Andromeda in chains
I don't know what it's like, but putting this title in my mind the beautiful (even if a bit dated) song by Tears for Fears titled "Woman in chains"... I'm listening to it right now... But let's start with Astronomy, with this maiden daughter of Cepheus and Cassiopeia (in fact I already mentioned her talking about the constellation "W"), chained to a rock near the sea as a sacrifice to Poseidon to atone for the sins of her too vain mother, guilty of having claimed that her daughter was even more beautiful than the Nereids... The poor thing would have ended badly if Perseus (who had just beheaded the Medusa) had not arrived at the last moment. To make a long story short, our hero with his sword stabs the sea monster and frees (how? it is not known ...) the unfortunate who would later become his wife and mother of six children ...
As a complete inexperienced in the field (both mythology and art) I found on Wikipedia that for example the Flemish painter Rubens had made an oil painting "Perseus and Andromeda", in which two cherubs freed the damsel, while ours observed the scene surrounded by three other cherubs holding the Medusa's head, the helmet and the horse (Pegasus)... Instead in a work by Vasari it is Perseus himself who frees Andromeda, while from the blood of Medusa's head resting on the ground corals are born... In short, a mixture of legends and mythological stories in which we find many constellations that sooner or later we will know...
The name, history and myth of Princess of Ethiopia
Tradition links the figure of the goddess Mother Earth to the stars of this constellation.
The antecedent of the terrible story of Andromeda chained naked on a rock on the coast near Joppe (Jaffa, the ancient port of Palestine) and given as a sacrifice to the sea monster Ceto (Whale) is linked to the myth of another constellation, that of the vain queen Cassiopeia. This moved the wrath of Poseidon, the god of the sea, when he came to compare himself to the Nereids, the nymphs of the sea, daring to even claim to surpass them in beauty. The god brought down a seaquake on the coast, and later sent a sea monster, Ceto. The husband of Cassiopeia, King Cepheus, worried turned to the oracle of Ammon (Egyptian god Amun, who resided in Siwa, an oasis in the Libyan desert) to know the causes of the divine anger, and ask what was the way to appease it. When he heard the answers, upset, he learned that the only way to quell his anger was to immolate his daughter Andromeda to the monster Ceto.
Andromeda bravely accepted his fate. And as if it was the occasion of a party, she was decorated with the most precious jewels, dressed in the most beautiful dresses and perfumed with the most precious essences. Having arrived in procession on the shore, the ceremonial began: open her delicate arms she was tied to the cold rock. Fiera assumed a composed attitude, lifted her head and shook her shoulders, her dress slipped, leaving her bust naked, covered only by long hair. Silence fell. For a moment in front of so much beauty the sea seemed to hold back the waves, suspended. The martyrdom was about to take place.
While Andromeda lay helpless and chained, the mortal son of Zeus, Perseus, arrived at the rock chosen as the altar of sacrifice on his return from the killing of the gorgon Medusa, riding the winged horse Pegasus (in some versions, with sandals donated by Athena). Approaching the rock, the hero was kidnapped by the beauty of the virgin Andromeda, so elegant in her soft crying. He asked her the reason for his condition. He learned the causes, revealed to him with shame only after considerable resistance, he immediately offered to fight against the sea monster in exchange for the promise to marry her. So the wise King Cepheus, father of Andromeda, agreed. Then Perseus confused Ceto by casting his shadow into the sea, the monster emerged and found himself before the armed hand of the boy who struck the mortal blow. Perseus freed Andromeda. The plot of the myth, however, hides dark and disturbing implications, the name "Andromeda" itself offers a clue, its meaning is "dominatrix of men". As the poet Manilius (1st century B.C.) quotes.) " [...] the winner of Medusa was won at the sight of Andromeda", in this perspective perhaps the princess of Ethiopia is not a completely passive and weak figure, she seems rather similar to Aphrodite, as an expression of desire, and the Mesopotamian roots of the myth would confirm it: in ancient times the constellation was dedicated to the Egyptian goddess of love and war, whom the Babylonians called Ishtar, represented as a sensual and sex hungry sea goddess, worshipped in temples along the coasts of Palestine: the very places of Andromeda's failure to sacrifice.
Andromeda in the sky
In the introduction I said that the constellation of Andromeda (with few bright stars) is well recognizable starting from the Square of Pegasus: thanks to Stellarium we see that just one star of the square is instead α And, Alpheratz (also known as Sirrah) from which to the left we go on with other three stars (respectively δ, β and γ1) to form an improbable "chained princess", to which we will come back soon.
But since we are talking about galaxies, let's dwell for a moment on three other really beautiful objects: let's start with a nice open star cluster (NGC 752), visible to the naked eye, but spectacular already with good binocularsFor those who don't know how to find the Andromeda Galaxy in the sky, I have highlighted in this other photo the position of the nebula: it's not a mistake of Stellarium, the Galaxy (otherwise known as M31) is really huge and especially in the mountains you can see it with the naked eye like an oblong and soft wad of white cotton. When I happen to show it to friends I always start from the square of Pegasus, I show the three bright arched stars, then starting from the central one I make to climb upwards along the two indicated stars and then immediately to the right there is our goal: with a good pair of binoculars you can already recognize well the elliptical shape of this that is the brightest Galaxy (about magnitude 4) and therefore visible to the naked eye.
From a much more powerful eye, that of the Hubble Space Telescope, the Galaxy shows itself in all its magnificence.
Here instead we see another absolutely exceptional galaxy (NGC 891), which owes its notoriety to the fact that it is exactly cut with respect to our view: once again in the photo of the Hubble Space Telescope and in its enlargement we can enjoy all the details.
Let's close this mini-review of spectacular photos, always of the Hubble Space Telescope, with another jewel, this time visible with instruments of at least 20 cm: it's NGC 7662, a planetary nebula, which also received the nickname of Snowball (Snowball). Also in this case we can see here the enlargement that shows a lot of breathtaking details.
The stars of Andromeda
In the constellation we are analyzing, there are no stars of monstrous proportions, only discreet values for some of them: in the diagram I reported the biggest one (γ1 And, Alamak, well 100 times our Sun) and other four others all bigger than the usual well-known stars, but already for a long time resized to the rank of any star... When I had pointed out to my friends Rigeliani and Albebaranini that their stars, beautiful in our sky, they were constantly outclassed by other unknown stars, their first reaction was that they turned blue and green in the face respectively because of anger, but then they made shrugs, or rather shrugs and triple shrugs, since they had four and six arms.
This time (returning serious, but I can't do anything about it if my friends scattered around the universe have strange somatic characteristics) of the biggest star (γ1 And) I propose a real photo, that shows the double star composed by a primary (γ1) of a nice orange color, accompanied by the secondary (γ2) of a nice bluish color, as they appear photographed by a good telescope. Actually the secondary component is triple with two other smaller components, a reddish and a yellowish one.
Andromeda with few names
Let's see now the few names of the few stars of the constellation Andromeda: three brighter stars and therefore three names, plus a few others found here and there on the internet.
- Alpheratz (α And): also called Sirrah, both with the meaning of navel of the horse, from Arabic
- Mirach (β And): from Arabic, the belt
- Alamak (γ And): from the Arabic, a strange desert lynx that frankly has nothing to do with the
- Adhil (ξ And): from Arabic, it means the train, which, with a princess chained to a rock, is like a cabbage snack.
- Sadiradra (δ And): from Arabic, nice name but of unknown meaning
- Adhab (υ And): from Arabic, same as above and not even the Upsilàndibi could solve the mystery
As I was saying, apart from the first three names that are quite well known and used, I must say that I have already forgotten about the others...
When can we observe Andromeda?
It is a constellation that can be seen very well at our latitudes: at the standard time to show it to friends without grumbling or runaway (9 p.m.), Andromeda is visible at NE low on the horizon around mid-August. It culminates almost at the zenith in the second half of November (this is the absolute best time to observe M31, this time almost exactly at the zenith), while finally we find it low on the horizon, at NW, in the following month of March.
In short, a beautiful span of time in which it is visible from our skies.