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Topocentric Ephemeris Study

A topocentric ephemeris study generates a table of topocentric planetary positions, as observed from a specific location on Earth's surface, at fixed time intervals over a date range. Its coordinate origin is fixed to topocentric, so the location you choose directly affects the computed positions. Like the other study types, it uses the shared configuration, generation, and results surfaces.

A completed Topocentric Ephemeris Study showing generated observer-relative planetary positions filling the ephemeris table.

Working with a Topocentric Study​

To create and generate a topocentric study:

  1. Create the study from the Ephemerides menu or the toolbar. See Create Study.
  2. Choose the observing location and other basic settings, set the date range, and pick the bodies and metrics to include.
  3. Click the Run button to generate the records.
  4. Review the results in the ephemeris table, then export them to CSV if you need them elsewhere.
caution

Because a topocentric study is computed from an observer's position on Earth's surface, the selected location shapes the results. Be sure to choose the correct location in the study's Basic Ephemeris Settings before generating.