Sextile aspect in astrology
By Ines Vasquez
A sextile is a 60-degree angle between two planets in a birth chart or in transit. Astrologers read it as an easy, cooperative contact between the two — but one that stays dormant unless it is deliberately used. Unlike the trine, which is held to operate whether or not you notice it, the sextile is traditionally described as an opportunity that has to be taken up.
What does a sextile mean in astrology?
Sixty degrees of separation, one-sixth of the circle, and in interpretation a contact of ease and compatibility between the two planets involved. The classification is ancient: sextile is one of the five Ptolemaic aspects — conjunction, sextile, square, trine, opposition — set out by Claudius Ptolemy in the Tetrabiblos in the second century, and it has held that place in Western astrology ever since.
Ptolemy and the Hellenistic astrologers before him grouped sextile with trine as the two benefic or harmonious configurations, opposed to square and opposition. Where later astrologers began to differ from him is in force. Modern practice, from roughly the twentieth century onwards, treats the sextile as weaker than the trine and, more importantly, as conditional: available rather than automatic. The trine is read as talent that arrives unasked. The sextile is read as an aptitude you have to pick up and use, and which lies flat if you do not.
Why is 60 degrees considered harmonious?
Because of the signs it falls between. A sextile normally connects signs of compatible element — fire with air, or earth with water. Aries to Gemini, Taurus to Cancer, Leo to Libra, Virgo to Scorpio. Fire and air are both classed as masculine or diurnal in the traditional scheme; earth and water as feminine or nocturnal. Signs of the same category were held to see each other easily.
The geometric reasoning is older than the elemental one. Sixty degrees is the angle of the hexagon and one-sixth of the zodiac, and the Pythagorean strand in Hellenistic astrology valued aspects according to the simplicity of their arithmetic ratio to the whole circle. Simple division, easy relationship. The opposition divides the circle by two and was read as the hardest; the trine by three; the square by four; the sextile by six. By that logic the sextile is harmonious but attenuated, further along the sequence and correspondingly milder.
Ptolemy himself gives the arrangement of signs as the basis and the arithmetic as the justification. Both survive in modern textbooks, usually with the elemental explanation given first.
How is a sextile different from a trine?
Strength and automaticity, and the distinction is genuinely useful rather than a piece of jargon.
| Trine | Sextile | |
|---|---|---|
| Angle | 120 degrees | 60 degrees |
| Signs connected | Same element | Compatible element |
| Traditional classification | Benefic, the most harmonious | Benefic, milder |
| Usual orb | 6 to 8 degrees | 3 to 4 degrees |
| Modern reading | Operates without effort | Requires initiation |
The received modern formulation — that a trine gives and a sextile offers — is twentieth century in its emphasis, though the relative weakness of the sextile is much older. Vettius Valens, a practising astrologer of the second century, and later medieval authors including Abu Ma'shar in the ninth century, treated the sextile as a valid but less powerful testimony than the trine when weighing the strength of a configuration. What the twentieth century added was the psychological gloss: that the difference is not merely one of degree but of kind, and that the sextile's weakness is really a description of its needing your participation.
Whether that gloss is a discovery or a rationalisation is arguable. It is certainly not in Ptolemy. It is, however, the reading almost every contemporary astrologer works with, and it gives the sextile something the trine lacks, which is a use for conscious attention.
What orb does a sextile get?
Most modern astrologers allow 3 to 4 degrees. Some go to 6. Traditional astrology did not measure orbs from the aspect at all — it assigned each planet its own orb, so a sextile involving the Sun, with an orb of 17 degrees in William Lilly's Christian Astrology of 1647, was wider than one involving Mercury.
The narrower modern figure follows from the sextile being counted a weaker aspect: weaker aspects are given less room to operate. A sextile at 7 degrees from exact is usually treated as present but faint, and many astrologers would not interpret it at all except in a chart with very little else going on. An aspect that is tightening — where the faster planet is still approaching exactness — is traditionally read as stronger and more forward-moving than one already separating.
What does a sextile mean in a transit?
Applied to transits, the same conditional reading: a window, open for as long as the angle holds, in which something the two planets signify can be started with less friction than usual.
Transiting sextiles are short. The Moon makes one to every natal planet roughly every 28 days and it lasts a matter of hours. A Mars sextile lasts a day or two. An outer-planet sextile — Saturn, Uranus, Neptune, Pluto to a natal point — can hold for weeks and recur two or three times if the transiting planet stations retrograde within range.
Astrologers generally hold that the shorter the transit, the more it describes mood and the less it describes circumstance, so a Moon sextile is read as emotional weather rather than event. The longer outer-planet sextiles are where the conditionality bites hardest. Something is available for months and, if nothing is done, closes without incident and without any sense of loss. Nothing has gone wrong. Nothing happened at all. This is the most commonly reported frustration with sextiles among practising astrologers, and it is the reason the aspect is often described as the one that gets wasted.
Which planets sextile each other most often?
Mercury and Venus never sextile the Sun. Mercury never appears more than 28 degrees from the Sun, and Venus never more than about 47, which is a fact of their orbits rather than a doctrine. So neither Mercury nor Venus can ever form a sextile to the Sun. Venus at its furthest still falls some thirteen degrees short of the angle, which is wider than any orb in use.
Mercury and Venus can sextile each other, but only when both are near their opposite extremes of elongation, which is uncommon. The practical consequence is that a chart can show Mercury or Venus sextile almost anything except the Sun.
The slower pairs behave the opposite way. Neptune and Pluto held a sextile, within orb, for most of the twentieth century — from around the 1940s to the 2030s, an artefact of Pluto's eccentric orbit briefly bringing its speed into a near-resonance with Neptune's. Every person born in that span has it natally, which means it carries no individual information. Generational aspects of this kind are read, if at all, as describing a cohort rather than a person, and most astrologers only give them weight when one of them contacts a personal planet or an angle in the chart.
Is a sextile always a good thing?
Not necessarily, and the framing of aspects as good or bad is itself contested.
The traditional position is straightforward: sextile is benefic, and the planets involved express themselves comfortably. But traditional astrology also held that the nature of the planets matters more than the angle between them. A sextile between Mars and Saturn is still a contact between the two classical malefics; the geometry makes their cooperation smooth, which is not the same as making the result pleasant. Lilly and his sources weighed planetary nature, dignity and house placement alongside the aspect, and would not have read a sextile as good news in isolation.
The modern psychological tradition, which comes largely out of Dane Rudhyar in the mid-twentieth century and after him the humanistic and evolutionary schools, dropped the benefic and malefic labels almost entirely in favour of reading every aspect as a kind of relationship. On that view a sextile is neither good nor bad, only easy, and ease has its own costs: an aptitude that works without resistance is one you may never examine, and a facility can become a default. The hard aspects get the credit for producing character precisely because they insist on being dealt with.
Working astrologers are split on it, and have been for a century. Traditional revivalists since the 1990s have restored benefic and malefic as working categories; most mainstream modern practice has not. Where it matters for the sextile specifically, the disagreement is narrow — both camps agree the contact is cooperative, and differ on whether cooperative means beneficial.