Aspects in Astrology Explained: Trine, Square and More

Aspects in astrology are the angles between the planets in your birth chart. They show which parts of you work together, which pull in different directions and which blend into one. Signs and houses tell you what each planet is like and where it operates. Aspects tell you how the planets get on with one another. This guide explains the five main aspects, what orbs are, what each aspect tends to feel like and how to find them in your own chart.

What is an aspect in astrology?

An aspect is a specific angular distance between two planets, measured in degrees along the zodiac. A full circle is 360 degrees, and certain divisions of it (a whole, a half, a third, a quarter, a sixth) have been treated as meaningful since ancient times. When two planets sit at one of those distances, astrologers say they are "in aspect" and read them as linked.

Two things are worth knowing from the start:

• Aspects are measured by degrees, not by signs. Two planets can be in adjacent signs and still make a conjunction if they are close across the border.
• Aspects are not good or bad. Easy aspects can be lazy, and hard aspects often supply the drive that gets things done. Most useful chart readings come from the mix.

What are the five major aspects?

These are the aspects most astrologers use, and the ones that matter most for reading a birth chart.

The orbs above are the ones our own chart engine uses. Other astrologers use slightly wider or narrower ones, and that is a matter of taste, not of right and wrong.

What is an orb?

Aspects are rarely exact. An orb is the number of degrees of leeway you allow either side of the exact angle. If Venus is 3 degrees short of a perfect square to Saturn, that is a square with an orb of 3. The tighter the orb, the stronger the aspect is usually thought to be. A trine with an orb of 1 degree is a major theme in the chart, while one with an orb of 6 is a gentler background influence.

Many astrologers allow a wider orb when the Sun or Moon is involved, because they are the most prominent lights in the chart. Our reports do this too: two extra degrees for the Sun and Moon on most aspects, and one extra for the sextile. An aspect right at the edge of its orb should be read lightly.

What does each aspect mean?

Conjunction: the planets merge

A conjunction is when two planets sit at roughly the same degree. They act as one, so their qualities mix and amplify each other. The Sun conjunct Mercury, for example, tends to make thinking and identity hard to separate. Conjunctions are powerful but not automatically comfortable, because you cannot easily use one planet without the other. How it feels depends on the planets involved.

Sextile: friendly opportunities

A sextile is 60 degrees, two signs apart, and links signs of compatible elements (fire with air, earth with water). It is a gentle, cooperative aspect. The two planets can help each other, but the link tends to be an opening, not an automatic gift: you often have to make use of it. Many people have several sextiles they barely notice until they put them to work.

Square: friction that drives you

A square is 90 degrees, three signs apart, and joins signs of the same modality but incompatible elements. This is the classic aspect of tension. The two planets want different things, and the discomfort pushes you to act. Squares are often the source of ambition, restlessness and growth, and people with strong squares are often hard workers. The challenge is to avoid swinging between the two sides instead of finding a way to use both.

Trine: natural flow

A trine is 120 degrees, four signs apart, and links signs of the same element. The planets support each other easily, so the talent or ease it describes feels natural, even invisible to you. The downside of a trine is that things that come easily are easy to take for granted, so it can go unused. A chart with only trines and no challenges tends to be comfortable but a bit unmotivated.

Opposition: the balancing act

An opposition is 180 degrees, six signs apart, with the two planets facing each other across the chart. It is felt as a see-saw: you notice one side strongly, then the other, and may project one onto other people. Oppositions often show up in relationships, where someone else seems to carry the quality you have not yet owned. The work here is balance and integration, not choosing a side.

How do I spot aspects in my chart?

You can find aspects in two ways. On a chart wheel, aspects are the coloured lines running across the middle, joining pairs of planets. Many charts also include an aspect grid, a triangular table where each box shows the symbol of the aspect between two planets.

To check one by hand, work out each planet's position in degrees of the full zodiac (Aries 0 to Pisces 360, so Taurus 10 degrees is 40) and subtract. If the difference is close to 0, 60, 90, 120 or 180, you have an aspect. If you are over 180, subtract from 360 instead.

Where to start in your chart:

• Look at the tightest aspects first. An orb under about 3 degrees stands out.
• Prioritise the personal planets. Aspects involving the Sun, Moon, Mercury, Venus and Mars describe your daily temperament, while those involving Jupiter to Pluto are shared with a whole generation unless they touch your personal planets.
• Notice patterns. Several aspects among the same planets form a theme, and a Moon that is squared by two planets matters more than a single aspect.

The aspects work together with the rest of the chart, so it helps to know how everything fits. Our guide to how to read your birth chart walks through the order to read it in, and astrology houses explained covers the area of life each planet falls in.

What about minor aspects?

Astrologers also use minor aspects such as the semi-sextile (30 degrees), semi-square (45 degrees), quincunx (150 degrees) and sesquiquadrate (135 degrees). They have narrower orbs, usually around 2 or 3 degrees, and are generally treated as supporting detail. When you are starting out, the five major aspects give you most of the picture. Our engine focuses on the five major aspects as well.

Which aspects does a natal chart report cover?

A chart can hold dozens of aspects, and reading them all makes a confusing report. Our Natal Chart Report picks the eight key aspects in your chart, the tightest and most meaningful ones, and explains each in plain language, alongside your Big Three, planets, Midheaven and element balance. Positions use the tropical zodiac and are accurate to the arcminute. If you are curious how aspects work between two people's charts, see synastry explained.