Western Aspects API

Western Aspects

Returns the natal planetary aspects for a Western astrology chart — the angular relationships between planets in the tropical zodiac that form the interpretive backbone of Western natal analysis. Aspects reveal how the planets in a natal chart interact with and influence one another, and their nature (harmonious or challenging), orb (degree of exactness), and applying/separating status are central to understanding the dynamics of a person's character, life themes, and potential.

What This API Does

This endpoint accepts an individual's birth details and computes all significant angular relationships between the planets and key points in the tropical natal chart. It calculates the angular separation between every planet pair, determines whether that separation falls within the orb of a recognized aspect, identifies the aspect type, and assesses whether the aspect is applying (the planets are moving toward exactness) or separating (moving away). The scope of aspects returned is controlled by the aspectsType body parameter, which accepts all (major and minor aspects), major (only the five Ptolemaic aspects: conjunction, opposition, trine, square, sextile), or none (no aspects, useful when only planetary positions are needed from a combined endpoint). The house system and node type are configurable via the X-House-Type and X-Node-Type headers respectively.

Data Returned

The response provides a comprehensive natal aspect dataset for the tropical chart:

• Aspect list — the complete set of natal aspects between all planet pairs, filtered according to the aspectsType parameter, with each aspect entry identifying the two planets involved

• Aspect type — the name and symbol of each aspect (e.g., conjunction 0°, opposition 180°, trine 120°, square 90°, sextile 60°, and minor aspects such as semisextile, semisquare, sesquiquadrate, quincunx, quintile, biquintile when all is specified)

• Orb — the exact angular separation between the two planets and the deviation from the aspect's ideal angle, indicating how tight or wide the aspect is

• Applying or separating — whether the faster-moving planet is moving toward or away from exactness with the slower planet, a key factor in assessing the aspect's strength and timing relevance

• Aspect nature — whether the aspect is harmonious (trine, sextile), challenging (square, opposition), neutral/intensifying (conjunction), or mixed (minor aspects), providing an immediate qualitative reference

• Planet positions — the tropical sign, degree, and house placement of each planet involved in aspects, providing the positional context for each angular relationship

• Aspect strength indicators — assessments of each aspect's relative strength based on orb tightness and the planets involved, helping practitioners prioritize the most significant aspects in the chart

Main Use Cases

• Natal chart interpretation — computing the complete aspect grid for a Western natal chart as a core component of the interpretive analysis, identifying the key planetary dialogues that shape the individual's character, strengths, and challenges

• Astrology platforms and apps — powering natal chart aspect displays, aspect grids, and aspect tables that show users the angular relationships between their natal planets with orb and nature information

• Chart comparison and synastry preparation — using natal aspect data as the baseline for identifying which natal aspects are activated by a partner's planets in synastry analysis or by transiting planets in transit analysis

• Major aspect filtering — using aspectsType: major to retrieve only the five Ptolemaic aspects for simplified chart readings or for platforms that focus on the most widely recognized aspect set

• Full aspect analysis — using aspectsType: all to retrieve both major and minor aspects for advanced practitioners and platforms that incorporate the full spectrum of Western aspect theory

• Aspect pattern identification — using the complete aspect dataset to identify significant aspect patterns (Grand Trine, T-Square, Grand Cross, Yod, Kite, etc.) that involve three or more planets in a structured geometric configuration

• Applying aspect timing — using the applying/separating status of natal aspects to assess which planetary relationships were building toward exactness at birth, a factor some practitioners use to assess the developmental arc of natal themes

Key Functionality

• Accepts an aspectsType body parameter (all, major, or none) that controls the scope of aspects returned — major limits results to the five classical Ptolemaic aspects, all includes the full range of major and minor aspects, and none suppresses aspect output entirely for use cases where only positional data is needed

• Computes aspects in the tropical zodiac, consistent with the Western natal astrology framework, using the same planetary positions as the Western Planets endpoint

• Returns orb data for every aspect — both the exact angular separation between the planets and the deviation from the ideal aspect angle — enabling practitioners and platforms to apply their own orb tolerance thresholds or display orb tightness to users

• Identifies each aspect as applying or separating, providing the directional context that indicates whether a planetary relationship was intensifying or waning at the moment of birth

• Supports a configurable house system via the X-House-Type header, ensuring that the house placements of aspecting planets are calculated according to the practitioner's or platform's preferred house division method

• Supports configurable lunar node type via the X-Node-Type header (mean or true nodes), ensuring node positions used in aspect calculations reflect the caller's preferred node calculation method

• Returns aspect nature classifications (harmonious, challenging, neutral, mixed) alongside aspect type names, providing an immediate qualitative layer that supports both detailed practitioner analysis and simplified user-facing displays

• Accepts only birth details (date, time, latitude, longitude, and timezone) with no current location required, since natal aspects are based entirely on the birth chart

• Designed for localization — the Accept-Language header controls the language of aspect names, planet names, sign names, and all descriptive content in the response

• Serves as the primary aspect data endpoint for the Western natal astrology section of the API, providing the angular relationship dataset that underpins natal interpretation, synastry, transit analysis, and aspect pattern identification