Western core calculations

Core Western endpoints derive deterministic natal factors from an existing Western chart. All routes require charts:read and return 422 for Vedic or otherwise non-Western charts.

House-dependent routes accept house_system=placidus|whole_sign|equal. The override recalculates the same birth moment and location for that response only; it does not mutate the stored chart.

Aspects — GET /v1/western/charts/{id}/aspects

Returns natal aspects between Sun-Pluto, Ascendant, and Midheaven.

curl -H "Authorization: Bearer $TOKEN" \
  "https://api.astrolinkers.com/v1/western/charts/$CHART/aspects"

[
  {
    "planet_a": "sun",
    "planet_b": "moon",
    "aspect": "trine",
    "category": "major",
    "tone": "harmonious",
    "exact_angle": 120.0,
    "orb_degrees": 1.1842,
    "max_orb_degrees": 9.0,
    "strength": 0.8684,
    "is_applying": true
  }
]

Field	Type	Notes
aspect	enum	conjunction, opposition, trine, square, sextile, quincunx, semisextile, semisquare, sesquiquadrate.
category	enum	major or minor.
tone	enum	harmonious, dynamic, or neutral.
orb_degrees	float	Absolute distance from exactness.
max_orb_degrees	float	Effective allowed orb after luminary/angle handling.
strength	float	1 - orb / max_orb, clamped to [0, 1].
is_applying	bool	Whether next-day motion reduces the orb.

Dignities — GET /v1/western/charts/{id}/dignities

Essential dignity profile for Sun-Pluto.

[
  {
    "planet": "sun",
    "sign": "aries",
    "degree_in_sign": 10.0,
    "dignity": "exaltation",
    "rulers": ["mars"],
    "triplicity_rulers": ["sun", "jupiter", "saturn"],
    "term_ruler": "venus",
    "face_ruler": "sun",
    "is_in_rulership": false,
    "is_in_exaltation": true,
    "is_in_detriment": false,
    "is_in_fall": false,
    "score": 8
  }
]

Dignity states:

rulership · exaltation · triplicity · term · face · peregrine · detriment · fall

Notes:

• Terms use the Egyptian bounds.
• Faces use the Chaldean decan sequence.
• Scorpio, Aquarius, and Pisces include modern co-rulers in rulers, while time-lord/profection logic uses traditional rulers.

Balance — GET /v1/western/charts/{id}/balance

Weighted element, modality, hemisphere, quadrant, and house emphasis.

Optional query:

house_system=placidus|whole_sign|equal

{
  "elements": [
    { "kind": "element", "name": "fire", "weight": 5.0, "percentage": 0.3125, "planets": ["sun", "mars"] }
  ],
  "modalities": [
    { "kind": "modality", "name": "cardinal", "weight": 4.0, "percentage": 0.25, "planets": ["moon"] }
  ],
  "hemispheres": [],
  "quadrants": [],
  "house_types": [],
  "house_placements": [
    { "planet": "sun", "house": 6, "sign": "sagittarius" }
  ],
  "dominant_element": "fire",
  "dominant_modality": "mutable"
}

Weights are intentionally not simple counts: luminaries carry more weight than personal planets, social planets, outer planets, and angles.

Patterns — GET /v1/western/charts/{id}/patterns

Detects major natal configurations:

• stellium by sign and by house;
• grand trine;
• T-square;
• grand cross;
• yod;
• kite;
• bowl and bucket distributions.

[
  {
    "kind": "grand_trine",
    "planets": ["sun", "venus", "mars"],
    "signs": ["aries", "leo", "sagittarius"],
    "houses": [],
    "strength": 0.8125,
    "description": "Grand trine"
  }
]

Summary — GET /v1/western/charts/{id}/summary

Aggregates the lower-level factors into a compact deterministic feature summary for product UI and LLM grounding.

Optional query:

house_system=placidus|whole_sign|equal

{
  "chart_id": "019e32b5-...",
  "aspect_count": 42,
  "major_aspect_count": 21,
  "strongest_aspects": [],
  "dignity_highlights": [],
  "balance": {},
  "patterns": [],
  "lunar_phase": {
    "name": "balsamic",
    "angle_degrees": 331.42,
    "illumination": 0.061
  },
  "retrogrades": {
    "planets": ["mercury"],
    "count": 1,
    "has_personal_retrograde": true
  },
  "themes": ["dominant_fire", "dominant_mutable"]
}

Lunar phase names:

new · crescent · first_quarter · gibbous · full · disseminating · last_quarter · balsamic

Houses — GET /v1/western/charts/{id}/houses

Returns deterministic house vectors for product UI and LLM grounding.

Optional query:

house_system=placidus|whole_sign|equal

[
  {
    "house": 1,
    "sign": "leo",
    "ruler": "sun",
    "planets": ["sun"],
    "angularity": "angular",
    "topics": ["identity", "body", "self_direction"]
  }
]

Field	Type	Notes
house	int	House number, 1..12.
sign	enum	Sign on the house cusp.
ruler	enum	Traditional sign ruler.
planets	array	Core Western planets occupying the house.
angularity	enum	angular, succedent, or cadent.
topics	array	Stable product topic labels.

Dispositors — GET /v1/western/charts/{id}/dispositors

Follows traditional sign rulers from each core planet until the chain reaches a final dispositor, an absent ruler, or a loop.

[
  {
    "planet": "moon",
    "links": [
      {
        "planet": "moon",
        "sign": "taurus",
        "ruler": "venus",
        "ruler_sign": "libra",
        "is_final": false
      }
    ],
    "final_dispositor": "venus",
    "is_mutual_reception": false,
    "loop": []
  }
]

Two-planet loops are flagged as is_mutual_reception.

Antiscia — GET /v1/western/charts/{id}/antiscia

Mirrors core planets across the solstice axis for antiscion points and across the equinox axis for contra-antiscia.

[
  {
    "planet": "sun",
    "sign": "aries",
    "longitude": 10.0,
    "antiscion_longitude": 170.0,
    "antiscion_sign": "virgo",
    "contra_antiscion_longitude": 350.0,
    "contra_antiscion_sign": "pisces"
  }
]

Lots — GET /v1/western/charts/{id}/lots

Returns the seven Hermetic Lots / Arabic Parts with day-night formulas: Fortune, Spirit, Eros, Necessity, Courage, Victory, and Nemesis.

[
  {
    "name": "fortune",
    "planet": "moon",
    "longitude": 330.0,
    "sign": "pisces",
    "degree_in_sign": 0.0,
    "house": 12,
    "formula": "ascendant + sun - moon",
    "is_day_formula": false,
    "theme": "received_condition"
  }
]

The response includes the exact formula string used, so product UI and LLM grounding can stay auditable.

Fixed stars — GET /v1/western/charts/{id}/fixed-stars

Returns close conjunctions from core planets and angles to a compact fixed-star catalog. The catalog is precessed from J2000 before contacts are checked.

Query param	Type	Required	Notes
max_orb_degrees	float	no	0.1…2.0; defaults to 1.0.

[
  {
    "star": "regulus",
    "catalog_version": "western-fixed-stars-2026-05-30",
    "longitude": 150.2,
    "sign": "virgo",
    "magnitude": 1.35,
    "planet": "sun",
    "planet_longitude": 150.0,
    "house": 10,
    "orb_degrees": 0.2,
    "max_orb_degrees": 1.0,
    "nature": "mars_jupiter",
    "keywords": ["leadership", "status", "courage"]
  }
]