Astronomy for Astrologers
the horizon (starting, for astrological use in this book,
from the East point and moving in a counterclockwise
direction through the North point and on around, in the
same way that we are used to measuring the houses or
signs).
The Horizon System is built around a specific place or
event on earth, and all other objects—such as planets,
stars, cities, etc—are then expressed in terms of how
they were oriented to or appear from the perspective of
that place or event. The horizon system is most like the
standard road map in that it has a North-South-East-
West orientation. The North-South axis is identical to the
Celestial Meridian running from the North (geographic or
celestial) Pole, through the observer, and down to the
South Pole. The East-West circle is called the Prime
Vertical, and runs due East or West from the observer. It
does not follow the East-West geographic parallels of
latitude. The horizon system can be used anyplace on
earth.