Any astrological report you may receive will refer to the AC (the Ascendant), the MC (Midheaven), and possibly the DC (Descendant) and the IC (Nadir, or Imum Coeli). These four points on the chart are called the angles, and they are in many ways as important as the locations of the planets in your chart.
The early astrologers considered the Ascendant and Descendant to be supremely important, because they mark the points in your chart where the sky (home of the gods) touches the earth (home of mankind) at the moment of your birth. Let’s take a look at these important points and discuss what they mean.
If the astro chart were a clock, the angles would be at noon, 3:00, 6:00, and 9:00.
The “9:00” angle, the Ascendant or AC, is the most important of the four. It’s the point in the zodiac which was rising over the eastern horizon at the moment you were born. It determines the ruling planet of your chart, and it indicates your public “self” — how people perceive you when they first meet you.
(This is also why knowing your birth time is important. Birth time determines the position of the AC, the rising sign, the ruling planet, and the locations of the houses in your birth chart.)
Going counterclockwise, we pass through houses 1, 2, and 3, which are about your sense of self and how the world relates to you. At the bottom of the chart, at “6:00,” we find the IC, the Imum Coeli (Latin for “bottom of the sky”), between houses 3 and 4.
The IC is the very root of who you are. It’s about your birth family, your upbringing, how you were nurtured as an infant, and by whom. Think of the IC as the roots of a huge tree — hidden from view, but the foundations of all that is displayed in the light.
Continuing through houses 4, 5, and 6, we move through the areas of your life involving creativity and productivity. This is things that make you happy — your own family, children, your creative impulses — as well as your daily work and your physical wellbeing. We are moving from the province of strictly “me” through “me and my immediate circle”, arriving at the 3:00 angle, the Descendant or DC.
The DC is the point in the zodiac that was disappearing below the western horizon at the moment you were born, the “sunset” of the chart. The DC and the Seventh house indicate long-term partnerships, both platonic (business relationships) and personal. Look to the chart near the DC for clues as to the kind of person who will attract you.
Traveling onward through houses 7, 8, and 9, we move through the area of relationships with others. Our world is expanding outside our own family and work relationships. Think philosophy, life-expanding travel and other experiences, spirituality, learning about the world.
At the “12:00” position, we find the MC (Medium Coeli) or Midheaven. This was the point at the top of the sky when you were born. I think of it as the canopy of that tree that is rooted in the IC — this is what people see most clearly. This is your reputation, your legacy, your accomplishments, your perception as a public figure. Planets near the MC will be important in suggesting information about your career and success in business.
Finally, we move through houses 10, 11, and 12 on the chart. Houses 10 and 11 are concerned with collective society, with friends, business colleagues, organizations to which you belong, and society as a whole. House 12 begins to turn back inward, toward introspective thinking and time away from larger society.
from The Legacy of the Divine Tarot