Morphemeris DocsAspects
Angular relationships between celestial bodies, with types, orbs, and applying/separating dynamics.
Aspects
An aspect is a specific angular relationship between two celestial bodies as seen from Earth. Aspects are the primary tool for interpreting how planets interact in a chart — they describe the geometry of the sky at a given moment.
How aspects work
Every pair of bodies has an angular separation (0°–180°). When that separation is close to a recognized angle, the two bodies are said to be "in aspect." The tolerance — how close is close enough — is called the orb.
For example, if the Sun is at 15° Aries (15° ecliptic longitude) and the Moon is at 134° (14° Leo), their separation is 119°. A trine aspect is 120°, and the default trine orb is 8°. Since 119° is within 8° of 120°, the Sun and Moon are in a trine with an orb of 1°.
Aspect types
Major aspects (the default set)
These are the 7 aspects computed by default when you call /v1/aspects or /v1/natal-chart:
| Aspect | Angle | Default orb | Tradition |
|---|---|---|---|
| Conjunction | 0° | 8° | Bodies are in the same place — fusion, intensity |
| Opposition | 180° | 8° | Bodies face each other — tension, awareness, polarity |
| Trine | 120° | 8° | Harmonious flow — ease, talent, sometimes complacency |
| Square | 90° | 7° | Friction — challenge, drive, internal conflict |
| Sextile | 60° | 6° | Opportunity — cooperation, requires effort to activate |
| Quincunx | 150° | 2° | Adjustment — disconnect between signs with nothing in common |
| Semisextile | 30° | 2° | Mild tension — adjacent signs adapting to each other |
Minor aspects
Available by specifying the aspects parameter explicitly:
| Aspect | Angle | Default orb | Notes |
|---|---|---|---|
| Semisquare | 45° | 2° | Mild friction, irritation |
| Sesquiquadrate | 135° | 2° | Similar to semisquare, slightly more intense |
| Quintile | 72° | 1° | Creative talent, unique ability |
| Biquintile | 144° | 1° | Creative expression, mastery |
| Septile | 51.43° | 1° | Spiritual or fated quality |
| Novile | 40° | 1° | Completion, spiritual attainment |
| Decile | 36° | 1° | Growth, self-improvement |
Orbs
The orb is the maximum allowed deviation from the exact aspect angle. A tighter orb (smaller number) means the aspect is closer to exact and generally considered stronger.
The API uses sensible defaults (shown in the tables above), but you can override them with the orb parameter to set a single orb for all aspects.
Applying vs. separating
An aspect can be applying (the bodies are moving toward exactitude) or separating (moving away from it). Applying aspects are traditionally considered stronger — the energy is building rather than fading.
Set applying=true on the request to include this flag in the response.
Parallels
Parallels are a separate type of aspect based on declination (how far north or south of the celestial equator a body is) rather than ecliptic longitude:
- Parallel — Two bodies at the same declination (equivalent in strength to a conjunction)
- Contraparallel — Two bodies at equal but opposite declinations (equivalent to an opposition)
Parallels use a tight default orb of 1°. Request them with parallels=true.
Using aspects in the API
/v1/aspects— Standalone aspect computation (1 credit)/v1/natal-chart— Includes aspects as part of the full chart (2 credits)/v1/synastry— Inter-chart aspects between two people's bodies (3 credits)