Astrological Signs

Ancient Greek Star Signs

The Zodiac refers to a region of the sky visible around the Earth at eight degrees North or South of the sun's visible orbit (called the ecliptic). This is based on the position of the sun at the solstices and equinoxes. The twelve Zodiac signs correspond to twelve constellations that cross the ecliptic, at roughly even spaces, around the Zodiac. The Zodiac was observed by Babylonian astronomers, but Western astrology is mostly inherited from the Greeks (who inherited it from the Babylonians). The Zodiac is named for the constellations, as the name comes from a Greek phrase meaning the "cycle of the animals".

Birth Chart

In astrology, the most important and popular item of note is one's sun sign; this is the main constellation in the region of the zodiac said to "contain" the sun on the day of one's birth. The Zodiac begins at 0 degrees with Aries, based on the position of the sun during the vernal equinox. You can find your sun sign in the natal chart below:

symbol for aries
Aries (Ram): March 21–April 19
symbol of Taurus
Taurus (Bull): April 20–May 20
symbol for gemini
Gemini (Twins): May 21–June 20
symbol for cancer
Cancer (Crab): June 21–July 22
Leo (Lion): July 23–Aug. 22
Virgo (Virgin): Aug. 23–Sept. 22
Libra (Scales): Sept. 23–Oct. 22
Scorpio (Scorpion): Oct. 23–Nov. 21
Sagittarius (Archer): Nov. 22–Dec. 21
Capricorn (Goat): Dec. 22–Jan. 19
Aquarius (Water Bearer): Jan. 20–Feb. 18
Pisces (Fish): Feb. 19–March 20

There is sometimes credited a thirteenth sign, the constellation Ophiuchus, which also crosses the ecliptic. However, this does not evenly space around the orbit like the other twelve, so it is not considered part of the Zodiac.

Graeco-Roman Astronomers and the Signs of the Zodiac

In ancient Greece, the different planets and stars (the heavenly or celestial bodies) were related to different elements and energies. This is the basis for thinking that the position of the stars and planets at one's time of birth affects their personality traits. The thought went that the four elements were the product of different energies, and that the sum balance of those energies in a person affected their psyche. This is similar to the idea of the Four Humors postulated by the ancient physician Hippocrates, which attributed personality to the balance of fluids in the body. 

The full depth of determining one's astrological signs would take a long time explain. The different constellations are considered air signs, fire signs, water signs, or earth signs. These can be positive or negative, and they can be cardinal, fixed, or mutable. These sets of three and four signs are known as Triplicities and Quadruplicities.

Depending on the positions of each planet in the sky, relative to the constellations, these signs are dignified or in detriment. The planets might also be exaltation or in their fall. As well, different celestial bodies are considered the rulers of different constellations, which affects their qualities. The "rulers" are the Sun, Mercury, Venus, the Moon, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto.

It is all incredibly complicated. What astrologers believes those different elements to mean could fill an entire book (and it has, many times).

Modern Astrology

Modern astrologers employ their zodiacal knowledge to pseudo-scientifically predict the future or to analyze someone's psyche. This is most commonly shared via horoscopes or horoscopy (the "observation of time"). On top of horoscopes, books on astrology are very popular for prognosticating about emotional compatibility, finances, career success, etc. 

And, despite a decline in religiosity, astrology has remained popular in Western countries. It seems there is always a market for fortune-telling.

Changes Over Time

The relative position of the constellations has actually changed in the past millennia, due to a change in the Earth's rotation called the Precession of the Equinoxes. This change of the orbits is used to define the boundaries of different "ages" in which different signs are especially important. People attribute these big historical shifts with the course of major historical events.

The "Chinese Zodiac"

Although they're both called the Zodiac by westerners, there isn't much relationship between the Chinese Zodiac and the Graeco-Roman Zodiac. They are both 12-part cycles of different animals/figures said to affect one's personality. So, the word "Zodiac" was applied by Western writers who discovered the Chinese system of years as a sort of rough shorthand. But, this ignores the point that the Zodiac is a description of space, not a description of the constellations or their astrological significance.

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