The astrological birth chart is a map of the sky, as seen from the earth. Your birth chart is an “energy map” showing the energies of that all-important moment in time— the moment you took your first breath.
An astrological birth chart is like a highly sophisticated clock.
The “numbers” on the clock would be the signs of the Zodiac. The planets are the hands of the clock that tell you what time it was when you were born. Was it Ram time (Aries)? Crab time (Cancer)? Balance time (Libra)? Or some other time?
If astrology is like learning a language, the planets are the verbs. The signs are adverbs. The signs modify the expression of the planets. Venus shows how you love. Venus in Cancer “loves” “nurturingly.” The signs are like the numbers on the clock. They are like a stained glass window that the light of the planets filters through.
Each of these clock hands, the planets, moves at a different rate. The Moon takes only 2.5 days to get through one sign, one hour of the clock.
Some go fast— for example, the Moon moves through one sign in 2.5 days and circles the chart every 27 days. Others move much more slowly— for example, Pluto can take up to 2 decades to get through one sign, and takes 250 years to circle all 12 signs.
If shown on the chart, the Earth would be in the middle.
Here’s the part that can be tough to grasp: You are living on a planet that rotates on its axis 360 degrees each day. Each day you can watch the Sun cross the sky. Likewise, in the chart, the planets rise and set, the sky appears to be moving around us. In our clock example, the “second hand” would be the face of the clock itself!
This is kind of hard to get at first. Astrology is geocentric— that means earth (us) in the middle. And from our perspective, the entire sky, the entire Zodiac, the Sun, Moon, and all the planets move across the sky, day after day.
To get a sense of this, run 12 charts for the same day. Start at midnight, then 2 a.m., then 4 a.m., then 6 a.m., and so on until you get to 10 p.m. (or you can just download this pdf file)
Flip the pages on your charts, and you’ll see how the Sun and planets move across the sky, but they do not change signs. Watch the sign on the ascendant and other house cusps shift roughly one sign every two hours.
You’ll see the Moon moving roughly one degree (the bold number) every two hours. The Sun, Venus and Mercury move roughly one degree per day, and other planets move more slowly.
See? If we’re the frame of reference, the sky is moving around us. And this is how the “chart of the moment” changes over time.
Using our clock example:
Now it is not only important that the big hand is pointing to 3 (Libra: preoccupation with fairness)— is it pointing up toward 3 (10th house- preoccupation with fairness in working life) or down toward 3 (4th house- preoccupation with fairness in the personal life)? Or some other house? That too is significant.
This is why it’s ideal to have an accurate birth time— the rising sign, or zodiac sign coming over the eastern horizon, changes every two hours. Throughout the day, planets move through the various houses.
There is still much good information to be found without the time of birth, so don’t despair if you don’t know it. You can see from the example charts that even though the planets move through all the houses in 24 hours, they move through the signs much more slowly. The Sun moves at the rate of one degree per day, so even without a birth time, it is still possible to pinpoint the location in the Zodiac of the Sun and the planets with accuracy. The Moon is trickier, since she moves at the rate of 12 degrees per day.
Ready to see your chart? How to get your chart online.