Trine
The trine is, in astrology, an aspect formed between two planets separated by 120 degrees. It belongs to the five major aspects and is classically considered the most harmonious, signaling a fluid circulation of energy between the planets involved.
Origin and etymology
The word comes from the Greek trigonos, meaning triangular, the trine corresponding to one third of the zodiacal circle (360 / 3 = 120). The aspect was codified by Claudius Ptolemy in the Tetrabiblos in the 2nd century. The medieval Arab and then Latin tradition classifies the trine among the major benefic aspects. The concept is linked to that of elemental triplicity: the three fire signs (Aries, Leo, Sagittarius), the three earth signs (Taurus, Virgo, Capricorn), and so on, form equilateral triangles on the zodiac. Johannes Kepler in Harmonices Mundi (1619) confirmed the centrality of the trine in the hierarchy of aspects.
Evolution and tradition
Traditional astrology sees the trine as a granted grace: a talent that expresses itself effortlessly, favorable terrain. This reading was nuanced in the 20th century. Liz Greene emphasized that trines can also describe gifts that remain inactive for lack of stimulating tension. A grand trine brings together three planets at 120 degrees from each other, in signs of the same element, forming a perfect equilateral triangle on the zodiac. This configuration is traditionally very favorable, but can induce a certain passivity. The orb of a trine varies by school, generally from 6 to 10 degrees.
Practical use
A natal trine between two planets signals a natural cooperation between two psychic functions of the same elemental nature. A Mars-Jupiter trine, for example, favors confident and expansive action. In predictive astrology, transits forming a trine to a natal planet open periods favorable to the domain concerned. On Tarotoui, trines are automatically identified in natal chart and transit calculations. Many modern astrologers caution against relying solely on trines, which describe potential but do not mobilize it on their own.
Going further
Considering the trine as solely positive is an old simplification. A chart dominated by trines can produce a comfortable life with no evolutionary dynamic. Difficult aspects (squares and oppositions) provide the friction needed for maturation. Note that trines always link planets in signs of the same element, which amplifies their coherence.