union, International Atomic Time, International Celestial Reference Frame, International Celestial Reference System, International Terrestrial Reference System, International Time Bureau, International Union of Geodesy and Geophysics, ΔT, Leap second, Paris Observatory, Satellite navigation, Time, United States, United States Naval Observatory, Universal Time, World Geodetic System.
Australia, officially the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania and numerous smaller islands.
Doppler Orbitography and Radiopositioning Integrated by Satellite or, in French, Détermination d'Orbite et Radiopositionnement Intégré par Satellite (in both case yielding the acronym DORIS) is a French satellite system used for the determination of satellite orbits (e.g. TOPEX/Poseidon) and for positioning.
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.
In geodesy, earth orientation parameters (EOP) are a collection of parameters that describe irregularities in the rotation of the Earth.
Earth's rotation is the rotation of Planet Earth around its own axis.
Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere.
In physics, a frame of reference (or reference frame) consists of an abstract coordinate system and the set of physical reference points that uniquely fix (locate and orient) the coordinate system and standardize measurements.
Galileo is the global navigation satellite system (GNSS) that is being created by the European Union (EU) through the European Space Agency (ESA), headquartered in Prague in the Czech Republic, with two ground operations centres, Oberpfaffenhofen near Munich in Germany and Fucino in Italy.
Geodesy, also known as geodetics, is the earth science of accurately measuring and understanding three of Earth's fundamental properties: its geometric shape, orientation in space, and gravitational field.
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.
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).
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.
In astrometry, an International Celestial Reference Frame (ICRF) is a realization of the International Celestial Reference System (ICRS) using reference celestial sources observed at radio wavelengths.
The International Celestial Reference System (ICRS) is the current standard celestial reference system adopted by the International Astronomical Union (IAU).
The International Terrestrial Reference System (ITRS) describes procedures for creating reference frames suitable for use with measurements on or near the Earth's surface.
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 International Union of Geodesy and Geophysics (IUGG; Union géodésique et géophysique internationale, UGGI) is an international non-governmental organisation dedicated to the scientific study of the Earth and its space environment using geophysical and geodetic techniques.
In precise timekeeping, ΔT (Delta T, delta-T, deltaT, or DT) is the time difference obtained by subtracting Universal Time (UT) from Terrestrial Time (TT):.
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 Paris Observatory (Observatoire de Paris or Observatoire de Paris-Meudon), a research institution of PSL Research University, is the foremost astronomical observatory of France, and one of the largest astronomical centres in the world.
A satellite navigation or satnav system is a system that uses satellites to provide autonomous geo-spatial positioning.
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.
The United States of America (USA), commonly known as the United States (U.S.) or America, is a federal republic composed of 50 states, a federal district, five major self-governing territories, and various possessions.
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.
The World Geodetic System (WGS) is a standard for use in cartography, geodesy, and satellite navigation including GPS.