A map or any other projection of a three dimensional reality onto a surface, can only be an approximation. To a certain extent that reality is distorted, especially if it is spherical. We, who are used to looking at charts of the heavens, should be particularly aware of this and make amends by occasionally refreshing ourselves with a view of celestial phenomena on a clear night.
Have you ever asked yourself how you view the celestial sphere? For if you do, you will realize that you are always in its centre and that the only possible way to absorb it all is to let your eyes wander from right to left and above to below. Your field of vision is roughly able to take in at least one half of the celestial sphere, that which is behind you, you fill in with your imagination.
We are used to speaking of the angles of a chart. The Ascendant and the Descendant where planets rise and set or the Medium Coeli where planets reach their culmination or the Imum Coeli where they reach their nadir. But these words are not just terminology, they also reflect an accurate picture of celestial phenomena. So accurate that it is helpful to consider the visual reality. I would like to present a few two-dimensional images to help you in finding this visual reality. It will be up to you, dear reader, to go outside and experience the real thing!
This first image shows the rising of a celestial body in the east. This appears as a straight line at a relatively steep angle to the horizon. It is actually the bottom of a circle that extends from the east rises to the south and sets again in the west. This angle will vary depending on the latitude you are at. We will see shortly what a difference this can make.
This second image shows the celestial object moving to its culmination.
The third image shows the descension of the celestial object.
This image shows the movement of the celestial object towards its nadir. Notice that the circle appears to dip down just as in the south the movement appears to arc upward.
This last illustration would be how the movement of the celestial body would appear if you were standing on the north pole. The object would move in a circle around you parallel to the horizon. Those who live in the very far north have this experience with the Sun in high summer. The Sun moves in a circle around the horizon, without dipping below it.
If one keeps the appearance of these movements in mind then it becomes clear why the angles are so important in astrology and how the character of each is already shown at this very basic level.
Although out of print, “Astronomy and the Imagination” by Norman Davidson is a must for any astrologer who also wants to understand the astronomical phenomena! He describes ‘star trails’ in his text, which are the basis for the illustrations above.
Altair Astrology 