The term ephemeris time (often abbreviated ET) can in principle refer to time in association with any ephemeris (itinerary of the trajectory of an astronomical...

celestial navigation, an ephemeris (/ɪˈfɛmərəs/; pl. ephemerides /ˌɛfəˈmɛrədiːz/; from Latin ephemeris 'diary', and Greek ἐφημερίς (ephemeris) 'diary, journal')...

transition, newly established, with the ephemeris second. The ephemeris second is a unit in the system of time that, when used as the independent variable...

time standards such as sidereal time and ephemeris time, for most practical purposes, by newer time standards based wholly or partly on atomic time using...

century. Time standards based on Earth rotation were replaced (or initially supplemented) for astronomical use from 1952 onwards by an ephemeris time standard...

Supplement to the Astronomical Ephemeris and the American Ephemeris and Nautical Almanac, p. 9, ... defined ephemeris time ... [was] adopted by the International...

third release of the JPL Ephemeris Tapes, and was a special purpose, short-duration ephemeris. The then-current JPL Export Ephemeris was DE19. These early...

(non-relativistic) former standard of ephemeris time (adopted by the IAU in 1952 and superseded 1976). In 2006, after a history of multiple time-scale definitions and...

ephemeris second (see Ephemeris time - redefinition of the second). In 1976, however, the IAU resolved that the theoretical basis for ephemeris time was...

In this role, TT continues Terrestrial Dynamical Time (TDT or TD), which succeeded ephemeris time (ET). TT shares the original purpose for which ET was...

1879, Shaka Era, or 22 March 1957. India has adopted pie Ephemeris Time in the Indian Ephemeris from 1960 onwards in pursuance of the resolution passed...

second offset is to provide continuity with the older ephemeris time. "History of TAI−UTC". Time Service Dept., United States Naval Observatory. 2009....

of mean solar time (UT2) (result: 9192631830 cycles) and also the second of ephemeris time (ET) (result:9192631770 ± 20 cycles), see "Time Scales", by L...

of the astronomical time scale ephemeris time (ET). In 1967 the International System of Units (SI) standardized its unit of time, the second, on the properties...

Raphael's Ephemeris is an ephemeris, or set of tables, used in astrology to determine the position of the Sun, Moon and planets. Raphael was a pseudonym...

basis for ephemeris time (ET) was wholly non-relativistic, and therefore, beginning in 1984 ephemeris time would be replaced by two further time scales with...

Propulsion Laboratory as Development Ephemeris. The latest releases include DE430 which covers planetary and lunar ephemeris from Dec 21, 1549 to Jan 25, 2650...

1986, 281-292 Explanatory Supplement to the Astronomical Ephemeris and the American Ephemeris and Nautical Almanac, Nautical Almanac Offices of UK and...

rate, astronomers introduced Ephemeris Time, which has since been replaced by Terrestrial Time (TT). Because Universal Time is determined by the Earth's...

standard atomic clock was carried out by the use of the astronomical time scale ephemeris time (ET). As of 2013, the most stable atomic clocks are ytterbium...

Equation of Ephemeris Time: 1532  (prior to the distinction that is now made between EOT, E, and Δt the latter was known as the equation of time) is Δ t =...

the Gregorian calendar are used. For continuity with its predecessor Ephemeris Time, TCG was set to match ET at around Julian Date 2443144.5 (1977-01-01T00Z)...

known in Halley's time that what is actually occurring includes a slowing-down of Earth's rate of rotation: see also Ephemeris time – History. When measured...

sandglass, sand timer, or sand clock) is a device used to measure the passage of time. It comprises two glass bulbs connected vertically by a narrow neck that...

36525 ephemeris days and the Julian millennium of 365250 ephemeris days are used in astronomical calculations. Fundamentally, expressing a time interval...

Chicago Press. Explanatory Supplement to the Astronomical Ephemeris and the American Ephemeris and Nautical Almanac. London: Her Majesty's Stationery Office...

Moon's shadow cone passes closest to the centre of Earth; this is in (Ephemeris Time). The number of the saros series that the eclipse belongs to is given...

developed the ephemeris time scale, which had been adopted by the IAU in 1952 on a proposal formulated by Clemence in 1948, as an international time standard...

The geologic time scale or geological time scale (GTS) is a representation of time based on the rock record of Earth. It is a system of chronological...

the Gregorian calendar are used. For continuity with its predecessor Ephemeris Time, TCB was set to match ET at around Julian Date 2443144.5 (1977-01-01T00Z)...