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Why the signs are assigned to their ruling planets 
One question I've heard a lot throughout my studies is, "why do the planets rule the signs they rule?"
This is an extremely important question to ask, and the answer comes down to the basic astronomy of our solar system.
This is an extremely important question to ask, and the answer comes down to the basic astronomy of our solar system.
Thousands of years ago during the Hellenistic era, the hayday of traditional astrology, there was a concept called the Thema Mundi.
The Thema Mundi is the birth chart of the universe, in which all the planets are in their domiciles.
The Thema Mundi is the birth chart of the universe, in which all the planets are in their domiciles.
The thema mundi is like a cheat sheet. Its layout helps you understand and remember the basic principles of astrology.
The thema mundi has a cancer rising w/ moon in the 1H. The rising and moon are the two most personal placements because they move through the signs so fast
The thema mundi has a cancer rising w/ moon in the 1H. The rising and moon are the two most personal placements because they move through the signs so fast
But why was the sign cancer given to the moon?
The moon and sun, the two luminaries, are given to cancer and leo, the hottest seasons of the year with the most sunlight (in the western hemisphere at least).
The moon and sun, the two luminaries, are given to cancer and leo, the hottest seasons of the year with the most sunlight (in the western hemisphere at least).
Mercury, who can never be more than one sign away from the sun because of its orbit, gets the signs on either side of the luminaries, gemini and virgo.
Venus, who is always within 2 signs of the sun, gets the next two signs away, taurus and libra.
Venus, who is always within 2 signs of the sun, gets the next two signs away, taurus and libra.
The rest's positions are relative to their distance from the sun
mars gets aries/scorpio, jupiter gets pisces/sagittarius, and saturn, as the farthest, coldest planet gets capricorn/aquarius, the two signs farthest from the luminaries whose seasons occur in the dead of winter.
mars gets aries/scorpio, jupiter gets pisces/sagittarius, and saturn, as the farthest, coldest planet gets capricorn/aquarius, the two signs farthest from the luminaries whose seasons occur in the dead of winter.
The positions of the planets in this configuration also correlate to the aspects each planet makes to the luminaries in this arrangement.
Saturn (capricorn and aquarius) is opposite (180°) the luminaries (cancer and leo). Saturn is considered the greater malefic, and the opposition is the most difficult aspect.
Jupiter (pisces and sagittarius) is trine to (120°) the luminaries. Jupiter is considered the greater benefic, and the trine is considered the most desirable aspect
Mars (scorpio and aries) is square to (90°) the luminaries. Mars is the lesser malefic, and the square is considered the less challenging of the two hard aspects.
Venus (taurus and libra) is sextile to (60°) the luminaries. Venus is the lesser benefic, and the sextile is considered the less beneficial of the two soft aspects.
