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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.]


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]


(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]


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


A table that shows the coordinates of a celestial body at various specific times.
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
References in periodicals archive ?
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.
The ephemeris was placed on the United Nations calendar in 1948.
The Greek-Latin title is Ephemeris belli Troiani, which can be translated as the journal of the Trojan war.
Orbit corrections are provided as along-track, cross-track and radial offsets to the Broadcast Ephemeris in an Earth-centered and Earth-fixed reference frame.
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.
Generate an ephemeris for your target and compare its output with what's predicted by your planetarium software.
Data is obtained from the JPL Horizons ephemeris generator, Occult 4.
To help satellite operators prevent collisions in space, the Space-Based Telescopes for Actionable Refinement of Ephemeris (STARE) mission, which will consist of a constellation of nano-satellites in low earth orbit, intends to refine orbits of satellites and space debris to less than 100 meters.
A De excidio Troiae historia, de Darete Frigio, a Ephemeris belli Troiani, de Dictis Cretense e a Ilias latina constituiram na idade media ocidental as unicas fontes de transmissao da gesta troiana, dada a indisponibilidade, na altura, dos textos homericos.
A new orbit was determined based on an observing arc of only 14 days, and an ephemeris was made available via JPL Horizons.
Timing ephemeris for the Crab pulsar is published monthly and available from Jodrell Bank monthly ephemeris (Lyne, A.