TheMightyWings, 13 Zodiac signs(Compiled)

13 Zodiac signs ...

Source:- http://en.wikipedia.org/wiki/Zodiac ; http://www.bbc.co.uk/dna/h2g2/A32778615
Image source: http://cindyrockney.com/PHOTOS/stars/11_serpens_and_ophiuchus.gif (Ophiuchus 'the Serpent Bearer')

Are you sure that there are only 12 signs in the Zodiac? ... pen

Ophiuchus 'the Serpent Bearer' Image source: http://cindyrockney.com/PHOTOS/stars/11_serpens_and_ophiuchus.gif One particular set of constellations deserves a special mention - these are the twelve constellations of the zodiac. As the Earth moves around the Sun, the Sun appears to move around the celestial sphere, taking a full year to do one circuit. The path of the sun and the narrow band around it on the celestial sphere is known as the zodiac. Since the planets all orbit the sun in roughly the same plane, they will all appear to be in the zodiac as well.

The ancient Babylonians divided the zodiac into twelve constellations, which are known as the 'signs of the zodiac'. At any time, the sun will be between us and one of the signs; it is said to be 'in the sign'. Similarly, the planets move from sign to sign as they orbit the sun.

The Babylonians believed that the fate of humans was governed by the positions of the sun, moon and planets in the zodiac. Despite the lack of any evidence to support it, this belief appears to be still prevalent in modern society, and horoscopes based on the zodiacal signs are published in the popular culture newspapers and magazines.

When the IAU defined the boundaries of the constellations, this produced an oddity: the sun now passes through 13 constellations on its journey around the celestial sphere. The 13th 'sign of the zodiac' is Ophiuchus the Serpent Bearer, but this sign has not been incorporated into popular culture.

The inclusion of Ophiuchus 'the Serpent Bearer' - that the Sun passes through: 30 November to 18 December, makes 13 signs in the Zodiac.

The Science Bit

Due to the precession of the Earth, the dates for the Sun to be in the different zodiacal signs have changed over the two thousand years since they were worked out. For example, the Sun is in the sign Taurus from 15 May to 21 June whereas the incorrect dates of 21 April to 21 May are given in the popular magazines. Experiments show that either set of dates can be used for fortune telling with considerable accuracy.
Because the Earth travels around the Sun, the Sun appears to travel in a circle around the celestial globe, taking a full year to do one circuit. The path of the Sun against the background stars is known as the 'ecliptic'. Because the planets don't all go around the Sun in exactly the same plane, their apparent paths across the sky will not be exactly along the ecliptic, but they will always be close to it. If you plot the paths of the planets, you'll get a narrow band around the ecliptic, which is known as the zodiac: 'zodiac' means 'circle of animals', referring to the starry animal shapes encircling the Earth.

Redefining the Boundaries

When the IAU defined the boundaries of the constellations, this produced an oddity: the Sun now passes through 13 constellations on its journey around the celestial sphere. The 13th member of the zodiac is Ophiuchus 'the Serpent Bearer', but this sign has not been incorporated into popular culture, and doesn't have an astrological talisman like the other 12. The astrologers probably wouldn't want to recognise 13 zodiacal constellations anyway, as some people deem that an unlucky number.

Due to the precession of the Earth2, the dates for the Sun to be in the different zodiacal signs have changed over the 2,000 years since they were worked out. For example, the Sun is in the sign Taurus from 15 May to 21 June, whereas the incorrect dates of 21 April to 20 May are used by astrologers.

The 12 Popular Signs

Aries - dates used by astrologers: 21 March to 20 April
Taurus - dates used by astrologers: 21 April to 20 May
Gemini - dates used by astrologers: 21 May to 22 June
Cancer - dates used by astrologers: 23 June to 23 July
Leo - dates used by astrologers: 24 July to 23 August
Virgo - dates used by astrologers: 24 August to 23 September
Libra - dates used by astrologers: 24 September to 23 October
Scorpio - dates used by astrologers: 24 October to 22 November
Sagittarius - dates used by astrologers: 23 November to 21 December
Capricorn - dates used by astrologers: 22 December to 20 January
Aquarius - dates used by astrologers: 21 January to 19 February
Pisces - dates used by astrologers: 20 February to 20 March

The 13 Accurate Signs

The following dates depend upon whether the year is a 'leap' or not. We'll try and keep this simple by starting off with Aries, the same one western astrologers use:

Aries 'the Ram' - dates the Sun passes through: 19 April to 14 May
Taurus 'the Bull' - dates the Sun passes through: 14 May to 21 June
Gemini 'the Twins' - dates the Sun passes through: 21 June to 21 July
Cancer 'the Crab' - dates the Sun passes through: 21 July to 11 August
Leo 'the Lion' - dates the Sun passes through: 11 August to 17 September
Virgo 'the Maiden' - dates the Sun passes through: 17 September to 31 October
Libra 'the Scales' - dates the Sun passes through: 31 October to 23 November
Scorpius 'the Scorpion' - dates the Sun passes through: 23 November to 30 November
Ophiuchus 'the Serpent Bearer' - dates the Sun passes through: 30 November to 18 December
Sagittarius 'the Archer' - dates the Sun passes through: 18 December to 19 January
Capricornus 'the Sea Goat' - dates the Sun passes through: 19 January to 16 February
Aquarius 'the Water Carrier' - dates the Sun passes through: 16 February to 12 March
Pisces 'the Fish' - dates the Sun passes through: 12 March to 19 April

Experiments show that either set of dates can be used for fortune telling with equal accuracy. So, if you've never felt like a true Gemini, you now have another choice of horoscope to read!