△ Free Grand Trine Calculator: Is There One in Your Chart?

Umbriel's free Grand Trine calculator checks your birth chart for three planets forming an equilateral triangle, and shows which planets form it, their element and how close each trine is to exact.

A Grand Trine is three planets spaced about 120° apart round the zodiac, so each is trine to the other two and the three joined make an equilateral triangle. Because 120° is a third of the circle, the planets usually land in signs of one element: a fire Grand Trine in Aries, Leo and Sagittarius, an earth one in Taurus, Virgo and Capricorn, and so on. Umbriel names the element when the three share one and says so when they do not.

A trine is the angle astrologers read as ease, two planets in the same element speaking the same language. A Grand Trine closes the circuit, so nothing in the shape resists. The classic reading is a natural talent or comfort that can run on autopilot, and the classic caution is that nothing in the shape makes it get used. The lesson on aspect patterns walks through that idea.

Not every triple of trines is a clean one. Three planets can each be 120° from the others and still straddle two elements, when one sits at the very start or end of a sign. Some astrologers read that as weaker. Umbriel counts it, because the angles are right, and marks it so you can decide.

Each aspect is judged on its own orb. Nothing is added up, the Sun and Moon get no extra orb, and the limits are the same for every planet. Every limit is at or below the orb the chart's own aspect lines use, so each aspect in a figure is also a line on your chart. Umbriel never widens an orb to produce a result. If nothing fits, the answer is none, and a figure that is only just outside an orb is shown on its own, marked as not counted.

In Umbriel's collection of 4,135 famous charts (born 1600 to 2014), cast for noon on the birth date with the Sun to Pluto and the Moon left out, because the collection holds no birth times, 139 have at least one Grand Trine at these orbs: 3.4 per cent.

At the wider orbs of the chart's own aspect lines (opposition 8°, trine and square 7°, sextile 5°, quincunx 3°), 173 would have one: 4.2 per cent instead of 3.4. The orb choice alone moves the answer, which is why this page prints its own.

That is a count of famous people, not of births: the collection leans towards the twentieth century, and because Jupiter to Pluto move slowly, a whole birth cohort can share a figure made of them. A fair sample of everyone would differ.

Umbriel casts the ten planets, Sun to Pluto, for the moment of birth with the same engine as the rest of the app, then tests every combination of planets against the shape. A figure counts only if every aspect in it is inside its own orb: trine 6°. Each aspect is judged on its own orb. Nothing is added up, the Sun and Moon get no extra orb, and the limits are the same for every planet. Every limit is at or below the orb the chart's own aspect lines use, so each aspect in a figure is also a line on your chart.

The Ascendant and Midheaven are left out because they need an exact birth time and place; the lunar nodes, Chiron and the asteroids are left out to keep one clear rule. Adding any of them would find more patterns, and every pattern found that way depends on a choice that is not made here. Umbriel never widens an orb to produce a result. If nothing fits, the answer is none, and a figure that is only just outside an orb is shown on its own, marked as not counted.

The place of birth does not matter for this, because the planets stood at the same longitudes wherever you were born. What turns your clock time into a moment is the time zone, which is why the form asks for a UTC offset and not a city. Use the offset that was in force on the birth date, daylight saving included. The place of birth does not change where the planets were, so Umbriel asks for the time zone, not the town.

With no birth time the Moon is the first thing to move. The Moon travels about 13° a day, so with no birth time it could have stood anywhere in a span of about 26°, and any figure that includes it depends on the hour. The Ascendant and Midheaven need an exact time and place, so Umbriel does not use them here at all.

A real chart: Jennifer Lawrence, born 15 August 1990. The page in Famous charts casts the chart for noon, because the records those pages come from hold no birth time, and this example does the same and leaves the Moon out. Cast that way, the nine planets from the Sun to Pluto make a Grand Trine: Mercury, Mars and Saturn.

Mercury 19°31′ Virgo, Mars 21°28′ Taurus, Saturn 19°51′ Capricorn.

• Mercury trine to Mars1°57′ from exact, limit 6°
• Mars trine to Saturn1°37′ from exact, limit 6°
• Mercury trine to Saturn0°20′ from exact, limit 6°

All three planets are in earth signs.

These orbs are measured at noon. The Sun moves about a degree a day, and Mercury, Venus and Mars can move more, so a figure that includes one of them can shift by half a degree or more with the real hour of birth. With the Moon left out this is the chart of nine planets, and the figure is the same whatever the hour, so it is as firm as an example can be without a birth time.