The word horoscope did not start out as the name of a newspaper column. In Greek, horoskopos meant the marker of the hour. The astrologers who first used it gave it to a single point in the chart, the degree of the zodiac rising over the eastern horizon at the moment of birth. That point changes faster than anything else in the sky. It could mark the hour more precisely than any planet could. It is still the place where every chart begins.
Lesson two showed you the horizontal line that runs across your wheel. It is the horizon of your birthplace. Whatever sat above it was in the visible sky and whatever sat below was on the far side of the Earth. That line has two ends. A second line runs from the highest part of the sky to the lowest and has two ends of its own. Those four ends are the angles of the chart. The houses in the next lessons are built on them.
Four points with names
The Ascendant is the left end of the horizon, the degree of the zodiac that was rising in the east when you were born. The sign on that point is your rising sign, the third of your big three. Across from it, at the right end, sits the Descendant. That is the degree that was setting in the west at the same moment.
The other line joins the Midheaven and its opposite. The Midheaven is the degree of the zodiac that was culminating, the one that had reached its highest point in the sky over your birthplace. Directly opposite lies the point that was beneath your feet on the other side of the Earth. Most charts label these two MC and IC, short for their Latin names, Medium Coeli and Imum Coeli. In English the IC rarely gets a name of its own beyond those two letters.
These are ancient in the full sense. Hellenistic astrologers were working with them more than two thousand years ago and called them the four pivots. The Ascendant was the one they named the horoskopos.
Why they depend on the time
The Earth turns once a day. In that time the horizon of any place sweeps through the whole zodiac. The Ascendant moves about one degree every four minutes. Twins born twenty minutes apart can already have their Ascendants five degrees apart. On average a new sign rises every two hours. Depending on the sign and the latitude, some rise in under an hour and others take close to three.
That is why the angles are the part of a chart that relies most on an exact birth time. It is also why they are the part that belongs to you most personally. If you do not know your time, lesson seventeen explains what can still be done.
A real chart shows one more thing straight away. The Midheaven does not always sit a quarter turn away from the Ascendant. At the latitude of London the gap between them runs from about fifty-five degrees to about a hundred and twenty-five, depending on the time of day. The cross formed by the four angles usually comes out tilted, with some quarters wider than others. That is where the houses of different sizes in lesson two come from.
What each angle tells you
The Ascendant is the way you step into life. It describes how you meet anything new and the impression you make before you have said a word. It is closely tied to the body, to posture and to the pace at which you move through a room. Everything else in the chart passes through it. The same Sun can come across very differently depending on the sign that was rising.
The Descendant faces the other person. It speaks about who draws you in and how you behave in relationships between equals, with partners in love and partners in work. Quite often it holds qualities you find hard to see in yourself and end up looking for in someone else.
The Midheaven is the most visible part of a life. It relates to vocation and to the place you hold in the world, to what people know you for from a distance. It does not always match the job you happen to have at a given moment. Usually it describes the direction you climb toward over the years.
The IC is the root. It speaks about home, about where you come from and about what holds you up in private. It is the part of the chart that shows least from outside and often weighs the most once the front door is closed.
Two axes
The four angles work in pairs. The horizon, from Ascendant to Descendant, is the axis between you and other people. The vertical line, from the IC up to the Midheaven, runs from the most private part of life to the most public. The whole chart is organized around that cross.
In Placidus, the house system this course uses, each angle opens a house. The Ascendant opens your house 1 and the IC opens your house 4. The Descendant opens your house 7 and the Midheaven opens your house 10.
Two ways to draw the houses
Placidus is not the only way to divide a chart. The oldest system on record is whole signs, the one Hellenistic astrologers used. In it the sign that was rising when you were born is your entire house 1, the next sign is your house 2 and so on around the wheel. Every house is one full sign and they are all the same size.
The Ascendant still falls in house 1. The Midheaven, though, does not always open house 10. At the latitude of New York or Madrid it lands in house 10 a little over half the time and in house 9 or 11 the rest. Further north, in London, it can even fall in house 8 or 12.
Placidus takes its name from Placidus de Titis, a seventeenth-century Italian monk who taught mathematics in Pavia. He did not invent it. In the twelfth century Abraham ibn Ezra already described it as the method of Ptolemy. It divides each quarter between two angles by time, so the four angles always open houses 1, 4, 7 and 10 and the houses come out in different sizes. Beyond the polar circles it stops working, because there some degrees of the zodiac never rise.
This site uses both, each where it fits. The course and the birth chart readings use Placidus, because it ties every house to the four angles of your exact birth time. The weekly transit articles by rising sign use whole signs, because an article written for everyone can only count the houses from the rising sign. Neither one is the true one. They are two ways of measuring and a planet can change house from one to the other.
Planets sitting on an angle
Take your wheel. Find the four angles and write down the sign on each one. The Ascendant is on the left and the Descendant on the right. The Midheaven sits near the top and the IC near the bottom, though almost never exactly vertical.
Then check whether any planet sits very close to one of them. The tradition gave special weight to planets right on an angle and in practice they tend to stand out. Mars on the Ascendant often shows in the body, in a quick stride and a readiness to argue. Venus close to the Descendant tends to bring a great deal of grace into partnerships. She usually draws people in with very little effort.
If you want to see it in motion, activate your birth chart in the AstroVisor 3D app, free on Google Play. You will see the wheel with your signs, your houses and the four angles exactly as they stood when you were born.
With the angles in place you have the frame of the houses. The next lesson walks through the first six, the ones that face inward.