According to mythological accounts, Andromeda was the wife of Perseus, with whom he had seven children. Daughter of Cassiopeia and Cepheus, was given by her father to Keto, although she was rescued by the aforementioned Perseus.
The mythology mind that Cassiopeia provoked the anger of Poseidon when she presumed to be more beautiful than the Nereids. The God from the waters he decided to send the monster Keto to end humanity. In this frame, Cepheus discovered through an oracle that the only way out was to deliver his daughter Andromeda to Keto, for which he chained her to a rock. When Perseus saw Andromeda, fell in love with her and asked her parents for her hand. Thus freed Andromeda and then beat Keto.
Once Andromeda passed away, mythology states that Athena placed it in a stellar constellation. from this one on idea, the concept of Andromeda as understood in the astronomy.
Andromeda, in this context, is the name of a constellation containing a galaxy of the same name, although in a technical field the latter is known as Messier 31, NGC 224 or Spiral Galaxy M31. It is a colossal spiral whose diameter exceeds two hundred and twenty thousand light years and in its range there are about a billion stars.
The Andromeda galaxy is, for most observers, the farthest object that we can easily see from our planet; However, there are those who say that this title belongs to the triangle galaxy, which is even further away (specifically, 2.5 million light-years in the same address than the previous).
It is known by the name of Local Group to the cumulus of galaxies in which the Milky Way is found along with thirty-two others, including Andromeda, the largest and brightest of all. As a curious fact and, for some, worrying, scientists have observed that Andromeda is constantly approaching our galaxy at a speed of 300 kilometers per second, which means that in about five billion years at most there will be a collision between the two that will result in a merger from which a supergiant elliptical galaxy will emerge.
It has not yet been possible to calculate exactly the mass total Andromeda, and for this reason the values that we find in specialized sources present a wide range. While certain scientists claim that our galaxy contains a quantity of dark matter much higher, some recent studies have revealed the exact opposite. Dark matter is that which does not emit any kind of electromagnetic radiation or is related to it, but is absolutely transparent throughout the electromagnetic spectrum; it is estimated that it represents 27% of the universe.
Another of the characteristics that some specialists attribute to the galaxy Andromeda is her high level of brightness, so much so that only one of those known to man can surpass her in this regard. On the other hand, given the orientation it is in with respect to our observation points, it is not easy to carry out the calculation of its luminosity, and this gives rise to different results, depending on the method used. Still, scientists generally agree that it at least outperforms our galaxy in luminosity.
It is worth mentioning that Andromeda It is also the name of a gender from shrubbery to which medicinal properties are attributed; the denomination of a mountain which is located in Canada and whose height reaches the 3,450 meters; and the title of a TV series that aired in USA Come in 2000 and 2005.