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A Brief Guide to the Aspects

in Traditional Astrology


Sue Ward

The major and minor categories of aspects derive from the innovative work of Johannes Kepler. Previously only the sextile, square, trine and opposition were allowable aspectual relationships. The conjunction is not strictly an aspect since this is a bodily joining of two or more sets of planetary characteristics, but generally included under this heading.

All earlier authorities had taught that the signs themselves had to be in relationship for an aspect to hold good. Aspects had to divide exactly into 360 degrees, automatically disallowing those from signs disjunct from the ascendant. This had changed somewhat by medieval times to allow the so-called dissociate aspect, where planets are in aspect but their signs are not.

The traditional method, as currently practiced, derives mainly from the orthodox system of the Renaissance period. Its leading practitioner was William Lilly and apart from one instance (a semisextile), Lilly used the major aspects exclusively in his horary instruction and judgements. He used the minor aspects quite widely for nativities, but only as points to which directions were made to ascertain future events.

The Orbs

Any promised event will occur at the moment of the exact aspect. There is, however, a period both before and after this exactitude when the aspect makes its presence felt. This is commonly known as the period when the planets are within orb of aspect. When a traditional astrologer mentions orbs, though, she or he alludes to the planetary orbs. The orb has always belonged to the planet, not the aspect. Although in practice this often makes little difference, it is a concept that is fundamental to a true understanding of astrology.

The planets were held to emit rays which carried the 'nature', 'virtue' or 'influence' of that planet, what might now be called its characteristics. These rays, its orb of influence, surrounds the planet like an aura and the size, in degrees of longitude, varies according to the planet. When this orb comes into contact with that of another planet application begins. Looking at the orbs and moieties, it is immediately apparent that there is another problem with using the minor aspects: it is not practicable to use the planetary orbs. In the modern system, too, only a one to two degree orb of aspect is allowed when dealing with the minors. If it were necessary, such an orb could also be used in traditional astrology, although it is more usual to address them only when they are exact.

The orbs are approximate and this seems to be because there was some debate about them. In Classical astrology the emphasis was on the sign relationships and planets would often be considered to be in aspect when they were completely wide of the mark, but in the correct sign. For example, Jupiter in 2 degrees Aries and Mars in 20 degrees Sagittarius would be considered to be in platick trine. The use of orbs developed slowly and often varied according to the author.

Our forbears were much less concerned with absolute precision than we are. Their interest was in judging a chart according to the information it offered, not so much according to the rules and regulations forced upon it. Certainly Lilly frequently exhorted his students to use art and discretion or rather, astrology and commonsense.

Minor aspects cannot show major events, only descriptions or added information. The main tale will be told by the seven planets and the major aspects. Horary offers the best opportunity of testing any technique or theory and does not rely on aspects alone to give its answer, but it is vital that they are properly understood.

The New Planets

The accepted orbs and moieties of each of the planets exclude the trans-Saturnians. They have not been attributed orbs and are usually dealt with (if at all) within the 17' of arc exactitude. This is because the ancient authorities dealt with the planets and stars they could actually see; the fact that they sometimes described their effects in terms of rays or beams confirms that, as does use of techniques such as translation and collection of light. Since the new planets cannot be seen with the naked eye, they could have no rays. Having no rays means no orb of influence, in much the same way as the lunar nodes and the Part of Fortune have no orbs. So they can only be aspected. Bear in mind that astrology deals with the heavens as they appear to the Earthly observer.

Since the trans-Saturnians play no part in the traditional scheme because of their recent discovery, it is pointless for me to discuss them further within the present context. Many traditional astrologers use them widely, others use them occasionally, some not at all. They each have their own reasons for this and such explanations are not within the remit of this article.

Application and Separation

The phrase 'applying to aspect', that is, applying to the perfect or exact aspect, is often misused to mean moving towards another planet by aspect, even though they have yet to make contact through their orbs. Claudius Dariot, much respected by 17th century astrologers, writing in the 16th century says this:

The Application happeneth when as the Circles or beames of the Planettes come to joyne togeather by a corporall Coniunction, or by aspecte of the one halfe of their Deamiters.

The further importance of using this phrase correctly will be demonstrated below in the explanation of the void of course condition.

Application shows the possibility of an event, therefore the two planets capable of bringing this about need to have some relationship - they have to be in contact through their orbs.

After perfection, that is 17' of arc after exactitude, separation begins. It ends when the planets have no further contact through their orbs. In fact, to use the word 'orb' like this is incorrect. The orb is the overall distance of the planet's influence, on a chart we look at this in two dimensions and see part of the orb in front of the planet and part behind. Those parts are halves of the overall orb and known as the moeities. To understand application you need to know the diurnal motions of the planets. Usually the average will do for most cases, but although we know that Mercury is usually faster than Venus, there are times such as during retrogradation, when the reverse is true. So, the faster planet applies to the slower. When a planet applies to another which is retrograde, mutual application occurs, since the retrograding planet moves backwards to meet the first.

Void of Course

So, in order to be able to say that a planet is either applying to or separating from another, the moieties of both must be in contact. When there is no such contact the planet is void of course. Referring again to Dariot: ...voyd or without course is when a planet doth not apply to any other during the time that he tarrieth in that signe and then he is saide to have his course and motion voyd.

For example, Saturn is at 7 Pisces, the Moon is at 8 Gemini and Mercury is at 27 Libra. So the Moon has just separated from Saturn (Moon's moiety: about 6. Saturn's moiety: about 4. Joint moieties: about 10.) The Moon's next major aspect - minor aspects cannot prevent a planet from being void of course - is a trine with Mercury. To see if this is actually an application the two moieties are added together. The Moon's moiety is about 6 and Mercury's moiety is 3, so when they are about 9 apart application will begin. In this example they are about 19 apart and so there is no application; the Moon is void of course, it applies to no other planet from its present position.

As far as interpretation is concerned, the void of course Moon is often taken to mean that nothing will happen in regard to the matter under investigation. This is much different to the answer that might have been given had the trine to Mercury been taken into consideration. For example, suppose the question were one of marriage and Mercury represented the person enquired after; the Moon moving to trine Mercury might be taken to mean that the marriage would go ahead. Whereas accepting the Moon correctly as void of course would indicate that the marriage would not go ahead. The vast difference in the outcome demonstrates how useful horary can be for proving or disproving an astrological technique.

Dissociate applications

By this I mean when the Moon, say, is applying to the aspect of another, but the aspect can perfect only after the Moon has changed sign. This is a valid application and the Moon cannot be designated void of course. It seems, however, to have been disallowed up to the medieval period which is understandable considering the importance of the sign relationship. Later, though, ibn Ezra disputed this doctrine:

If the two planets should be in two signs and each one of them should be in the force of the other's body, they must not be said to be in conjunction, because they are in different signs. That is the opinion of the ancient scientists, but I, Abraham, the compiler of this book, disagree with them;

It has been said that he refuted this in a later work, whether he did or not is hardly relevant to how the attitude to the dissociate aspect had developed by the 17th century.

Certainly Lilly used this method freely with no detriment to his judgements. My discovery, or rather, redefinition of these traditional techniques has improved the reliability of my horary practice enormously. Perhaps you might like to check your own horaries, particularly those you discarded because you thought the Moon was void of course.


Application means to be within orb of and approaching a slower moving planet by major aspect. Separation means to be withdrawing from a slower planet whilst still being within orb of major aspect (Lilly and other authors are less careful about this latter, though). Void of course means that the planet is not applying to another, that is, it is not within orbs of and approaching another planet. If the aspect must be perfected by crossing into another sign and it is within orbs, the planet is not void of course.

These definitions conform to traditional orthodoxy and throw a new light on current researches into the Renaissance method.


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22 February 1996
1995 Sue Ward

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