The birth chart answers one question: who you are. It does not answer the other one, the one that almost always brings people in: why now.
Transits answer that, and the mechanism is simpler than it looks.
The idea
Your birth chart is a still photograph. The degree your Sun stood at on the day you were born stayed there for good; so did your Moon, your ascendant and everything else.
But the real sky kept moving. Today Saturn sits at some degree of the zodiac, and Jupiter at another. When one of today's planets passes right over a point of your fixed chart, it is said to transit it. That meeting is what marks a period.
In other words: the sky is not doing something to you. A slow-moving body is coinciding, for months, with a point that means something specific in you.
The hierarchy: the slowest one rules
Not every transit weighs the same, and the rule for ranking them is speed.
The Moon crosses the whole zodiac in 27 days: it passes over each point of your chart once a month and lasts hours. It is the weather of the day, and explains nothing important.
The Sun, Mercury and Venus pass once a year and last days. Mars takes two years and stays for weeks. Jupiter takes twelve years; Saturn, twenty-nine; Uranus, eighty-four; Neptune, one hundred and sixty-five; Pluto, two hundred and forty-eight.
Hence the practical rule: what changes a life is marked by the slow ones. A Pluto transit over your Sun happens once, if it happens at all. A Moon transit happens every month.
Why they feel long: the three passes
A slow planet does not cross your point once and leave. It advances, stops, moves back for some months and returns. So it usually crosses the same degree three times, spread over a year or a year and a half.
There is usually an order to those three passes: the first raises the matter, the second forces you to look at it when it seemed closed, and the third settles it. The Saturn return is the best known example of this rhythm.
Where it lands: the house
Knowing Saturn is transiting you does not say much yet. What makes it concrete is which house it is crossing and which point of yours it touches.
The same Saturn transit in the fourth house speaks of family and where you live; in the tenth, of work and public life. Same planet, same date, two different lives.
What can and cannot be said
A transit does not say what will happen to you. It says which matter comes to the front and for how long. That distinction is the difference between a useful reading and a guess.
In practice, what can be known precisely are the dates: when it starts, when it is exact, how many passes it makes and when it ends. That is arithmetic, and it computes the same for everyone. How each piece is read is in the birth chart guide.
The short version
- The birth chart is fixed; the sky moves on. The crossing of the two is a transit.
- The slower the planet, the heavier and the longer.
- Slow planets cross the same degree about three times, over a year or a year and a half.
- The house it happens in says what the matter is about.
- The dates are calculable; the concrete outcome is not.
And yours — when does it actually land?
Your Year Ahead gives you the dates: the exact months the slow planets touch your chart over the next twelve, and what each one tends to move. Not the year in general — yours.
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