Taken together, several autumn constellations tell one of the most remarkable stories in ancient mythology.

The ancients fashioned their heroes out of the stars, and their exploits teach us much about bravery and personal sacrifice for the larger good of society.

Nearly overhead in the northern sky is the constellation Cassiopeia. She is “W” shaped and looks like a partially folded up chaise lounge. In modern times, she is often called “the lady in the lawn chair.”

Cassiopeia was the beautiful queen of Ethiopia, and she was vain about her looks.

While combing her luxuriantly long hair one day, she boasted that she was even more beautiful than the Nereids, the nymphs who lived in the sea.

There were 50 Nereids in all. They were the daughters of Nereus, sometimes called the Old Man of the Sea. Unfortunately for Cassiopeia, one of them, Amphitrite, was married to Neptune, the god who ruled over the sea. Amphitrite led a deputation of the Nereids’ sisters appealed to Neptune to punish Cassiopeia for her vanity.

Neptune didn’t exactly enjoy hearing his nymphs put down that way, especially by a mere mortal, so he sent the vicious sea monster Cetus to ravage the coast of Ethiopia. Right now, you can see it stretching across the southern sky, low on the horizon, in the early evening.

Many astronomy types think of Cetus as “The Whale,” but the Greeks and then the Romans envisioned it quite differently. By our modern standards, the Greek Cetus was rather ridiculous looking — the denizen of some B-movie Japanese monster flick from the 1950s.

It had enormous gaping jaws, the front feet of a land animal, and a scaly, coiled body like a sea serpent. Add the tail at the end, and the result is almost comical — except of course for the big, pointy teeth.

What were the Ethiopians to do? The country needed a decisive leader, but unfortunately, it didn’t have one. Cassiopeia’s husband was the rather weak King Cepheus, who is fittingly placed below Cassiopeia in the northern sky.

Cepheus was a distant relation to the nymph Io, one of Jupiter’s many illicit paramours. He was also the king of Ethiopia. However, his kingdom did not correspond to the modern-day country. Instead, it contained parts of modern Israel, Jordan and Egypt.

Did King Cepheus march out with an army to defeat the sea monster? Nope. Instead, he went to see a fortuneteller, or more specifically, an oracle, a person through whom the ancients believed the gods spoke.

The oracle told him that the only way to soothe the wrath of Neptune was to sacrifice his daughter, the modest and beautiful Andromeda, to Cetus by chaining her to a rock so that the sea monster could have her for lunch.

Andromeda was as different from her vain mother as the day is from the night. Dutifully, she agreed to die so that her parents’ kingdom could be saved. Cepheus tearfully agreed to sacrifice his own daughter, which made him the greatest wimp on record.

And thus the stage was set near the ancient city of Joppa, where the modern city of Tel Aviv is today.

The fair and frail Andromeda wept with fear. Her parents stood weeping on the shore. Apparently, a lot of weeping was going on as monstrous Cetus advanced rapidly, cleaving the sea like an enormous ship.

Ethiopia needed a hero and fast, and it got one. Perseus was no wimp. He was the kind of hero who most appealed to the ancients — half human and half god, son of Jupiter and a mortal woman, who again was not his wife. (As you can see, Jupiter got around.)

In the autumn sky, Perseus is to be found in the northeast almost straight overhead. He looks like an upside-down “Y” in the sky.

Among his accomplishments was the slaying of the snake-headed woman Medusa, who was so ugly that her visage turned the viewer to stone. Perseus carried her head with him in a sack everywhere he went. You never know when something like that might come in handy.

Here is where the story gets a little weird, that is if you didn’t think it was a little weird already.

Fresh from the slaying of Medusa and with her gory head still in its sack, Perseus happened to pass by and saw Andromeda chained to the rock.

At first, Perseus thought that she must have been a marble statue. No living human could possess such innocent beauty. He instantly fell in love with the beautiful damsel in distress — rock, chain, and all.

Now Perseus was the kind of guy that most parents dream their daughters will bring home for dinner. As the voracious monster descended upon her, he politely inquired about her name and her exposed circumstance.

Andromeda did not reply at first. For starters, she was the shy, retiring sort. In the Roman poet Ovid’s wonderful version, so bashful was she that she would have raised her hands to cover her face shyly if they had not been chained to the rock.

One can imagine the scene thusly:

Perseus: “Greetings fair damsel, potentially in distress. My name is Perseus. May I inquire as to your name? I know it’s none of my business, but why are you chained to that rock?”

Andromeda: Inarticulate weeping followed by stunned silence.

The enamored and oblivious Perseus persisted in his questioning, and Andromeda finally found her tongue. However, she interrupted her story with a scream of terror as she spied the advance of Cetus upon them.

The great hero Perseus knew what to do. According to the Roman poet Ovid, he returned to the shore and politely asked Cassiopeia and Cetus for their daughter’s hand in marriage. Only then did he fly upward to slay the beast. What a guy!

The popular version of the myth, depicted in the movie Clash of the Titans, shows Perseus taking flight on the winged horse Pegasus, which is also among this group of constellations.

However, in the original myth, Perseus rises on a pair of winged sandals given to him by Mercury, who was the messenger of the gods and is often depicted wearing such footgear.

In the most ancient story, another heroic character named Bellerophon, not Perseus, was the tamer and custodian of Pegasus. In the sky, Andromeda, not Perseus, is riding on the back of Pegasus.

What gives? The Perseus/Pegasus connection evidently developed slowly and didn’t become the standard one until the western medieval period, centuries after the original myths were told.

Anyway, Perseus flew upward in some way or another to confront Cetus.

Despite the risk to his life, he jumped on the monster and repeatedly hacked away with his diamond-hard sword until it died. The onlookers onshore, mostly local villagers, applauded enthusiastically as Perseus released Andromeda from her chains and presented her to her relieved parents.

Meanwhile, Cetus floated on the sea like the waterlogged hulk of a ship. The local inhabitants hauled the corpse onto the land, skinned it, and put its bones on display.

Cassiopeia and Cepheus prepared an extravagant wedding banquet for the betrothed couple. There is no record as to what was served for dinner. My guess is roasted monster meat.

Tragically, Andromeda was already betrothed to her erstwhile boyfriend Phineas, the headstrong brother of King Cepheus. As the banquet progressed, Phineas and a large group of his pals burst upon the scene, demanded that Andromeda be turned over to them, and threatened violence if they didn’t get what they wanted. Cepheus refused and then slunk away, mumbling that he had done the best he could.

A gory battle ensued. Since this is a family newspaper, I will not describe it here. For the details, please read Book V of Ovid’s Metamorphoses.

Suffice it to say that Perseus single-handedly hacked most of his attackers to death with that diamond sword of his. When he tired of the battle, he simply removed Medusa’s head from its sack and turned the rest of the offending wedding guests to stone.

Andromeda and Perseus flew away on Pegasus, presumably to live happily ever after.

Andromeda bore many children by Perseus. Notable among them was Perses, the progenitor of many subsequent kings of Persia.

When all the principal characters died, the gods put them in the heavens, where they remain to this day.

Cassiopeia endlessly circles the celestial pole. She often hangs upside down as she plunges below the horizon.

Her vanity is thus appropriately punished. From Greece, she appears to get a good upside-down dunking as she descends into the sea. Her hair, the centerpiece of her vanity, must be an absolute mess.

Her weak-willed husband, King Cepheus, hangs nearby and suffers the same indignities.

Perseus still clutches the head of Medusa in his upraised hand. Her noggin is represented by the odd star Algol, which means the “Demon’s Head.” About every three days, the light from this “variable” star dims for about ten hours. It is as if the evil eye of Medusa still slowly winks at the world.

Near Andromeda’s head is a cigar-shaped streak of light called the Andromeda Galaxy. It is easily visible to the naked eye and must have been apparent to the ancients. We know now that it is an “island universe,” like our Milky Way galaxy, a pinwheel of hundreds of billions of stars like our own sun.

So if we need to find heroes to look up to, we simply have to look up. The night sky is full of them.

Perseus shows us that bravery is looking into the face of overwhelming odds and acting for the common good.

But the true hero of the story is Andromeda. She willingly faced a horrible, certain death to save the lives of her people. For that reason, the gods gave her a place of honor. She rides slowly across the sky upon the back of the winged horse Pegasus, the cold star wind in her face and the 300 billion suns of the Andromeda galaxy decorating her wind-swept hair.