Earth is the center and kept stationary in natal astrology with the Sun walking around it. The first house is always constant and falls between the point where the sun rises, which is on the eastern horizon, and the rising sign known as the Ascendant, which is on the west. So, when viewed from heaven, the directions of the hemispheres are reversed, with the left half of the circle being the eastern hemisphere, the right one being the western hemisphere, the top half being the southern hemisphere called the South Midheaven or Medium Coeli (MC), and the northern half being referred to as the northern hemisphere called the lowest heaven or Imum Coeli(IC).
With these hemispheres overlapping the twelve houses in the wheel of the horoscope, each hemisphere contains certain planets and expresses the characteristics peculiar to those occupied planets in the various houses.
Eastern hemisphere: Houses 10, 11, 12, 1, 2, and 3 comprise the Eastern hemisphere, lying on the western or left half of the pie or the wheel of the horoscope.
Western hemisphere: Houses 4, 5, 6, 7, 8, and 9 comprise the Western hemisphere, which lies on the eastern or right half of the horoscope wheel.
Northern hemisphere: Houses 1, 2, 3, 4, 5, and 6 comprise the Northern hemisphere, lying on the lower half of the horoscope circle.
Southern hemisphere: Houses 7, 8, 9, 10, 11, and 12 form the southern hemisphere of the horoscope circle, which occupies the top half of the wheel of the horoscope.