Word origin · etymology
Greek through Latin.
Greek ephemeris meant a diary or daily record; astronomical tables preserve the idea of positions recorded day by day.
How we know · epistemology
Numerical astronomical model
An ephemeris predicts positions from fitted observations and dynamical models. Agreement with independent observations tests the positional calculation, while its date range and model assumptions limit accuracy.
Connected concepts
Mentioned in 10 other entries
These links connect subjects and terminology. They do not establish a shared historical origin.
Sources & provenance
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