Word origin · etymology
Modern product name.
Swiss identifies the Swiss-developed Astrodienst ephemeris library; ephemeris is the older word for a table of celestial positions.
Astrodienst: Swiss Ephemeris programming manual ↗Merriam-Webster: ephemeris ↗
How we know · epistemology
Documented software implementation
The library documents positional algorithms and selectable conventions. Matching its output establishes implementation agreement; checking returned flags and independent references is still necessary before making an accuracy claim.
Connected concepts
Mentioned in 11 other entries
These links connect subjects and terminology. They do not establish a shared historical origin.
Sources & provenance
Use the citations beside each section to distinguish a calculation convention, a historical teaching and an editorial example.