Midpoint Trees API

From the birth moment and place, the endpoint takes the planetary longitudes and computes the midpoints between pairs, then searches the chart for any planet sitting on one of those midpoints — both the direct contact, where a body falls on the literal halfway degree, and the indirect contacts that the dial surfaces through its hard-aspect harmonics. For each planet it gathers the midpoint pictures it participates in into a midpoint tree, the structure Cosmobiologists write as A = B/C, and returns these under data.trees. Alongside, it detects the symmetries in the configuration — the points where the chart folds onto itself — and returns them under data.symmetries. The effect is to re-read the chart not as planets in signs and houses but as a web of equidistant relationships, which is exactly how Ebertin's school weighs influence: a planet completing a midpoint of two others is treated as the focal point where their combined meaning discharges.

curl -X POST https://api.astroway.info/v1/midpoint-trees \
  -H "X-Api-Key: aw_live_..." \
  -H "Content-Type: application/json" \
  -d '{
  "date": "1990-05-15",
  "time": "14:30:00",
  "timezoneOffset": 3,
  "latitude": 50.45,
  "longitude": 30.52
}'

{
  "ok": true,
  "data": {
    "trees": [
      {
        "planet": "Sun",
        "pictures": [
          "Moon/Venus",
          "Mars/Jupiter"
        ]
      }
    ],
    "symmetries": [
      "…"
    ]
  }
}

Use this endpoint when you are building for the Cosmobiology and Uranian audience, or for any interpreter that wants midpoint pictures rather than classical aspects — a 90° dial tool, an Ebertin-style report, or a chart analyser that ranks focal planets. The trees give you a ready structure to render and interpret: list the pictures a planet sits at the apex of and you have the core of a Cosmobiological delineation. Send the same birth data you used for the natal-chart endpoint and the midpoint structure will rest on the identical planetary positions, so the two views describe one chart. Because the output separates the per-planet trees from the chart-wide symmetries, you can choose to surface either the focused per-planet reading or the global picture of where the chart is structurally loaded.

The method follows Reinhold Ebertin's Cosmobiology as set out in The Combination of Stellar Influences, working in the 90° dial tradition where hard-aspect midpoints carry the weight. Planetary longitudes come from the Swiss Ephemeris (Astrodienst) WASM engine in the tropical zodiac, so the midpoints and trees rest on the same positions as the natal endpoints.