Signs and houses describe each planet on its own. Aspects describe how the planets talk to each other. An aspect is a particular angle between two bodies in the chart, and the lines drawn across the middle of a chart wheel are aspects. This guide explains the five major aspects, how they are measured, and how Fate Hall finds them.
Angles on a circle
The zodiac is a circle of 360 degrees. To find the aspect between two planets, take the shorter distance between them around the circle — never more than 180 degrees — and see whether it is close to one of the key angles. The five "major" or Ptolemaic aspects come from dividing the circle by one, two, three, four and six:
| Aspect | Angle · orb | Character | Average per chart |
|---|---|---|---|
| ☌ Conjunction | 0° within 8° | Blending: the two energies act together | 2.5 |
| ⚹ Sextile | 60° within 5° | Harmony: an easy opening that rewards effort | 3.1 |
| □ Square | 90° within 7° | Tension: friction that pushes for action | 3.2 |
| △ Trine | 120° within 7° | Harmony: natural flow and talent | 3.0 |
| ☍ Opposition | 180° within 8° | Tension: a pull between two sides that seeks balance | 1.6 |
The "average per chart" column was worked out by running Fate Hall's own rules on a chart for noon on every day from 1950 to 2049. A typical chart has about thirteen major aspects in all, so a chart with none of a particular kind is quite normal.
Orbs: how close is close enough
Planets rarely sit at an exact angle, so astrologers allow a margin called the orb. Fate Hall uses eight degrees for the conjunction and opposition, seven for the square and trine and five for the sextile. Orbs are a convention rather than a law; some astrologers use wider orbs for the Sun and Moon and narrower ones for the outer planets. The closer an aspect is to exact, the more strongly it is felt.
| Planet A | Planet B | Distance | Aspect |
|---|---|---|---|
| 10° Aries | 14° Leo | 124° | Trine (4° from exact) |
| 28° Gemini | 3° Virgo | 65° | Sextile (5° from exact) |
| 5° Capricorn | 2° Cancer | 177° | Opposition (3° from exact) |
| 0° Taurus | 15° Gemini | 45° | None of the five |
Two things in these examples often surprise beginners. First, aspects are measured in degrees, not signs, so an aspect can link planets in signs that do not normally go together: 28° Gemini to 3° Virgo is a sextile at the edge of its orb, even though Gemini and Virgo are three signs apart. Second, not every angle counts. Forty-five degrees is a minor aspect called a semi-square, which Fate Hall does not draw.
What each aspect suggests
- Conjunction (0°). The two planets act as one. Whether that is easy depends on the planets: Venus with Jupiter is generous and warm; Mars with Saturn can feel like driving with the brakes on.
- Sextile (60°). A friendly opening. Sextiles show talents that grow when you use them — an opportunity rather than a gift.
- Square (90°). Friction between two needs that cannot both be satisfied at once. Squares are uncomfortable but productive: many astrologers see them as the engine of achievement in a chart.
- Trine (120°). Easy flow between planets usually in the same element. Trines describe natural strengths, which can also mean things you take for granted.
- Opposition (180°). Two planets facing each other across the chart. Oppositions often show up in relationships, where we meet one side of ourselves through another person, and they ask for balance rather than a winner.
On Fate Hall's chart wheel, green lines are the harmonious aspects (trines and sextiles) and red lines are the tense ones (squares and oppositions). Conjunctions are not drawn as lines because the two planets already sit side by side; they appear in the list below the chart.
The Moon and an unknown birth time
The Moon moves about thirteen degrees a day, so if your birth time is unknown its position could be off by up to six or seven degrees either way — almost a whole orb. Rather than show Moon aspects that might not exist, Fate Hall leaves them out when the birth time is blank. Aspects between the other planets change slowly enough that a noon chart is a fair guide.
Aspects in compatibility
The same angles are used to compare two charts. When one person's Venus trines the other's Moon, or their Mars squares the other's Saturn, astrologers read it as a theme in the relationship. The idea has a close parallel in BaZi, where the clashes and combinations between two people's branches play much the same role: harmonies bring ease and clashes bring friction that has to be worked with.
Common questions
Is a chart with many squares a bad chart? No. Tense aspects describe energy and motivation; charts with only trines can describe ease that never gets tested. Most astrologers look for a mix.
Why does another site list aspects Fate Hall does not? Some sites use wider orbs or include minor aspects such as the quincunx (150°) and semi-sextile (30°). Fate Hall keeps to the five major aspects so that the list stays short and readable.
Do the houses affect aspects? No. Aspects depend only on the zodiac positions of the two bodies, so they are the same in every house system.
Related guides
- The Planets and the Twelve HousesThe ten bodies of a birth chart and what they stand for, how long each stays in a sign, the twelve houses, and why Fate Hall uses whole sign houses.
- Sun, Moon and RisingWhat your Sun, Moon and Rising signs each describe, the twelve signs with their elements and rulers, and why the Moon and Rising signs need your birth time and place.
- Clashes and CombinationsHow the twelve branches combine and clash: the Three Harmonies, Six Harmonies, clashes and the Korean Yuan Jin, with a full lookup grid and the punishments and harms of classical texts.
- Mercury RetrogradeWhat retrograde motion really is, Mercury retrograde dates for 2025 to 2028 calculated and cross-checked, what astrologers associate with it, and retrograde planets in a birth chart.