What does an ephemeris provide?
An ephemeris records calculated positions of celestial bodies for specific dates and times. These positions allow a charting system to reconstruct a consistent astronomical reference for further observation.
Why does a professional system need it?
Accurate positions are the basis for angles, houses, aspects and later structural analysis. The calculation can be precise while interpretation still requires context, verification and human responsibility.
A calculation source is not a complete analysis
A reliable astronomical table supports reproducibility, but it does not decide what a person means, needs or should do. The international site keeps that boundary visible between data, method and professional judgement.