Astronomy for Astrologers
From the Sky to the Chart Form: Part 1
Our astrological 360° chart form (open style chart
wheel), represents the plane of the zodiac along which
our Earth moves in the course of a year. In addition, the
fact that almost all of the planets move in planes that
are almost (but not quite) identical or coincident with our
ecliptic, gives the zodiac plane even greater importance
than it would otherwise have. In fact, most astrologers
use only the zodiac longitude of a planet's position on
the plane of the zodiac and ignore the latitude—the
elevation of a planet either above or below the ecliptic
plane.
Here you can see the "band of the zodiac."