Trine

What it means

The easy angle. Two bodies a third of the circle apart are read as working together without effort, which is also why a trine is easy to overlook.

The geometry of the trine

A trine divides the circle by three, and three trines draw an equilateral triangle. Signs a trine apart are four signs from each other and always belong to the same element: Aries, Leo and Sagittarius in fire; Taurus, Virgo and Capricorn in earth; Gemini, Libra and Aquarius in air; Cancer, Scorpio and Pisces in water. They differ in modality, one cardinal, one fixed and one mutable, so each corner of the triangle does the same thing in its own way. That shared element is the whole basis of the trine’s reputation for ease.

By sign count, the fifth and ninth houses stand a trine from the rising sign, and they carried two of the most favourable old house names, Good Fortune and God.

How the trine is read

The tradition reads a trine as flow: two planets whose natures support each other, so the things they stand for work together without friction. Modern writers add a caution that ease can turn into complacency, since nothing in a trine demands to be used. Between personal planets it is read as a natural gift. The Moon trine Venus is read as warmth and an easy way with people; Mercury trine Mars as quick, confident thinking and speech.

With a slow planet the trine is read as support that lasts. The Sun trine Jupiter is read as optimism and generosity, Venus trine Saturn as loyalty and affection that hold steady over years, and the Moon trine Neptune as sensitivity and imagination. Some trines cannot happen at all: Mercury and Venus never get far enough from the Sun, or from each other, to reach 120°.

Orb, applying and separating

This site counts a trine within 7°, or 9° with the Sun or the Moon, the same as the square, and uses 6° when two charts are compared. Like any aspect it is applying while the faster planet is still moving towards 120° and separating once it has passed. Because outer planets turn retrograde for months at a time, a slow transiting trine to a natal planet can come exact, drift apart and come exact again, up to three times.

Where you meet a trine

In a birth chart trines are drawn in the cool blue-green shared with sextiles. Three planets each a trine from the others, normally all in one element, make a grand trine, and a fourth planet opposite one corner turns it into a kite; both are described on the aspect patterns page. In synastry a trine between two people’s planets is read as instinctive understanding in that area of life, and on the transits page a trine from a moving planet is read as a stretch when that part of the chart is supported rather than tested.

Common confusions

A trine is not lucky. The tradition calls it soft because it asks for little, and a soft aspect can simply be left idle; many astrologers read a chart full of trines and short of squares as talented but unpressed. The out-of-sign trine is the other trap. 28° Aries and 2° Virgo are 124° apart, a trine by degree, but Aries is fire and Virgo earth, so the shared element that defines a trine is missing, and the aspect is read as weaker or more mixed.

A trine worked out

The Sun at 8° Sagittarius and Jupiter at 13° Aries are 125° apart, 5° past exact and within orb: a trine between two fire signs. Venus at 21° Cancer and Neptune at 29° Scorpio are 128° apart, both in water signs, yet 8° wide and outside the 7° allowed between planets, so no line is drawn. Sharing an element is not enough; the degrees decide. For a grand trine all three sides have to hold: planets at 5° Aries, 9° Leo and 4° Sagittarius stand 124°, 115° and 121° apart, each within orb, and the triangle closes.

The word, the triangle and Jupiter

Trine comes from the Latin trinus, threefold; Spanish and Portuguese keep the Greek word for a triangle, trígono. The three signs of one element were themselves called a trigon or triplicity, and the tradition gave each its own ruling planets, one of the dignities. Older authors gave the trine the nature of Jupiter: counted from Cancer and Leo, the signs of the Moon and the Sun, the signs Jupiter rules in the traditional scheme, Pisces and Sagittarius, stand a trine away.

Trines in the month and in the centuries

The Moon is trine the Sun twice a month, about ten days after the new Moon and about ten days before the next, on either side of the full Moon, and each time for about a day and a half. On a far longer scale, each meeting of Jupiter and Saturn falls roughly a trine further round the zodiac from the last. That is why their conjunctions stay in signs of one element for long runs before moving on to the next.