ephemeris
1
9.9
- noun
- /ɪˈfɛmərɪs/
- Specialized
:
efemérides
- If you find a comet near the predicted time of perihelion passage, you can construct an ephemeris from the orbital elements.
Examples
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"Is that an ephemeris?" he protested.
Fiction book (1994) -
The 12th-century Dresden Codex was the Maya version of our ephemeris tables for calculating the positions of the planets.
Academic text (1995) -
Why does the ephemeris keep getting lower and lower?
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Now that we have the comet's orbit, we will check the ephemeris and that will give us the distance between the comet and planet Earth.
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The Bristol accountant produced an ephemeris of dates and times for when the two spots would be in "conjunction" on the Central Meridian.
Academic text (2000) -
An ephemeris provides the positions of celestial bodies for astronomers to track their movements throughout the year.
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To plan our stargazing events, we regularly consult the ephemeris for accurate timings of celestial phenomena.
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The astronomer referred to the ephemeris to determine when the next solar eclipse would occur.
Synonyms
1
6.6
A book of maps that shows where stars and constellations are in the night sky
Compounds
- Archaic
Time measured by Earth's orbit, used for exact calculations of planet positions
Surface Forms
Etymology
Ephemeris comes from Greek parts epi- ('for' or 'on') and hemera ('day'), and it originally meant a daily record. Think of ephemeral ('short-lived'): an ephemeris gives the positions of stars and planets for each day, so it is a daily table or guide for astronomers and sailors.