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Hi Eon,

The short answer is "Constellations don't affect man." Most astrologers use the tropical zodiac, which begins at the vernal equinox, the point where the apparent path of the Sun crosses the celestial equator. That point is 0 degrees Aries. Each sign occupies 30 degrees of arc from that point on. The signs have the same names as the constellations of the zodiac, but, like I said, most astrologers don't plot the planets according to their positions in the constellations. Rather they plot them in accordance with the system mentioned above. The signs and constellations do not line up.

There are many good beginner's books on the market that explain this in detail.

If you're looking for some kind of physical cause and effect, many astrologers don't buy into that either, but some think it will be found someday.

Tom

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Just to take Tom's commnts a little further - The Sun is the major planet in Astrology - the apparant path of the Sun around Earth (the ecliptic) is seen against the background of the constellations of the Zodiac, therefore constellations which the Sun does not pass through are seen as having no relevance.

There are still Astrologers who use the Sidereal Zodiac, mainly Vedic Astrologers, but they two keep to the twelve Zodiac signs.

Declination North or South of the Celestial Equator is taken into account in Astrology but this is not particularly great - mainly between the Tropics of Cancer and Capricorn, though some planets do go 'out of bounds' to a relatively small extent. The 'action' therefore is really on or about the plane of the Celestial Equator