Ephemeris Time (Noun)
Meaning
(astronomy) a measure of time defined by Earth's orbital motion; terrestrial time is mean solar time corrected for the irregularities of the Earth's motions.
Classification
Nouns denoting time and temporal relations.
Examples
- Astronomers use ephemeris time to calculate the precise positions of celestial bodies in the sky.
- The definition of ephemeris time was adopted as the fundamental time scale in astronomy in the early 20th century.
- The ephemeris time system replaced the earlier time-keeping system based on the Earth's rotation.
- By using ephemeris time, scientists can make accurate predictions about the timing of celestial events such as eclipses.
- ephemeris time is closely related to but distinct from terrestrial time and is sometimes used interchangeably in informal contexts.