Zodiac Constellations

Zodiac comes from the Greek word zodiakos, " circle of small animals ". This name comes from the fact that all the constellations of the Zodiac (except the Libra, formerly left the Scorpio) represent living beings.
The general public heard about signs of the zodiac in an astrological context.
The zodiac is the name of the zone in heavens around the ecliptic where are observed the movements of the Sun as well as the planets. The trajectory of the Sun on the sky is the ecliptic.
We hold as conventional limit of the zodiac a band of eight degrees of bow on both sides of the ecliptic.
The zodiac is traditionally divided into twelve constellations corresponding to twelve signs.
In fact, the ecliptic crosses thirteen constellations in the sky, but the one of them, Ophiuchus (or Secretary bird), is not a part of the traditional Zodiac.

The present constellations in the zodiac are: The Aries, the Taurus, the Gemini, the Cancer, the Lion, the Virgo, the Libra, the Scorpio, Ophiuchus (or Secretary bird), the Sagittarius, the Capricorn, the Aquarius and Fishes.

Image: by agreement the names of the stars of a constellation are prefixed by a Greek letter followed by the first 3 letters of the constellation, the example: α  Ori, β Ori,... (Greek letters: α β γ δ ε ζ η θ ι κ λ μ ν ξ ο π ρ ς σ τ υ φ χ ψ ω).

The Aries indicates a constellation of the zodiac.
This constellation is crossed by the Sun from April 19th till May 13th.
In the order of the zodiac, the constellation is situated between Fishes on the West and Taurus in the East.
The Aries also indicates a sign of the zodiac corresponding to the sector of 30° of the ecliptic crossed by the Sun from March 21st till April 19th.
It is in this direction that it serves to the global location of the movement, still used in astrology. The constellation is not situated on adaptations very remarkable.

It finds a way from its circle of acquaintances: in the South of Perseus and Andromeda, and on the West the bull. It finds a way by its two main stars, α and β of the Aries, which point at nothing very evident (if it is Capella at rather big distance). Under the constellation of the Triangle, the constellation of the Aries will be easily locatable.
It is a constellation formed by stars of average brilliancy. Hamal, Sheratan and Mesarthim is the most brilliant.
Hamal is a giant whereas Mesarthim is a magnificent double star.

The Taurus indicates a constellation of the zodiac.
This constellation is crossed by the Sun from May 14th till June 19th.
In the order of the zodiac, the constellation is situated between the Aries on the West and the Gemini in the East.
The Taurus also indicates a sign of the zodiac corresponding to the sector of 30 ° of the ecliptic crossed by the Sun from April 20th till May 20th.

It is in this direction that it serves to the global location of the movement, still used in astrology.
In the Greek mythology, the Taurus would correspond either to the bovine shape used by Zeus to appoint the kidnapping of Europe, or to the white bull sent by Poseidon to Minos.

The direction of the Gemini will be indicated by the stars Rigel and Betelgeuse of the constellation of Orion. Indeed, if we draw an imaginary line between these two stars and if we pursue this line towards the North is, we shall reach then easily the Gemini, the very vast constellation in the form of rectangle.
Both more brilliant stud with the constellation is Pollux on the head of the Gemini of left (β Gem of magnitude 1,18 to 33,72 AL) and Beaver on the head of the Gemini of right (α Gem of magnitude 1,60 to 51,55 AL).
This last one is in fact a system of three stars whereas Pollux is a giant.
We also find in the Gemini, a beautiful opened heap. Messier 35.

Other stars of the constellation of Gemini are Wasat on the stomach of the Gemini of left (δ Gem of magnitude 3,52 to 58,82 AL), Mekbuda on the left knee of the Gemini of left (ζ Gem of magnitude 4,03 to 1169,03 AL), Alhena on the left foot of the Gemini of left (γ Gem of magnitude 1,95 to 104,81 AL), Propus on the left heel of the Gemini of right (π Gem of magnitude 3,33 to 349,21 AL) Tejat under the dress of the Gemini of right (μ Gem of magnitude 2,89 to 231,81 AL), Mebsuta on the dress of the Gemini of right (ε Gem of magnitude 3,08 to 903,49 AL).

The Crab, constellation of the Cancer is situated not far from the Gemini, shines the small constellation of the Cancer. It is formed by six stars.
These stars are of weak brilliancy. We find in this constellation a magnificent opened heap Messier 67.
The main stars of this constellation are Acubens on the right crowbar of the Cancer (α Can of magnitude 34,28 to 173,58 AL) and β Can on the right leg of magnitude 3,55 to 290,44 AL.

Other stars of the constellation are Asellus Australis on the right eye (δ Can of magnitude 3,96 to 136,07 AL), Asellus Borealis on the left eye (γ Can of magnitude 4,68 to 158,48 AL), on the left crowbar of the Cancer there is (ι Can of magnitude 4,05 to 298,14 AL), on the left leg turns out (χ Can of magnitude 5,15 to 59,12 AL).

The constellation of the Lion becomes identified thanks to a group of stars forming a characteristic drawing of sickle. We can easily observe this constellation in our hemisphere in spring. The most brilliant star of the Lion is Regulus (α Leo). it is situated in 68 light years of the Earth.
This constellation is crossed by the Sun from August 10th till September 16th. In the order of the zodiac, the constellation is situated between weakly brilliant Cancer on the West and the Virgo in the East.

This constellation contains several brilliant stars, such Regulus (α Leonis), the heart of the Lion, and Denebola (β Leonis), its tail.
The Lion also indicates a sign of the zodiac corresponding to the sector of 30° of the ecliptic crossed by the Sun from July 24th till August 23rd. It is in this direction that it serves to the global location of the movement, still used in astrology. 

The constellation of the Virgo is easily observable of our north hemisphere and serves as mark for the identification of the other constellations.
The Virgo contains a large number of distant galaxies among which some are visible in a telescope even average. This constellation is crossed by the Sun from September 16th till October 30th.
In the order of the zodiac, the constellation is situated between the Lion on the West and the Libra in the East.

It is an immense constellation (the second of the sky, after the Hydra) and extremely former.
The Virgo also indicates a sign of the zodiac corresponding to the sector of 30 ° of the ecliptic crossed by the Sun from August 24th till September 22nd.

This constellation is crossed by the Sun from October 31st till November 22nd.
In the order of the zodiac, the constellation is situated between the Virgo on the West and the Scorpio in the East.
It is the modest constellation which contains no star of first magnitude. It was formerly considered as the crowbars of the scorpion (its stars pull their name), and in the classic mythology, it was the balance of Astree, the virgin goddess of the Justice.

The goddess herself being represented by a nearby constellation, the Virgo.
As the name of the main stars of this constellation gives evidence of it, the Libra was originally (to Greek in particular) considered the crowbars of the constellation of the Scorpio.
We think that it is about Roman which introduced this constellation. It appears in the Julian Calendar in 46 BC.

This constellation is crossed by the Sun from November 23rd till November 29th. In the order of the zodiac, the constellation is situated between the Libra on the West and the Sagittarius in the East.
It is in the southern hemisphere, very widely under the ecliptic. Originally, the constellation also included the Libra. This last one was separated from the Scorpio to complete in twelve the number of the zodiacal constellations.

The Scorpio is the object of several legends according to the Greek mythology: it would be about the scorpion sent by Gaia (or Hera) to kill the hunter Orion.
So it is opposite to the constellation Orion, getting up in summer when Orion goes to bed.
Other versions suggest that Apollo sent the scorpion by jealousy to the attention which Orion carried to Artemis.

The Sagittarius (this term means " the Archer ") indicate a constellation of the zodiac.
This constellation is crossed by the Sun from December 18th till January 18th. In the order of the zodiac, the constellation is situated between the Scorpio on the West and the Capricorn in the East.
We also call it Arcifere (that is " the carrier of bow "). In the Greek mythology, the Sagittarius would represent the centaur Pholus, although certain sources associate it rather with Crotos or even with Chiron (itself associated with the constellation of the Centaur); it would be aiming at the Scorpio with its bow.

When the Scorpio is visible, the Sagittarius finds a way easily, by its shape.
It is situated in the axis of two " eyes of the cat " of the tail of the Scorpio.
The constellation is easily recognizable by an asterism in shape of teapot.

The Capricorn, or Goat, indicates a constellation of the zodiac. This constellation is crossed by the Sun from January 19th till February 15th.
In the order of the zodiac, the constellation is situated between the Sagittarius on the West and the Aquarius in the East. The Capricorn also indicates a sign of the zodiac corresponding to the sector of 30 ° of the ecliptic crossed by the Sun from December 21st till January 20th.

It is in this direction that it serves to the global location of the movement, still used in astrology.
The constellation is relatively easy to place with regard to big adaptations: it is situated on the straight and narrow which leaves the Great Bear, passes by the heart of the Dragon and by the head, to come to touch Vega de la Lyre, then Altair.

The Aquarius, or the water carrier. This constellation is crossed by the Sun from February 16th till March 11th. In the order of the zodiac, the constellation is situated between the Capricorn on the West and Fishes in the East. It is among the oldest constellations of the sky.
It is in a zone of the sky often called the Sea, because of its abundance of aquatic constellations such the Whale, Fishes, Eridan, etc. Sometimes, the river Eridan is drawn resulting from the jar of the Aquarius.

The Aquarius also indicates a sign of the zodiac corresponding to the sector of 30° of the ecliptic crossed by the Sun from January 20th till February 18th. The main axis of the Aquarius is situated in the Northeast diagonal / Southwest of the big square of Pegase, side the South. The constellation extends over this axis since the feet of Pegase up to the head of the Capricorn, marked by a pair of rather brilliant stars (the horns of the Capricorn, α and β Capr).

This constellation is crossed by the Sun from March 12th till April 18th. In the order of the zodiac, the constellation is situated between the Aquarius on the West and the Aries in the East.
Although rather big, it cuts a piece of the sky remote from the plan of the Milky Way and contains only few visible, however enough few brilliant stars.
Fishes also indicate a sign of the zodiac corresponding to the sector of 30 ° of the ecliptic crossed by the Sun from February 19th till March 20th.

It is in this direction that it serves to the global location of the movement, still used in astrology.
This constellation is very close of the Big square of Pegase, from which she can be tracked down if the conditions of visibility are sufficient.