Perseus, the Hero

Per

Persei

Sky Chart and Artist Rendering of Perseus

Origin:
Perseus is a very old fall/winter constellation. The constellation resides in a part of the sky where much of the royal family now lives.  Perseus is one of the 48 constellations described by Ptolemy in the Almagest (A.D. 140). Undoubtedly, the star pattern was recognized long before Ptolemy. Perseus was one of the many illegitimate children of Zeus, and some sources identify that his name tells of his lineage - "per Zeus." 

Information:
Perseus is not a very conspicuous constellation, especially in the skies of urban areas. For observers in the northern hemisphere north of 30° N lat., the stars are circumpolar and the constellation is high in the sky (nearly overhead) at 9 pm on Christmas Day. It may help to locate the Hyades of Taurus the Bull then scan in the direction of the pole star until you cross Capella (in Auriga). Finally, scan generally west from Capella to Algol. The Milky Way runs through Perseus so naked-eye, binocular, and telescopic viewing are all treats.

For the naked-eye observer, watching Beta Persei (Algol, the Demon Star), an eclipsing binary star system, change in brightness compared to its neighboring stars is an interesting study. Algol is normally magnitude 2.1 but fades to a dimmer 3.4 for about 10 hours then brightens again. The cycle is repeated at intervals about 2.9 days.

The binocular and rich-field telescopic viewer is not to miss the famous "Double Cluster" (NGC 869) at the border of Perseus and Cassiopeia.  Either open cluster would be a beautiful deep sky object alone, but when viewed together at low power (e.g., 15-20x) in binoculars or a rich-field telescope, the sight is stunning.

Perseus is known for the number of open clusters it contains - not fewer than 6 - and the several nebula.  There is even one nebula that looks much like the state of California known, appropriately enough, as the "California Nebula" (NGC1499).  Don't try to find it, though, without a large telescope or by photographing the area with high speed film.

Mythology:
Danaë was the beautiful daughter of King Acrisius of Argos. An oracle predicted that Danaë would some day bear the king a grandson who would someday try to kill him. To prevent his own demise, Acrisius hid Danaë in a bronze (or ivory) tower to prevent her from marrying and having children.  Zeus, knowing of her beauty, fell in love with Danaë and changed himself into a shower of gold dust so as to visit the now sad Danaë in her prison room by entering through the window (Acrisius built the tower with no doors). 

When he changed back to a familiar form, Danaë knew he was a god, but she didn't know which. Zeus told her that he wanted to her to be his wife and, in celebration of her accepting his proposal, could make this dark prison a wonderful sunny land with many flowers. 

Danaë accepted his proposal and her prison became sunny, green fields nearly as magnificent as the Elysian Fields themselves.  One evening, King Acrisius saw light coming out of the small window.  He instructed his servants to break down one of the walls and, as he walked into the tower, he saw Danaë with a baby -- Perseus, the son of Zeus -- on her lap.

Furious, Acrisius put Perseus and Danaë in a wooden chest and threw it into the sea. The wooden chest floated to the island of Seriphos, where the fisherman Dictys pulled it from the sea in his net.  Dictys took them to his brother King Polydectes (or Polydeuces) of Seriphos.  In one version of the myth, Danaë declined Polydectes proposal for marriage for which, in anger, Polydectes tried to get Perseus killed by tricking him to attempt to kill the deadly Gorgon Medusa.  In another version, Polydectes raised Perseus as his own son. 

In mythology, Perseus founded the city state of Mycenae, on the Peloponnesian peninsula, and become its first king.  However, he is best remembered for his many adventures; particularly, the killing of the Gorgon Medusa and the rescue of Andromeda from certain death by the sea monster (in some myths, Cetus the Whale). 

The Gorgons were three sisters: Euryale ("wide roaming"), Stheino ("strong"), and Medusa ("cunning one").  They were once very beautiful but Medusa committed an indiscretion with Poseidon one night in the temple of Athena.  The goddess Athena was so angered over the disrespect of her temple that she changed Medusa into a hideous creature with huge teeth and protruding tongue, claws in place of hands, writhing and hisssing black serpents instead of hair, large wings, and, worst of all, if one even glanced at the Gorgon they would be instantly turned to stone.

Suffice it to say, the horrible Medusa became a wanted creature; not for her friendship but for her head. Anyone who could chop it off would be an instant hero.  But no one was foolish enough to try -- until one day when Perseus made the insane promise to Polydectes that he would bring back the head of Medusa. (Different versions of the myth give different reasons for the promise: in one, it is a wedding present to Polydectes to demonstrate his faithfulness and fidelity to the King; in another, it is a casual comment as a show of his strength.)

So off he went on his foolhardy mission. For days he wandered, searching for the Gorgon women's cave. After searching for an interminable amount of time, he began to believe his quest  was hopeless. It was at this lowest point, while in the city of Samos, that Perseus found out exactly who he was. A tall woman, the goddess Athena, and her brother, Hermes (the messenger with winged sandals) appeared. The man said, "You are a son of Zeus. We have brought to you some things that may help you in slaying Medusa.  Take my winged sandals and the sickle which Cronos used to defeat Uranus, and Zeus used against mighty Typhoeus." "And here is my gift." said Athena, "Use my shield to reflect the image of Medusa so that you won't be turned to stone."  Hermes finished their interchange with, "You must find the Graeae and get them to tell you how to get to the Nymphs of the North, they will give you the Cap of Darkness (for invisibility) and a magic wallet [a large enchanted bag] and tell you how to find the Gorgons' lair."  Athena showed him a picture of Medusa so that he could distinguish her among the three, then the two gods left.

So it is that Perseus found the cave of the three Graeae women.  The Graeae shared a single eye for all three of them which they constantly fought over. Perseus hid behind some bushes at the mouth of the cave and watched them bicker over the eyeball.  When one took the eye out to give to another, Perseus grabbed the eye from them and said, "Tell me how to find the Nymphs of the North or you shall never have it back!" Reluctantly, they gave him the instructions to find the Nymphs, for which he gave them back their eye and flew off on his winged sandals. 

The Nymphs of the North gave him the Cap of Darkness and the Magic Wallet. They told him how to find the Gorgons' lair.  Exactly as they described Perseus found an island surrounded by rock statues in the shape of men. Perseus found the three Gorgons asleep.  With the Cap of Darkness on for invisibility, he looked at their reflections in his shield to carefully make sure he knew which one was Medusa.  In a single swift back-handed motion, he he sliced off Medusa's head with the sickle and, eyes-closed, threw the severed head into the magic wallet. Medusa's sisters woke at the noise and tried to find the invisible killer. He flew quickly away on Hermes' winged sandals and was not hurt.  

From the blood dripping from the severed head, the winged-horse Pegasus was born, the offspring of Poseidon and Medusa.  

On his way home to Seriphos he had many adventures.  In one, Perseus came upon the Titan Atlas carrying the weight of the world upon his shoulders (see another god's interaction with Atlas in the mythology of Hercules). Perseus felt sorry for Atlas and, by showing him the head of Medusa, turned him to stone so he could no longer feel the weight of his burden. 

Further on towards home, he saw what looked to be a statue chained to a rock.  Flying down he found not a statue, but a beautiful woman.  The beautiful maiden was Andromeda, chained to the rock by Poseidon for her mother, Cassiopeia's, vanity.  She was left as a sacrifice to a sea monster (Cetus in some legends). As she spoke of her sure demise, the sea monster rose from the sea. Perseus quickly made a deal with Cepheus and Cassiopeia; for rescuing the maiden he would win her hand. 

In one version of the myth, Perseus pulled Medusa's head out of the wallet and the sea monster turned to stone and crumbled to pieces. In another -- more exciting -- version, Perseus did battle with the sea monster using his sickle (or a sword) in which he would thrust and parry with his weapon while the sea monster would repeatedly attack and retreat. The ultimate outcome of both versions is that the sea monster was vanquished and  Perseus cut Andromeda's chains and took her to her father, King Cepheus of Æthiopia (Phoenicia).

Again, the myths diverge slightly about the events after the battle with the sea monster. In one version, Cassiopeia changed her mind about Perseus marrying her daughter.  In the argument that ensued, Perseus once again brandished the head of Medusa instantly changing the would-be in-laws to stone.

In another more pleasant outcome, Perseus formally asked for Andromeda's hand in marriage for which Cepheus gladly agreed. The parents threw a great feast and celebration, after which Perseus and Andromeda were married.  In time, the newlyweds set off for Perseus' home island of Seriphos. There they had a son, Peres, who is said to have given rise to Persians.

Perseus and Andromeda led a long, happy life together.

Later in life, Perseus, while throwing the discus during an athletic competition in Larisa, made a  stray throw which struck and killed a spectator.  The ill-fated spectator was none other than Perseus' grandfather, King Acrisius, thus fulfilling the prophecy, to the sorrow of Perseus himself. 

Perseus was ultimately killed by Dionysus. Perseus and Andromeda were honored in the sky by the goddess Athena. Poseidon honored his beloved Medusa by placing her among the stars. Medusa's head can be seen as the star Algol (Beta Persei).