Davison time and location midpoint
Build a chart at the midpoint of two birth instants and the spherical midpoint of two locations. The method is a symbolic relationship-chart convention.
Your inputs
Start with the example values, then replace them with your own. For tables, keep the vertical bar separators and use a dot for decimals.
Select a city to fill coordinates and the IANA time zone, or enter them manually. Verify historical local records; browser time-zone data can differ for old dates.
Astrology is for cultural exploration and entertainment. Do not base health, financial, relationship or major life decisions on these outputs. It has no scientifically established predictive validity.
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Result and workspace
Use the start button to open your result or activity.
How it works
The midpoint instant is the mean of both UTC timestamps. Normalize the sum of the two unit position vectors to obtain a great-circle midpoint; antipodal locations are rejected. Compute geocentric planetary positions and the ascendant at that instant and point.
Worked example
These sample results use the original example inputs in the form. They do not change when you edit your inputs; your own result appears in the workspace.
For the worked example, the birth time is treated as known. Use only a verified birth time for your own calculation.
- Midpoint latitude: 54.2545 degrees
- Midpoint longitude: -22.6744 degrees
- Ascendant longitude: 151.5896 degrees
| Celestial body | Longitude |
|---|---|
| Sun | 100.8183 |
| Moon | 109.5193 |
| Mercury | 107.1484 |
| Venus | 106.5774 |
Read the result carefully
Results depend on the values and assumptions shown above. Change one input at a time to see its effect. A blank or unavailable result means the data does not support a calculation; it is not zero.
Astrology is a cultural and entertainment framework, not a scientifically validated way to predict personality, health, relationships or future events. Astronomical positions do not validate astrological interpretations.
Data and calculation sources
Astronomy Engine 2.1.19 (MIT) · GeoNames (CC BY 4.0) · IANA
Geocentric tropical positions use Astronomy Engine. House options are equal and whole-sign only. City coordinates are approximate city centers from GeoNames, downloaded on 6 October 2026. Choose precise coordinates when available. Supported birth years: 1900–2100.