The planetary orbs concern the area of influence of the astrological Aspects in number of degrees around the exact aspect.
Obviously, it’s always necessary to resituate an aspect in its cycle; a separative aspect will not be interpreted in the same way as an applying aspect.
Schematically, in the applying aspect, it’s more of a preparatory phase, preliminary to the action of the exact aspect, but often containing a greater tension or a form of effervescence.
The separative aspect has more value of “liberation”, integration, application, understanding, in relation to what happened during the exact aspect.
One can thus distinguish any aspect by its strength, the exact aspect being the strongest and most powerful, the applying aspect coming in 2nd position, then finally the separative aspect.
I will add another class of aspect, the “elemental” aspects which do not depend on the exact number of degrees but on the elemental colour of the planet according to the sign and the astrological element it occupies.
Thus, we can consider for example that 2 planets have a form of harmony of elemental conjunction, and of sign nature, as soon as they are in the same sign, whatever the degrees that separate them… and this applies to all signs, all aspects, allowing us to “bring the chart to life”, to think in terms of “zone of influence”, more than in a limited mathematical way (see my article on “Framing” in astrology).
One can also have with the orbs of planetary influence some so-called “dissociated” aspects, i.e. presenting an inconsistency in relation to their intrinsic nature : conjunction in different signs, square in harmonic elements (closer to the sextile or the trine), trine in inharmonic elements (closer to the sesqui-square or the square), etc. One must therefore nuance the astrological interpretation accordingly.
How many degrees should be retained for planetary orbs ?
Well, each astrologer has his own habits, his own ways of calculating the best possible orbs, and we cannot say that there is really a “miracle recipe”.
However, in the “astrological tradition” there are some basic rules to respect, first of all by taking into account the nature of the aspect itself (the conjunction is stronger and more important than the semi-sextile, so it must be valued like that in its orbs), then for example, the smaller the angle of the aspect, the more the exact Orb has to shrink (which is logical otherwise the aspects overlap), or again, taking into account the speed of a planet’s cycle, the slower it is, the closer it has to get to the exact aspect to have a real effective value, so the Orb of Influence has to be reduced accordingly.
The orbs are also different depending on whether one is analyzing a birth chart, or a Transits or Progressions chart.
In transits, slower planets need to have their orb reduced as a result of their speed to refine the forecasts.
In progressions, the time being “multiplied”, radically different orbs will be used, for example for the progressed Sun, its progression being 1° per year, an orb of 1° will already give a time range of 3 years (1 year in applying aspect, 1 year of exact aspect, 1 year of separative aspect).
It’s also necessary to keep in mind that things are not fixed, frozen, “abrupt”, and that a value in degrees does not do everything, the planetary influences can be felt in practice a little outside these orbs, even if your birth data are not quite accurate (the time in particular), this can shift for example the planetary entry into a house a few degrees…
Here are some standard values used by most astrologers for a birth chart :
- Conjunction, from 10 to 12°, raised to 15 sometimes, for the luminaries in particular (Sun / Moon)
- Opposition, from 10 to 12°, sometimes increased to 15°, for luminaries in particular too
- Quincunx, from 2 to 3°
- Sesquisquare, from 2 to 3°
- Trine, from 7 to 8°
- Square, from 5 to 6°
- Sextile, from 4 to 5°
- Semi-square, from 2 to 3°
- Semi-sextile, from 2 to 3°
For all other minor aspects (Quintile, Biquintile, Septile, Novile, etc) the planetary orb does not exceed 2°, and most often 1°.