Ephemeris Extra – The Great Star Story of Autumn

The constellations of the great star story of autumn. Looking southeast on October 31 at 10 p.m. Created using Stellarium.

The great star wheel of the sky rolls on. In the evening sky gone are the stars of spring, and going are the southern stars of summer. In the morning sky before sunrise the stars of an early winter evening.

A constant in both skies are the stars of autumn: rising in the evening and setting in the morning. In no other part of the sky do so many constellations take part in a single story

The constellations, as seen above are Cepheus, Cassiopeia, Andromeda, Perseus, Pegasus, and Cetus. And their story goes like this:

In distant Ethiopia a crisis was brewing. King Cepheus and Queen Cassiopeia were at wits end as how to stop it. A giant sea monster named Cetus was ravaging the country’s coastal cities destroying them and devouring the inhabitants.

The king and queen consulted the temple oracle as to what happened and what could be done to save their country. The oracle intoned gravely that the fault was Cassiopeia’s. Suddenly the queen knew what happened. Cassiopeia was very beautiful and she had vainly boasted to all who could hear that she was more beautiful than even the sea nymphs, the lovely daughters of the sea god Poseidon.

The sea nymphs had heard of Cassiopeia’s boast and complained to their father. Poseidon, like any father, was angered, and being a god was able to do something about. Being a god means never having to say your sorry when you do something really mean. He loosed the monster Cetus upon the Ethiopians.

The oracle said that to appease the monster and Poseidon Cassiopeia would have to sacrifice her daughter the Princess Andromeda to the monster. That is how young Andromeda was chained to the rocks on the sea shore to await her doom…

Far away in ancient Greece a wedding was about to take place between the beautiful Princess Danaë and King Polydectes. Danaë’s son Perseus, fathered by Zeus, but that’s another story, wasn’t too happy about the proposed union, and Polydectes wanted the boy gone.

When Perseus asked Polydectes what he wanted for a wedding gift, he said, “I want the head of Medusa.” The boy immediately and foolhardedly agreed to get it for him.

Merdusa, it turns out, was one of three sisters, the Gorgons, who had snakes for hair. They were so ugly that one glimpse of them would turn the beholder to stone. Medusa was the only mortal one.

Luckily Perseus had the favor of the god Hermes and Athene. They armed him with Hermes’ winged sandals, a helmet that made him invisible, a pouch that would expand to hold an object of any size, a shiny mirror shield, and a sword.

Thus armed Perseus was told to find the Graiae or the gray women, who could tell him where the lair of the Gorgons was. They were three in number and shared but one eye and one tooth among them which they passed from one to another to use.

The Graiae refused to help Perseus. But he was able to force them to help by snatching their one eye while it was being passed from one to another. They told him that the Gorgons dwelt in the shore of the river Ocean at the edge of the world in perpetual twilight.

In approaching the lair of the Gorgons Perseus put on the helmet of invisibility. He approached Medusa stepping backwards, cautiously peering only at Medusa’s indistinct image in his shield. Perseus then swept his sword in a backhanded way and managed to sever Medusa’s head. It is said that Athene guided his hand.

Amazingly, springing full grown from Medusa’s blood was the winged white stallion Pegasus. After placing Medusa’s head in the pouch, Perseus mounted Pegasus for the trip home.

Cruising high in the sky over the Ethiopian coast Perseus spotted a horrific sight. There far below the beautiful Andromeda, in chains; her screams reaching his ears. Then he spotted why she was screaming. A short distance away, crawling out of the surf was the monster Cetus, heading towards Andromeda. Perseus immediately sizes up the situations and swooped with Pegasus down to a spot between Andromeda and the monster. Then, burying his head in his shoulder drew out the head of Medusa from the pouch and held it in front of Cetus. The head was as lethal in death as in life, and the monster was promptly turned to stone. Replacing the head in the pouch, Perseus freed Andromeda. They flew off to, well supposedly, live happily ever after.

Oh yes. Perseus did present the head of Medusa to his step father Polydectes. He, of course, was also turned to stone when he laid eyes on it.

There you have it a story connecting the autumn constellations of Cepheus, Cassiopeia, Andromeda, Perseus, Pegasus and Cetus.

Cepheus is a dim church steeple of a constellation. Its dim star Delta is a variable star, the prototype of an important class of distance measuring stars called Cephieds in its honor. Cassiopeia is the famous W shaped constellation that along with Cepheus doesn’t set at our latitude.

Perseus looks to me more like the cartoon roadrunner than a hero. As the ancients saw him, he is holding the head of Medusa, whose still glittering eye is the star Algol, a variable star which ghastly winks at us every 2 days and 21 hours.

Andromeda’s modern claim to fame is the great galaxy that lies beyond her stars, the Great Andromeda Galaxy which has the designation M31. The galaxy is faintly visible to the unaided eye on dark nights. The farthest you can see without optical aid. The galaxy lies some 2.5 million light years away.

Pegasus can be easily found by the square of stars the form his body. It’s called the Great Square of Pegasus.

What can be said about Cetus. It now represents a whale, not a monster. Its star Mira, which means “Wonderful”, slowly varies in brightness over 330 days from a star barely visible in binoculars to a 2nd or 3rd magnitude star.

Look up on an autumn evening and recapture the wonder the ancients had as they looked upward at the stars.