Aspects in astrology: conjunction, square, trine, sextile, opposition

Aspects in astrology are the angles between planets on your birth chart wheel. Each one describes how two parts of your personality work together: they merge (conjunction), help each other (sextile, trine) or rub against each other (square, opposition). An aspect is measured in degrees, and the orb, the leeway allowed around the exact angle, decides whether it counts at all.

TL;DR: The five major aspects are the conjunction (0°), sextile (60°), square (90°), trine (120°) and opposition (180°); the Numato calculator also shows the quincunx (150°) and five minor aspects. No aspect is simply good or bad: in astrology, squares and oppositions describe two matters are in conflict and usually call for a decision or effort, while trines and sextiles describe ease that is easy to waste. The calculator allows a 10° orb for the four strongest aspects, 6° for the sextile and 3° or 2° for the rest.

What is an aspect in astrology?

A birth chart is a full circle of 360°, split into 12 signs of 30° each. Every planet sits at a specific degree on that circle. An aspect is the distance between two planets, measured around the circle, when it lands close to one of a set of standard angles. Those angles divide the circle into equal parts: halves (180°), thirds (120°), quarters (90°) and sixths (60°), and for the minor aspects also fifths, eighths and twelfths. A conjunction is 0°: two planets side by side.

In astrology each planet stands for a different part of life: the Sun for your sense of self, the Moon for emotions and needs, Mercury for how you think and talk, Venus for closeness and pleasure, and Mars for energy and action. An aspect tells you how two of those parts get along. That is why you read it as a pair: two planets plus the type of angle. The aspect name on its own says very little.

In the Numato calculator, aspects are formed by the Sun, the Moon and the eight planets from Mercury to Pluto, plus the Ascendant and the Midheaven (MC) when you know your birth time. Chiron, the North Node and Lilith (Black Moon) appear on the wheel without aspects. Positions are calculated astronomically from the NASA JPL ephemeris (DE440); the meanings come from astrological tradition, put into plain English.

The five major aspects and what they mean

The five major aspects are the classic set, often called the Ptolemaic aspects. Each one links signs in a fixed pattern, which is why tradition gives each a consistent character:

Tradition calls squares and oppositions hard or tense aspects, sextiles and trines soft or harmonious ones, and gives the conjunction the character of the two planets involved. "Hard" does not mean bad, and "soft" does not mean better. They are two different ways in which two parts of a chart affect each other.

Conjunction (0°)

A conjunction is two planets in the same place on the wheel, usually in the same sign. In astrology their functions fuse: one sets the other off, and it is hard to tell them apart. Is a conjunction good or bad? It depends on the planets. Tradition reads Venus with Jupiter as a softening combination and Mars with Saturn as a tightening one, where the drive to act meets caution and duty. A Moon–Venus conjunction joins the need for security with the need for closeness; a Sun–Mercury conjunction ties your sense of self to the way you think and speak. In everyday life, someone with the Moon conjunct Mars tends to turn a feeling into action before they have put a name to it.

Sextile (60°)

A sextile links signs two apart, so the elements complement each other: fire with air, earth with water. The two functions support each other, but only once you take the first step. Think of a sextile as an opening, not something that runs on autopilot. It also has a narrower orb than the other major aspects: 6° instead of 10°. In daily life, a Mercury–Venus sextile often shows up as an easy way of talking about feelings once the conversation has started.

Square (90°)

A square links signs three apart. They share a modality (cardinal, fixed or mutable) but belong to different elements. The two functions clash, and that friction forces action. Tradition adds that a square often becomes a person's greatest strength over time, because years of reconciling two conflicting needs teach you to do it well. A Sun–Saturn square, for example, describes someone who wants to be fully themselves and also feels the weight of duty very strongly. You might see it in someone who puts their own plans off for a long time and then, once they start, follows through more steadily than anyone else.

Trine (120°)

A trine links signs of the same element, such as Aries, Leo and Sagittarius, or Taurus, Virgo and Capricorn. The two functions cooperate without effort. That is exactly why tradition also sees a trap in it: a talent that comes easily is easy to take for granted and leave undeveloped. A trine does not start anything on its own; it needs a decision before it produces results. In daily life, a person with a Moon–Mercury trine can usually say what they feel without much trouble and may be surprised that others find it hard.

Opposition (180°)

An opposition is two planets facing each other from opposite signs. Two needs pull in opposite directions, and tradition says people often see one side of the pair in someone else: a partner, a boss, a parent. The goal is balance, not picking a side. A Moon–Saturn opposition, for instance, can look like a person who needs warmth and care but has carried other people's responsibilities since childhood. Once they notice the pattern, they can learn to ask for support without feeling they are letting anyone down.

The quincunx and the minor aspects

Quincunx (150°)

The quincunx, also called the inconjunct, links signs that have nothing in common: neither element nor modality. The two functions need constant adjustment. It is not one of the five Ptolemaic aspects, but the calculator treats it like one: it gets a short explanation ("Two matters fit together poorly and you have to keep reconciling them") and a solid line on the wheel. Its orb is narrow, though, only 3°. In daily life it tends to show up in habits and routines, where two needs fit together only if you keep tweaking the schedule.

The five minor aspects

Read the minor aspects after the major ones, as extra detail. The calculator lists them without an explanation and draws them on the wheel with a dashed line, so they are not mistaken for major aspects. Their orb is 3° at most, but the calculator keeps them under "Show weaker aspects": only aspects with an explanation appear straight away. Once you open the full list, which is still sorted by orb, a minor aspect can sit near the top; in the example below, a semi-square is third.

Orbs: how exact does an angle have to be?

Planets rarely sit exactly 90° or 120° apart. The orb is the allowed distance from the exact angle: inside the orb the aspect counts, outside it there is no aspect. The same word also describes how far a particular aspect is from exact, and the calculator shows that number next to every aspect. The smaller it is, the more weight the aspect carries in a reading.

The Numato calculator uses the orbs built into its calculation engine. The set is labeled "Standard (astro.com)" and matches the default style of astro.com:

The Ascendant and the MC are points calculated from the time and place of birth, not physical bodies, so when they pair with a planet they get half the planet's orb. The Ascendant and the MC do not form an aspect with each other. You can see the name of the orb set in your result under "Show calculation methods," next to "Aspect orbs." The settings let you change the house system and the zodiac, but not the orbs.

Why does another site show different aspects? Because every program picks its own orbs. With an 8° orb, a square that is 9° off disappears; with 10°, it stays on the list. Some programs give the Sun and the Moon wider orbs, and others also calculate aspects to Chiron, the nodes or Lilith. A list from another site can be shorter or longer even when the planet positions are identical. When you compare, start with the tight aspects: they depend least on the orb settings.

Orbs are counted in degrees, not signs, so an aspect can cross a sign boundary. In the example below, Venus sits at Capricorn 27°57′ and the MC at Taurus 0°09′. Capricorn and Taurus are both earth signs, which usually form a trine, yet the actual distance is just over 92°, so the calculator lists a square with a 2°11′ orb. It counts such aspects like any other. When you read one, keep in mind that each point is read in the style of its own sign.

How to read an aspect, step by step

1. Name both planets. Check what each one stands for: the Moon for emotions and needs, Mars for energy and action, Saturn for duties and limits.
2. Add the type of angle. A conjunction merges, a sextile or trine makes things easier, a square or opposition creates tension, and a quincunx needs adjusting.
3. Turn it into one sentence. Moon square Saturn: the need for comfort clashes with the sense of duty, which tradition reads as finding it hard to rest while something is unfinished; over time, that friction can teach you to set limits.
4. Check the orb. An aspect that is 1° from exact carries more weight than one that is 8° off.
5. Then look at signs and houses. The signs show the style of each planet, and the houses show the areas of life where the aspect plays out.

Start with aspects to the Sun, the Moon, the Ascendant and the MC, and with the tightest ones. Aspects between Uranus, Neptune and Pluto are shared by people born across several years: everyone born between 1990 and 1996, for example, has Uranus conjunct Neptune. Such aspects only become personal through their house or through a link to a personal planet. For how aspects fit into the rest of a reading, see how to read a birth chart step by step.

Next to every aspect, the calculator also shows its phase. "Applying" means the angle was getting more exact at the moment of birth, "separating" means it had already passed the exact point and was widening, and "exact" means it was less than one arcsecond off.

Example: the aspects in a chart from London

A fictional example: a person born in London on February 28, 1990, at 3:20 p.m. (GMT, UTC+0). The Numato engine, the same one the calculator uses, finds 34 aspects in this chart. The calculator shows the 9 strong ones (major aspects and quincunxes with an orb up to 3°) straight away and the other 25 under "Show weaker aspects (25)." Here are all nine, in list order:

The calculator gives orbs in degrees and arcminutes: 1°36′ is just over 1.6°. Once you show the weaker aspects, third on the full list is a semi-square from Jupiter to the Ascendant (0°43′), a minor aspect with no explanation. Under the list, the calculator shows three aspect patterns: "Minor Grand Trine: Sun, Neptune, Pluto — apex: Neptune," "Stellium · Capricorn: Venus, Mars, Saturn, Uranus, Neptune" and "Stellium · house 6: Venus, Mars, Saturn."

Mars conjunct Saturn (0°12′): good or bad? Mars sits at Capricorn 21°52′ and Saturn at Capricorn 22°05′, almost exactly together. This is the pairing tradition reads as tightening: energy and action fuse with duties and limits. On the plus side, that means stamina, patience and effort that is planned rather than rushed. The strain shows when caution takes over: anger that gets swallowed, or a start that waits for perfect conditions. Whether it reads as discipline or as frustration depends largely on whether the person finds an outlet for that drive.

Moon square Saturn (1°36′) and Moon square Mars (1°49′). The Moon sits at Aries 23°41′, about 90° from both planets in Capricorn. So the need for comfort and security clashes with the very pair described above. In everyday life this can look like someone who finds it hard to relax until the work is done, and who reacts sharply when feelings and obligations collide. Tradition sees the square as a driver: over the years, this friction can turn into the ability to look after yourself and your duties at the same time.

Look at the weaker list too: Venus conjunct Saturn (5°52′) and Venus conjunct Mars (6°05′) are there, all in Capricorn. They count, but with less weight than the tight conjunction at the top. That is the orb at work.

How the calculator shows aspects: wheel and list

Many programs show aspects in a grid, a triangular table where every planet has a row and a column. The Numato birth chart calculator does not use a grid. You will find the aspects in two places:

• On the chart wheel, as lines between planets inside the circle. The color shows the character: red lines are squares, oppositions, semi-squares and sesquiquadrates; blue lines are trines and sextiles; green lines are quincunxes and semi-sextiles; violet lines are quintiles and bi-quintiles. Minor aspects get a dashed line, and the more exact an aspect, the thicker its line. A conjunction has no line because the two planets sit side by side. The "Enlarge the wheel" button opens a bigger view.
• In the "Aspects" tab below the wheel, as a list sorted from the tightest aspect. Each row shows the two points and the aspect by name (planets and aspects also with their symbol), a short explanation for the major aspects and the quincunx, and underneath the orb and phase, for example "orb 1°36′ · separating." The strong aspects, meaning major aspects and quincunxes with an orb up to 3°, appear right away; the "Show weaker aspects" button reveals the rest, all minor aspects included, with their number in parentheses.

Below the list, under "Aspect patterns," the calculator lists figures formed by several planets: for a stellium it names the sign or house, and for a T-square and other patterns with an apex, the planet at the apex. When the birth time is approximate or unknown, an aspect that may have formed only during part of that window gets the note "depends on the exact time — it may not have occurred within the time range," and its line on the wheel is paler. Without a birth time there is no Ascendant or MC, so their aspects are missing too.

Aspect patterns: T-square, grand trine and more

An aspect pattern is a closed shape made by several planets linked by aspects. The calculator looks for patterns among the ten planets, using the same orbs as for aspects, and it leaves out aspects marked as depending on the exact time. That means a pattern can be built from aspects on the weaker list, and one planet can belong to several patterns.

T-square

A T-square is an opposition between two planets, plus a third planet square to both ends. Tradition sees it as the main source of tension in a chart. The planet at the apex, the one with two squares, points to the area through which a person resolves the conflict of the opposition. Tradition links it with plenty of motivation and ambition, provided the person finds an outlet. The calculator lists a T-square as three planets and names the apex right after them, for example "— apex: Saturn."

Grand trine

A grand trine is three planets linked by trines, usually in the three signs of one element, such as Cancer, Scorpio and Pisces. It describes great ease in the matters of that element: a talent that works on its own. Tradition also names the risk: comfort and low motivation when nothing demands effort. A grand trine with an opposition to one of its planets forms a kite, where the ease gets a direction.

Other patterns the calculator can show:

• Grand Cross — two oppositions joined by four squares; tension in four directions at once, read as practice in balancing many commitments.
• Yod — two quincunxes to one planet, joined by a sextile; the planet at the apex needs constant fine-tuning and marks an important area for growth.
• Kite — a grand trine with an opposition to one of its planets; the ease turns into a goal.
• "Mystic Rectangle" — two oppositions joined by trines and sextiles; the tensions come with ready ways to resolve them.
• Grand Sextile — six planets 60° apart; a rare pattern of many options that calls for choosing.
• Minor Grand Trine — a trine plus a planet sextile to both ends; talent with a practical outlet.
• Thor's Hammer — two sesquiquadrates to one planet, joined by a square; focused tension that pushes toward action.
• Stellium — three or more planets in one sign or in one house; a strong emphasis on one area of life. The calculator lists a stellium in a sign and a stellium in a house separately and adds the place after the name, for example "Stellium · Capricorn" or "Stellium · house 6."

Aspects in transits and between two charts

The same angles are used outside the birth chart. In transits, a planet in today's sky forms an aspect to a point in your birth chart, and tradition reads it as a period: a conjunction as the start of a new cycle in the matters of both planets, a square as a time of decisions and effort, an opposition as the peak of a cycle, and a trine as a time when things move more easily but still need to be started. In a synastry chart, which compares two birth charts, aspects are measured between the planets of two people. Tradition reads a conjunction there as a sense of togetherness in the matters of both planets, and a square as different styles that can irritate but also keep the relationship lively, which both people need to work on.

What aspects can't tell you

• They don't say what will happen. An aspect describes a tendency, how two parts of you work together, not events or other people's decisions.
• They aren't good or bad. A square can be a driver of growth, and a trine can be a talent nobody practices. What counts is what a person does with the pattern.
• They aren't read alone. One aspect doesn't decide someone's character. Signs, houses and the rest of the chart change its meaning.
• They don't depend on gender. Venus conjunct Mars means the same for every person.

Planet positions and the angles between them are calculated astronomically from the NASA JPL ephemerides. The meanings of the aspects are astrological tradition, described here in plain language.

Frequently asked questions

Is a conjunction good or bad?

Neither by default. A conjunction is read as two planets working as one, so its tone comes from the planets involved. Tradition reads Venus with Jupiter as softening and Mars with Saturn as tightening. The Numato calculator counts a conjunction up to 10° between planets and up to 5° between a planet and the Ascendant or MC. Its short explanation is the same for every pair: "Two matters merge into one and strengthen each other."

What does a square mean in astrology?

A square is a 90° angle between two planets. It describes two functions that clash and friction that forces action. It is not a verdict or a "bad" aspect: tradition holds that a square often becomes a person's greatest strength over time. In transits, a square marks a time of decisions and effort; between two charts, it shows different styles that both people need to work with.

What does a trine mean in astrology?

A trine is a 120° angle, usually between two signs of the same element. The two functions cooperate without effort, which tradition describes as easy flow and a talent that comes naturally. The catch is that a trine does nothing on its own: an easy talent is easy to take for granted. In transits, tradition reads a trine as a time when things move more easily if you make the first move.

Which aspect is the strongest?

In transits and between two charts, tradition sees the conjunction as the strongest contact. In a birth chart, strength depends above all on the orb: a square that is 1° from exact counts for more than a conjunction 9° wide. That is why the calculator sorts aspects from the tightest. The planets matter too: aspects to the Sun, the Moon or the Ascendant come before aspects between two slow outer planets.

Why does another chart site show different aspects?

Usually because of different orbs. One program allows a square up to 10° from exact, another up to 8° or 6°, so wide aspects appear on one list and not on the other. Programs also differ in whether they include Chiron, the nodes, Lilith and the minor aspects. The planet positions themselves should match; if they don't, check the birth time, place and time zone.

Can I see my aspects without a birth time?

Mostly, yes. Aspects between planets depend mainly on the date because planets move slowly. The exception is the Moon, which covers about 12–15° a day, so some of its aspects depend on the time. The calculator marks those with a note and a paler line on the wheel. Without a birth time there is no Ascendant or MC, though, so you won't see their aspects or the houses.

Check your own aspects with the birth chart calculator: enter your date, time and place of birth, then open the "Aspects" tab below the wheel. You'll see the list from the tightest aspect, with orb, phase and a short explanation, and the aspect patterns underneath.

This content is for educational purposes and supports self-reflection; it does not replace professional advice.