Aspect patterns: configurations in a birth chart

An aspect pattern, or configuration, is a group of three or more planets linked so that their aspects close into a geometric figure: a triangle, a cross, a rectangle. A single aspect describes a conversation between two planets. A pattern describes a system in which every planet affects all the others at once, and that system often becomes the main storyline of a chart.

Why a figure is more than the sum of its aspects

Take three planets. If they are joined by two squares and an opposition, you could read each aspect on its own and end up with three descriptions of tension. In the chart, though, they work together: pressure from two sides converges on one planet, and that planet becomes the point where the tension looks for an outlet. None of the three aspects has this property on its own. It belongs to the figure.

The same goes for harmonious patterns. One trine gives an easy link between two functions. Three trines closed into a triangle form a loop in which energy circulates without stopping, and that is a different quality altogether: stable, and at the same time prone to closing in on itself.

So astrologers read a pattern as a whole first (which figure, which modality or element, which planet carries the weight) and only then look at the individual aspects inside it.

The main configurations

T-square. Two planets in opposition and a third in square to both. The most common tense pattern. The third planet is called the apex, and it carries most of the load. In detail: T-square.

Grand cross. Four planets, two oppositions and four squares. In effect two T-squares laid over each other with no open corner. It is rare. More: grand cross.

Grand trine. Three planets, each trine the other two, usually in one element. The main harmonious pattern. In detail: grand trine.

Yod. Two planets in sextile and a third in quincunx (150°) to both. A pattern built on a minor aspect, often described as a sense of a particular task to be carried. In detail: yod.

Stellium. A cluster of planets in one sign or one house. Strictly speaking it is not a figure drawn with lines but a dense group of conjunctions, yet it is also read as one unit. In detail: stellium.

Three more figures are built from familiar parts and are read through them. A kite is a grand trine with a fourth planet added: it opposes one corner of the triangle and sextiles the other two, which gives the closed loop a direction. A mystic rectangle is made of four planets joined by two oppositions, two trines and two sextiles: the tension of the oppositions is balanced by soft aspects around the edges. A grand sextile is six planets 60° apart, two grand trines and three oppositions: the rarest of the figures.

Which orbs apply to patterns

There is no separate orb table for configurations. The working rule is that every side of the figure has to fit within the orb of its own aspect. If a T-square has an opposition with a 4° orb and one square at 9°, there is no T-square: there is an opposition and a separate, weak link.

Many astrologers use slightly tighter orbs for patterns than for single aspects, because the errors add up: three sides each 7° out make a triangle that looks visibly lopsided on the wheel. The tighter the figure, the more confidently it can be read. How orbs are set for individual aspects is explained on the orbs page.

How not to find patterns that are not there

The most common mistake is wanting to see a figure. A few checks help resist it.

• Check every side. A pattern exists only if all its aspects are present, not two out of three. Two squares without an opposition between their far ends are just two squares.
• Do not stretch the orb to fit. If the third planet is 11° from the point it would need to occupy, it is not an apex.
• Look at the signs. An out-of-sign pattern (say, a grand trine with one planet at 29° of a sign and another at 1° of the next) exists by degree, but its elements or modalities are mixed, and it reads differently.
• Treat non-planets separately. The Ascendant, Midheaven, lunar Nodes and Chiron can close a figure, but such a figure is better labelled as conditional and kept out of the centre of the reading.
• Watch the slow planets. Uranus, Neptune and Pluto stay in aspect to each other for years, and those aspects are shared by a whole generation. A figure made only of them describes an era more than a person.

Example: a chart without major patterns

Donald Trump's chart has no T-square, no grand trine and no yod, even though at first glance the material seems to be there. Its two oppositions (Sun to Moon and Moon to Uranus) lie on the same Gemini - Sagittarius axis, and no planet squares that axis. The Jupiter - Uranus trine is very tight, but there is no third corner in Aquarius. Cancer holds Mercury, Venus and Saturn: by the standard of those who count a stellium from three planets it is one, by the standard of those who require four it is not.

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