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What moon phase were you born under?
The Moon was somewhere in its own cycle when you were born, and that is a separate placement from its sign. Enter a birth date and this works out which of the eight stages it was, from the angle between the Sun and the Moon in your chart.
The eight phases
The cycle runs from one new Moon to the next, about twenty nine and a half days, and is divided into eight stages of 45 degrees each. The discs below are drawn at the middle of each stage.
New Moon
0° to 45° from the Sun
The beginning of the cycle, and read as somebody who acts before the picture is complete. The tradition describes this as instinctive rather than considered: a New Moon birth is said to move on impulse and conviction, and to find out what a thing was by having already begun it. The strength is that starting is genuinely easy, which most people cannot say. The cost is a certain blindness to how a situation looks from outside it, since there was no light on the situation when it began.
In the sky: The Moon sat with the Sun and rose and set with it, lost in the glare. There was no Moon in the night sky at all.
Crescent Moon
45° to 90° from the Sun
The stage where the impulse of the New Moon meets the first resistance. Read as somebody who has to work against inherited expectation to get anything moving, and who feels that resistance as personal even when it is not aimed at them. The tradition frames this as the struggle to leave the past behind, and treats the effort itself as the point: a Crescent birth is said to build the thing rather than inherit it. What that produces is unusual persistence, and a tendency to assume any easy path must be the wrong one.
In the sky: A thin lit edge low in the west just after sunset, visible for a short while and then gone.
First Quarter Moon
90° to 135° from the Sun
The first of the two crisis points in the cycle, and the one that plays out in action rather than in understanding. Read as somebody who arrives at the moment where a decision cannot be deferred and makes it, frequently at a cost they have already accepted. The tradition calls this a crisis in action and does not treat it as a misfortune: it is the stage where a structure gets built, and building one usually means clearing the ground. The associated difficulty is a low tolerance for anybody still deliberating.
In the sky: Exactly half lit, high in the sky at sunset, setting around midnight.
Gibbous Moon
135° to 180° from the Sun
The stage just before completion, which the tradition treats as the analytical one. Read as somebody who examines what has been built and finds the part that is not right yet, and who is genuinely useful for exactly that reason. A Gibbous birth is described as questioning rather than doubting: the questions are aimed at making the thing work, not at abandoning it. The corresponding difficulty is obvious and the tradition states it plainly, which is that nothing is ever declared finished and the person is often hardest on their own work.
In the sky: Most of the disc lit but not all, rising in the evening and clearly short of full.
Full Moon
180° to 225° from the Sun
The Sun and Moon facing each other across the chart, which the tradition reads as the moment everything becomes visible. A Full Moon birth is described as objective in a way the New Moon is not: the situation can be seen from outside because there is light on all of it. That clarity is said to arrive through relationship rather than alone, which is why this phase is so consistently tied to other people in the older writing. The difficulty is the same fact from the other side, that an opposition is still a tension, and awareness of both positions does not resolve it.
In the sky: The Moon opposite the Sun, rising as the Sun set, lit completely and visible all night.
Disseminating Moon
225° to 270° from the Sun
The first stage after fullness, and the one the tradition associates with teaching in the broadest sense. Read as somebody who takes what has been understood and gives it away, whether that looks like teaching, writing, arguing a case or simply being the person who explains things. The reading is not that they know more than other people, but that they cannot leave a thing known and unshared. The stated difficulty is a dependence on being heard, since a conviction that nobody receives feels to this phase like a wasted one.
In the sky: Past full and visibly declining, rising later each night, still bright.
Last Quarter Moon
270° to 315° from the Sun
The second crisis point, and the tradition is careful that it is a different kind from the first. Where the First Quarter breaks something in the world, this one breaks something in the person: it is described as a crisis in consciousness, where the belief a thing was built on stops being convincing. Read as somebody who reaches conclusions well ahead of being able to act on them, and who can appear to abandon a position abruptly when in fact the position has been quietly eroding for a long time. The strength is genuine independence of thought.
In the sky: Half lit again, the other half this time, rising near midnight and highest at dawn.
Balsamic Moon
315° to 360° from the Sun
The end of the cycle, and read as the seed rather than the ending. The tradition treats this phase as concerned with closure: a Balsamic birth is described as good at endings, at knowing when something is genuinely over, and at extracting what mattered from it before letting the rest go. There is a persistent theme of separateness in the older writing, which is worth naming rather than dressing up, though it is described as a distance from the present moment rather than from people. The strength is a sense of what will still matter later.
In the sky: A bare sliver rising just before dawn, the last of the Moon before it disappears.
How this was worked out
Your birth date, time and place are turned into a chart, and the phase is the angle between the Sun’s position and the Moon’s in that chart. Nothing is looked up in a table, so the answer is as exact as the birth details given.
The eight stage scheme is Dane Rudhyar’s, set out in the 1960s. He treated the lunation cycle as one process with eight points in it rather than eight separate omens, which is why several of the readings above only make sense against the one before them.
Questions about moon phases
Including the one about other sites giving a different answer.
It is the angle between the Sun and the Moon at the moment you were born, divided into eight named stages of one lunar cycle. It is not the same as your moon sign: the sign says which part of the zodiac the Moon was in, and the phase says where the Moon was in its own cycle relative to the Sun.
Rarely. The Moon pulls away from the Sun by about 12 degrees a day and each of the eight bands is 45 degrees wide, so a band lasts roughly three and a half days. A missing time only changes the answer if you were born within a few hours of one band becoming the next.
Because there are two ways to divide the cycle into eight and they disagree by 22.5 degrees. Astronomy centres each name on its band, so a new Moon runs from 337.5 degrees through 0 to 22.5. Astrology, following Dane Rudhyar, starts each name at its band, so a new Moon runs from 0 to 45. This page uses the astrological division, which is why four of the names here, Crescent, Gibbous, Disseminating and Balsamic, do not appear on an astronomy site at all.
Because the percentage is the real astronomical figure and the name is the astrological band. A Balsamic Moon is the last eighth of the cycle, when almost nothing is lit, so a low percentage is what that name should show. The two numbers are measuring different things on purpose.