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Topocentric Aspect Ephemeris

A topocentric aspect ephemeris study generates a tabular listing of positional data and angular relationships between selected celestial body pairs as seen from a specific geographic location on Earth's surface at regular time intervals. This study type combines parallax-corrected body positions with aspect metrics describing angular separations between body pairs.

Creating a Topocentric Aspect Ephemeris Study​

Using the Menu​

  1. Click Ephemerides on the menu bar.
  2. Click Topocentric Aspect Ephemeris in the Ephemerides menu.

Using the Toolbar​

  • Click the Topocentric Aspect Ephemeris toolbar button.

A new topocentric aspect ephemeris study is added to the studies list and automatically selected.

Configuring the Study​

The configuration panel uses a tabbed interface for body and metric selections.

Topocentric Aspect Ephemeris configuration panel highlighting the coordinate origin set to Topocentric

Study Name​

Each study has an editable name that appears in the studies list.

Location​

Select a geographic location from the Location dropdown. For topocentric studies, the location determines both the time zone for date display and the observer position used in parallax corrections. Locations are managed through the Locations Editor.

Zodiac System​

Select the zodiac system from the Zodiac dropdown:

OptionDescription
TropicalPositions measured from the vernal equinox point
SiderealPositions measured from a fixed star reference

Reference Plane​

Select the reference plane from the Reference Plane dropdown:

OptionDescription
EclipticPositions measured along the ecliptic plane
EquatorialPositions measured along the celestial equator

Date Range​

Set the Start Date and End Date to define the time span for the ephemeris.

Time Interval​

Configure the time interval between records by setting the Interval value and selecting a Time Unit from the dropdown:

Time Unit
Seconds
Minutes
Hours
Days
Months
Years

Inner and Outer Bodies​

Click the Inner & Outer Bodies tab to access the body selections.

  • The Inner Bodies list contains all geocentric bodies: Ascendant, Medium Coeli, Descendant, Imum Coeli, Moon, Mercury, Venus, Sun, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto, Tenet, Lunar Apogee, Mean Apogee, North Node, Mean Node, Vesta, Juno, Ceres, Pallas, Chiron, and Pholus.
  • The Outer Bodies list contains all geocentric bodies except the cardinal points (Ascendant, Medium Coeli, Descendant, Imum Coeli).

Each selected inner body is paired with each selected outer body to produce aspect data. See Body Selection for details on selecting bodies in aspect studies.

Body and Aspect Metrics​

Click the Body & Aspect Metrics tab to access metric selections:

  • Body Metrics -- Control visibility of positional data columns. See Ephemeris Metrics.
  • Aspect Metrics -- Control visibility of aspect-specific columns:
Aspect MetricDescription
Cycle AngleThe angular position within the full 360-degree cycle between the body pair
PhaseThe current phase of the aspect relationship
SeparationThe angular distance between the two bodies

Generating the Ephemeris​

Once all parameters are configured, generate the ephemeris by clicking the Run button. See Generating Records for details.

Working with Results​

After generation completes, the ephemeris table displays positional and aspect data. You can:

tip

Save study configurations as ephemeris presets to quickly apply the same settings to new studies.