The constellations are groupings of stars, whose position in the night sky adopts imaginary figures do not vary; These figures are formed by drawing imaginary lines between the stars. Their names derive from ancient civilizations of Greek, Latin or Arabic origin; and in general, the constellations are usually separated into two groups, according to the celestial hemisphere: northern , located north of the celestial equator, and southern , located to the south.


What are constellations?

Constellations are a group of stars, whose position in the night sky form silhouettes of imaginary figures, objects or animals. Currently, there are 88 constellations in the celestial sphere , some can be seen throughout the year and others at specific seasons of the year. The best known are the constellations of the zodiac.



  • Their names are due to the imaginary figures that form animals or objects and depend on the culture or mythology.
  • The stars that make up the constellations can be hundreds of light years from each other.
  • They help us locate the stars .
  • There are 88 constellations in the celestial sphere.


It is known about the first groupings of stars, in Mesopotamia , 4000 years BC, such as Leo, Taurus and Scorpio ; but in itself little is known about the origin of the constellations, since they originated thousands of years ago. They were first used to guide navigators, for example, from the Big Dipper you can find the pole star and thus know where the north is. They were later used for calendars for agricultural and religious purposes.



Ancient constellations

  • It is difficult to know the real origin of the ancient constellations, despite this, there are records from the year 4000 BC of the constellations of Leo, Scorpio and Taurus in Mesopotamian culture , although with other names.
  • The zodiacal constellations originated in Babylon in the 6th century BC, then were adopted by the Greek culture, who baptized them with their current names.
  • Claudius Ptolemy in the second century BC made a compendium written in Greek, his work was called Almagest and grouped 48 constellations.
  • In the years 700 AD, the constellations of the Big Dipper, Capricorn and Sagittarius were described in China in the book of The sky was divided into 31 regions, of which 3 occupied the high latitudes and the rest occupy the zodiac zone.
  • The Hindus called the constellations ” nakshatra “. They divided the sky into 27 parts, each representing a division of the ecliptic similar to that of the western zodiac. All of this was described in the Vedic texts as: Shatapatha Brahmana and Vedanga Jyotisha of Lagadha
  • The Incas classified them in stellar or brilliant constellations formed by individual stars that united to the western way they formed figures; and dark or black constellations that were visualized as spots in the Milky Way .
  • The Incas used the constellations to set calendars and build their cities.

Modern constellations

  • The Arab astronomer Abd Al-Rahman Al Sufi , described Sagittarius in the year 964 in his book of the fixed stars.
  • The compendia of Ptolemy were mostly lost and it was the Arabs who inherited the Almagest and completed their research . After many years, in the Middle Ages works of Ptolemy could be recovered in Europe .
  • New constellations were devised in the 16th century by European sailors exploring the south.
  • Johann Bayer published the first astronomical atlas to cover the celestial sphere in his work Uranometria , in 1603 . He added 12 more constellations to those described by Ptolemy, these were: Indus, Musca, Pavo real, Phoenix, the southern triangle, Tucana and Volans

Other European creations

  • In 1624, the German astronomer Jakob Bartsch devised five new constellations: Unicorn, Giraffe, Crux, Tigris, Jordanus.
  • In 1643, Anton de Rheita , proposed a constellation Musca Borealis, which later in the reign of Louis XVI was called Lilium .
  • In 1679, in France , the astronomer Augustin Royer created the constellation Columba and Scepter.
  • Gottfried Kirch created a second Scepter south of Eridanus in Prussia.
  • Johannes Hevelius proposed the constellations of Taurus, Canes Venatici, Lacerta, Leo Minor, Lynx, Sextans, Vulpecula, Scutum.
  • Hevelius proposed others, these were: Cerberus, Mons Maenalus, Triangulum Minor,
  • In 1763 the astronomer and mathematician Nicolas Louis de Lacaille , published his work Coelum australe stelliferoum where he proposed constellations with names of human creations, instead of animals or mythological figures, such as; the compass , the clock , the oven , plateau , microscope, the ruler, the telescope , among others.

How many constellations are there

In 1928, the International Astronomical Union officially grouped the celestial sphere into 88 constellations , being named after the figures of animals, religious or mythologies.

The best known are those that are displayed on the earth plane, such as: the constellation of the zodiac, the constellation of the Southern Cross and the constellation of Hydra .


  • Circumpolar: observed in the Northern Hemisphere throughout the year, such as Ursa Major and Ursa Minor .
  • Spring constellations: their name is due to the fact that they are displayed at this time of year, such as those of Crater , Leo and Hydra .
  • Summer constellations: like the Swan and the Little Horse .
  • Autumn constellations: they are very far from our Milky Way like those of Andromeda , Aquarius and Pegasus .
  • Winter constellations : like the constellation Gemini .

Constellation names

Leo, Scorpio, Taurus, Andromeda, Aquarius, Eagle, Aries, Cancer, Canis Major, Can Minor, Capricorn, Centaur, Hydra, Crater, Dolphin, Libra, Gemini, Hercules, Prion, Pegasus, Perseus , Pisces, Sagittarius, Virgo, Ursa Major, Ursa Minor, Cruz, Lynx, Dorado, Grus, Musca, Indus, Hydrus, Carina, Norma, Octans, Pictor, Puppis, Pyxis, Telescopium, Vela, Pavo, Tucana, Apus, among others.

What are the constellations of the zodiac

The word zodiac comes from the Greek zodiakos , which means circle of little animals . The zodiac is a line in space where the planets and the Sun pass . This is divided into twelve constellations that correspond to twelve signs.

  • Aries: it is located between Pisces to the west and Taurus to the east. The Sun passes through this constellation between April 19 and May 13. It is made up of stars of medium brightness and highlights Sheratan, Hamal and Mesarthim .
  • Taurus: it is located between Aries to the west and Gemini to the east. The Sun passes through this constellation between May 14 and June 19.
  • Gemini: It is easily located by the stars Rigel and Betelgeuse in the constellation Orion. The brightest stars in this constellation are Pollux and Castor .
  • Cancer: it is located close to Gemini and is formed by stars of weak brightness, such as Acubens, et β Can, Asellus Australis, Asellus Borealis and X Can.
  • Leo: it is located between Cancer to the west and Virgo. The Sun passes through this constellation between August 10 and September 16. It is best seen in spring and its brightest star is called the Regulus Lion
  • Virgo: the Sun passes through this constellation between September 16 and October 30. It is observed from the northern hemisphere.
  • Libra: it is located between Virgo to the west and Scorpio to the east. The Sun passes through this constellation between October 31 and November 22.
  • Scorpio: it is located between Balance to the west and Sagittarius to the east, in the southern hemisphere. The Sun passes through this constellation between November 23 to November 29.
  • Sagittarius or Sagittarius: his name means the archer. It is situated between Scorpio to the west and Capricorn to the east. The Sun passes through this constellation between December 18 and January 18. The constellation is easily recognizable by a teapot-shaped asterism.
  • Capricorn or Goat: it is located between Sagittarius to the west and Aquarius to the east. The Sun passes through this constellation between January 19 and February 15.
  • Aquarius or the water carrier: it is located between Capricorn to the west and Fish to the east, in an area called Sea, the name of the area is due to the aquatic constellations. The Sun passes through this constellation between February 16 and March 11. It is one of the oldest constellations in the sky.
  • Pisces: it is located between Aquarius to the west and Aries to the east. The Sun passes through this constellation between March 12 and April 18 . It is a fairly large constellation with dim stars and is far from the Milky Way.

Which ones are visible in the northern hemisphere and in the southern hemisphere

  • Northern Hemisphere: Ursa Major, Ursa Minor, Cassiopeia, Andromeda, Dragon, Boyero, Lyre, Swan, Orion, Big Dog, Taurus, Lynx and Triangulum.
  • Southern hemisphere: Antlia, Caelum, Can Minor, centaurus, Columba, Corona Australis, Corvus, Eridanus, Fornax, Hydra, Lepus, Lupus, Microscopium, Pisces, Austrinum, Puppis, Pyxis and Sculptor.


Formerly, these imaginary figures that today we call constellations, were useful for navigation or night travel , they were also used to follow the course of the seasons of the year and to develop agricultural and religious calendars . Today, the constellations have allowed us to create a map of interstellar space , to fix the location of stars, planets and galaxies.

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