Ephemeris-time


noun, Astronomy.
1.
time measured by the orbital movements of the earth, the moon, and the planets.
noun
1.
time that is based on the orbit of the earth around the sun rather than the axial rotation of the earth, one ephemeris second being 1/31 556 925.9747 of the tropical year 1900. It was used from 1960 to 1983 as an astronomical timescale but has been replaced by terrestrial dynamical time and barycentric dynamic time
ephemeris time
A highly accurate astronomical system for the measurement of time based in theory on the period of Earth’s orbit, but in practice relying on lunar observations and an accurate lunar ephemeris so as to not be subject to the irregularities of Earth’s rotation. The year 1900 CE is considered a standard year, containing 31,556,925.9747 seconds of ephemeris time.

Read Also:

  • Ephemeron

    [ih-fem-uh-ron, -er-uh n] /ɪˈfɛm əˌrɒn, -ər ən/ noun, plural ephemera [ih-fem-er-uh] /ɪˈfɛm ər ə/ (Show IPA), ephemerons. 1. anything short-lived or ephemeral. 2. ephemera, items designed to be useful or important for only a short time, especially pamphlets, notices, tickets, etc. /ɪˈfɛməˌrɒn/ noun (pl) -era (-ərə), -erons 1. (usually pl) something transitory or short-lived n. […]

  • Ephemeropteran

    [ih-fem-uh-rop-ter-uh n] /ɪˌfɛm əˈrɒp tər ən/ adjective 1. belonging or pertaining to the insect order Ephemeroptera, comprising the mayflies. noun 2. . /iːˌfɛməˈrɒptərən/ noun 1. another word for ephemerid adjective 2. of or relating to the Ephemeroptera

  • Ephemerous

    [ih-fem-er-uh s] /ɪˈfɛm ər əs/ adjective 1. .

  • Epher

    a calf. (1.) One of the sons of Midian, who was Abraham’s son by Keturah (Gen. 25:4). (2.) The head of one of the families of trans-Jordanic Manasseh who were carried captive by Tiglath-pileser (1 Chr. 5:24).

  • Ephes-dammim

    boundary of blood, a place in the tribe of Judah where the Philistines encamped when David fought with Goliath (1 Sam. 17:1). It was probably so called as having been the scene of frequent sanguinary conflicts between Israel and the Philistines. It is called Pas-dammim (1 Chr. 11:13). It has been identified with the modern […]


Disclaimer: Ephemeris-time definition / meaning should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional. All content on this website is for informational purposes only.