precise ephemeris

См. также в других словарях:

• ephemeris second — Astron. the unit of ephemeris time, defined as a precise fraction of the length of the tropical year 1900. [1965 70] * * * ephemeris second, Astronomy. the fundamental unit of ephemeris time, adopted in 1956 by the International Bureau of Weights …   Useful english dictionary

• ephemeris second — Astron. the unit of ephemeris time, defined as a precise fraction of the length of the tropical year 1900. [1965 70] * * * …   Universalium

• ephemeris time — /əˈfɛmərəs taɪm/ (say uh femuhruhs tuym) noun Astronomy a measure of time independent of variations in the earth s rotation rate. The ephemeris second is the fundamental unit and is defined as a precise fraction of the tropical year 1900 …  

• точные эфемериды (положения НС на орбите) — Сведения о местоположении НС на орбите, получаемые после проведения траекторных измерений, описывающие реальное движение НС. [РТМ 68 14 01] Тематики спутниковая технология геодезических работ Обобщающие термины средства спутниковых определений EN …   Справочник технического переводчика

• Global Positioning System — GPS redirects here. For other uses, see GPS (disambiguation). Geodesy Fundamentals …   Wikipedia

• Planetary mass — The four terrestrial planets in the Solar System, to scale. Note that Mars (to the far right) is about half the diameter of the Earth, but only one ninth of the mass …   Wikipedia

• Atomic clock — Nuclear clock redirects here. For the clock as a measure for risk of catastrophic destruction, see Doomsday Clock. For a clock updated by radio signals (commonly but inaccurately called an atomic clock ), see Radio clock. For the album by Zion I …   Wikipedia

• Coordinated Universal Time — UTC redirects here. For other uses, see UTC (disambiguation). Coordinated Universal Time (abbreviated UTC) is the primary time standard by which the world regulates clocks and time. It is one of several closely related successors to Greenwich… …   Wikipedia

• Tropical year — A tropical year (also known as a solar year), for general purposes, is the length of 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,… …   Wikipedia

• Time standard — A time standard is any officially recognized specification for measuring time: either the rate at which time passes; or points in time; or both. For example, the standard for civil time specifies both time intervals and time of day. A time scale… …   Wikipedia

• Time — This article is about the measurement. For the magazine, see Time (magazine). For other uses, see Time (disambiguation). The flow of sand in an hourglass can be used to keep track of elapsed time. It also concretely represents the present as… …   Wikipedia