Applying and separating

Meaning

An aspect is a moment in a movement. While two bodies draw closer to the exact angle, the aspect is applying; once the angle has been exact and the gap starts to widen, it is separating. A trine with an orb of 2° can be either: still gathering, or already letting go.

Tradition gives the applying aspect more force. It describes something on its way, a matter still growing towards its peak; the separating aspect describes something that has happened and is being absorbed. In a birth chart, many astrologers read the difference gently: an applying aspect as a theme that keeps building and asks to be met, a separating one as a theme that feels more familiar and settles sooner.

As a rule the faster body applies to the slower one: the Moon applies to almost everything, while Pluto, the slowest planet, is almost always the one being approached. Direction matters as well as speed. A retrograde planet moving backwards can apply to a body behind it, and two planets moving towards each other, one direct and one retrograde, apply to each other at once.

The idea matters most where time matters: in horary astrology, which reads a chart cast for the moment a question is asked, and in transits and progressions, where an applying contact is one whose exact date is still ahead.

In practice

• The Moon at 10° Cancer and Venus at 13° Pisces are 117° apart. The Moon is faster and closing on the exact trine, so the aspect is applying; it will be exact in about six hours. With the Moon at 16° Cancer instead, the two are 123° apart, the exact trine came about six hours before, and the aspect is separating.
• In a horary chart, the Moon’s last separating aspect is read as what has just happened, and its next applying aspect as what comes next.
• A natal aspect that is still applying becomes exact some time after birth. In secondary progressions, where each day after birth stands for a year of life, that moment becomes the age at which the aspect is exact by progression.
• When the Moon will make no further major aspect before leaving its sign, it is void of course: nothing is left for it to apply to.

Origin and history

Application and separation are the working tools of horary astrology. In Christian Astrology (1647), William Lilly builds much of his judgement on them, and on the Moon’s in particular: an applying aspect between the planets that signify a matter shows that it will come about, while a separating one shows a matter past or falling away. He also names the ways an application can fail: refranation, when one planet turns retrograde before the aspect is exact; prohibition, when a third body reaches one of them first; frustration, when the slower planet joins another before the faster one arrives.

How Ulune calculates it

• In a birth chart, Ulune reads the phase from the two bodies’ speeds at the moment of birth, as Swiss Ephemeris gives them: if the gap to the exact angle is shrinking at that instant, the aspect is applying; if it is growing, separating. Speeds keep their sign, so retrograde motion counts with its direction.
• An exact aspect, or one whose gap is not moving at all, is neither, and the Table shows a dash.
• The angles, the Vertex and the lots have no motion of their own in a birth chart as Ulune casts it, so an aspect to them applies or separates by the other body’s motion alone.
• In synastry, each body moves at its own speed at its own birth. In transits and progressions the birth chart stands still and only the moving body counts. For the major aspects in those tables, Ulune also searches the ephemeris for the moment the aspect is exact, and calls it applying while that moment is ahead and separating once it has passed; a transit that draws close but turns back before it is exact is not shown as applying.
• The phase is shown in the Table, in its own column and as A or S in the grid, and on the wheel by the Applying / separating overlay: two small chevrons near the middle of each long aspect line, pointing towards each other while the aspect is applying and away from each other once it is separating.