Constellation of Perseus: Characteristics, Stars and Origin

The Constellation of Perseus (Referred to in scientific Latin as Perseus - whose genitive is Persei-, abbreviated as Per) is a boreal constellation that lies between the constellations of Cassiopeia, Auriga, Taurus, Aries and Andromeda.

Its main stars are the supergiant Algenib (also called α-Persei) and Algol (β-Persei), but include other more that form a total of 19 stars. Perseus is one of the most well-known constellations in the sky.

Constellation of Perseus

Main Features

Perseo is a constellation that to the South limits with Aries and Taurus, to the East with Auriga, to the North with Cassiopea and Camelopardalis (Giraffe), and to the West with Andromeda and Triangulum (Triangle).

Its asterism (group of stars that when viewed from Earth form a recognizable aligned image or pattern) consists of 19 main stars. It appears in the Northern Hemisphere, forms a polygon of 26 sides and has a straight ascension of between 1 hour 29.1 minutes (1h 29.1m) and 4 hours 51.2 minutes (4h 51.2m).

The declination coordinates in this constellation are around 30.92 ° and 59.11 ° (+45). Its night visibility is better in the month of December about 21 hours, between latitudes of + 90º North and -35º South (90º N 35º S).

Of the 88 modern constellations, Perseus ranks as the twenty-fourth largest of them (hence it is 24 in the ranking), occupying an area of ​​615 degrees square (615 deg2) in the celestial vault. Your quadrant is NQ1.

Stars that make up the constellation

In Perseus, as already said, there are 19 main stars in its asterism. The constellation has several known stars, being the most famous of them Algol, that comes from Arab Ra's al-Ghul ("Head of the Devil"); This one represents the eye of the Medusa that also is equivalent to the eye of Horus in the Egyptian mythology.

It is 92.8 light-years from Earth and has an apparent magnitude ranging from 3.5 to 2.3. Algol is in fact a binary stellar system, meaning that there are two stars orbiting together.

Algenib is the brightest star of Perseus; Is 590 light-years from Earth and its apparent magnitude is 1.79. The rest of the stars have different characteristics and, as with the other constellations of the universe, they are named according to the astronomical nomenclature, following the order of the Greek alphabet.

Only 7 of the 19 stars have planets around them, so these make up planetary systems like the one that is presided over by the Sun.

Celestial bodies related to Perseus

The constellation is slightly crossed by the Milky Way in which it touches Perseo's arm. Here, of course, there are many nebulae that are difficult to see in the telescope because of their faint glow; In some of them stars are formed due to the presence of a large molecular cloud that allows it.

Perseo, in fact, stands out for having in its interior a large number of galaxies of diverse forms, apart from supernovae and bubbles of gases.

The Perseids

It is the well-known meteor shower that crosses the vicinity of Algol, or β-Persei. This is one of the most numerous swarms of meteorites that occur between July 21 and August 19. His observation has taken place for over 2,000 years.

Etymological origin

The constellation Perseus owes its name to Greek mythology, in which this hero went through countless adventures that brought him to glory and his consequent immortalization in heaven.

Son of Danae and the god Zeus, Perseus was about to die assassinated by his grandfather Acrisio, who threw him into the sea with his mother because an oracle told him that he would die at the hands of his grandson. Perseus managed to survive with his progenitor on the island of Sérifos and was raised by Dictis, the fisherman.

Seriphos was ruled by King Polidectes, who commanded Perseus to bring him the head of Medusa the Gorgon. Perseus fulfilled his mission thanks to the divine help of Athena and Hermes, with which the hero beheaded Medusa.

Later, she saved Andromeda from being devoured by a sea monster and did the same with Danae and Dictis, who feared Polidectes. Therefore, Perseus taught the head of Medusa to this ruler and turned it into stone next to his entourage of followers.

Following these feats, Perseus returned to his homeland, Argos. Nevertheless, Acrisio did not trust in the reconciliation with Perseus, reason why it fleees to another country and appears like spectator in funeral games.

In these, it happened that Perseo participated in the discus throwing and accidentally wounded Acrisio to death. After the funeral ceremonies, Perseus remained king of Tiryns. At his departure, Perseus became a constellation with Andromeda, his parents and the monster.

Historical review of your observation

As can be seen from the above, the astronomical observation of the constellation Perseus was already known in Classical Greece. However, Perseus was also seen in ancient Babylon, as recorded on his tablets, in which are recorded more or less the same set of stars as the Greeks had seen.

The Babylonians, like other civilizations that inhabited Mesopotamia, knew of their existence and their position in the sky toward the year 1000 BC.

The Chinese, who also developed astronomy, scrutinized the cosmos for more than two millennia, but did not catalog the stars before the Tang Dynasty (618-907).

At this time in their history, the Chinese put their other names for what in the West was known as Perseus, and with different connotations; For example, Tiānchuán ("Heavenly boat"), Jīshuǐ ("Raised Waters"), Dàlíng ("Great trench") and Jīshī ("Pila de coráveres").

In the Polynesian culture Perseus was not distinguished as a separate constellation, except for the natives who inhabited the Society Islands, in the middle of the Pacific Ocean, who called it Faa-iti, the"Little valley."

Perhaps the Maori called Matohi or Tangaroa-whakapau to the star Algol of this constellation to refer to the celestial signals that appear and disappear when there are changes in the tides, which indicates the use of the aboriginal astronomy in the navigation.


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