30 Days Lesson Of Astrology

The Four Major Mathematical Points of the Zodiac

In Astronomy the Eastern Horizon is called the Ascendant. 180 degrees from it is the Western Horizon called as the Descendant. The intersecting point where the Ecliptic cuts the Celestial Meridien is called the Meridian Cusp (M.C.) and 180 degrees from it is called the Imum Coeli (I.C.).

The Computation of Houses

First the longitude of the Ascendant is calculated by using the following formula:

Tan L = Sin E / (Cos E * Cos w - Sin w * Tan A)

…where L is the Ascendant, E is the Right Ascension of East Point , w the Sun's maximum declination and A - the latitude of the place.

Once the Ascending degree is known, 180 degrees is subtracted to get the Descendant.

The MC is calculated by using the following formula:

Tan K = Tan R / cos w

…where is the longitude of the MC, R the Right Ascension of the Meridien Cusp and w the Sun's maximum declination.

180 degrees deducted from the MC is the longitude of the IC.

These 4 are the Four Houses of the Zodiac. Ascendant is the 1st House, IC the Fourth, Descendant the Seventh and MC, the tenth.

We have said that each sign of the Zodiac is 30 degrees each. If the Ascending Degree is Pisces, then the Ascendant is Pisces, the IC is Gemini, the Descendant is Virgo and the MC, Sagittarius.