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n. pl. eph·e·mer·i·des (ĕf′ə-mĕr′ə-dēz′)
A table giving the coordinates of a celestial body at a number of specific times during a given period.

[Late Latin ephēmeris, from Greek, diary, from ephēmeros, daily; see ephemeral.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


n, pl ephemerides (ˌɛfɪˈmɛrɪˌdiːz)
1. (Astronomy) a table giving the future positions of a planet, comet, or satellite
2. (Astronomy) an annual publication giving the positions of the sun, moon, and planets during the course of a year, information concerning eclipses, astronomical constants, etc
3. (Library Science & Bibliography) obsolete a diary or almanac
[C16: from Latin, from Greek: diary, journal; see ephemeral]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ɪˈfɛm ər ɪs)

n., pl. e•phe•mer•i•des (ˌɛf əˈmɛr ɪˌdiz)
1. a table showing the positions of a heavenly body on a number of dates in a regular sequence.
2. an astronomical almanac containing such tables.
3. Archaic. an almanac or calendar.
[1545–55; < Latin ephēmeris day book, diary < Greek ephēmerís diary, account book]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


an astronomical almanac giving, as an aid to the astronomer and navigator, the locations of celestial bodies for each day of the year.
See also: Almanacs
-Ologies & -Isms. Copyright 2008 The Gale Group, Inc. All rights reserved.


A table that shows the coordinates of a celestial body at various specific times.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.ephemeris - an annual publication containing astronomical tables that give the positions of the celestial bodies throughout the year; "today computers calculate the ephemerides"
yearly, annual, yearbook - a reference book that is published regularly once every year
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
Due to satellite ephemeris errors, clock errors, tropospheric errors and many other factors, deviations often exist in satellite positioning, making it difficult to meet the needs of high-precision positioning [4].
Planning an observing session: The Astronomical Almanac Online lists ephemeris data for the calendar year.
Generally it is assumed that all error sources can be considered identical in both compared solutions and the differences in the final results are caused by differences in antenna calibration models (Baire et al., 2013).However, if the IGS14 model and ephemeris with clocks expressed in IGb08 are used, a systematic error occurred.
Jet Propulsion Laboratory (JPL) has been continuously supporting the maintenance and improvement of the ephemerides since the 1960s to satisfy the needs of high precision planetary ephemeris for the deep space navigation.
This of course relies on their providing timely ephemeris data with future manoeuvres included, and on the whole most members are good at doing this.
Masters and Grand Masters all over the world have read their ephemeris: Will man's best friend make the world a friendlier place in 2018?
IGS RTS has been provided since April 2013, and it contains orbit and clock corrections that can be applied to the broadcast ephemeris [1].
The Greek-Latin title is Ephemeris belli Troiani, which can be translated as the journal of the Trojan war.
For example, the ephemeris for the Moon, essential for astronomical determination of longitude, had to be computed on board because it was not available for the full duration of the voyage when they left Britain.
The five papers in English discuss three remarkable Arabic documents from the Heidelberg Papyrus Collection dating to the first-third/seventh-ninth centuries, the testimony of the papyri and literary sources concerning death dates in Umayyad stipends registers, an Arabic ephemeris for the year 931-932 CE, Nekloni (al-Naqlun) and the Coptic account book British Library Or.