The oceans represented enormity and danger to the ancient Greek people. As they looked south into the great waters of the Mediterranean, they invented a pattern of stars that represented the awe and fear they felt.
Low in the southern sky this month is the mighty Cetus, the “Whale.” The constellation seems to rise out of the sea for Greek coastal dwellers.
Before midnight, you can find him spread out over a large expanse of the southeastern sky. A rough circle of five stars forms his large head. He has a long, skinny body formed by a line of stars stretching to the west and ending in a rather fat tail.
Our modern identification of him as a whale is kind of fishy. The Greeks couldn’t have had much experience with whales. More likely, they saw him as a sea monster who breached, slowly and majestically, from the waters in the late summer and dove back in the late winter.
Eighteenth-century star maps picture Cetus as a weird combination of different animals. It has an enormous head, with its large open mouth and rather formidable-looking teeth. He has claw-like front feet and a scaly body like a lizard. His body ends with a long, curved tale like a sea serpent.
He acted as a grotesque and scaly hitman for Poseidon, the god of the sea. His greatest battle is a whale of a good story, a tail, er, tale, of bravery and self-sacrifice.
He is the featured villain of the Perseus/Andromeda story. Such was its importance to the ancients that every significant character appeared in the sky as a constellation.
Cassiopeia was the Queen of Ethiopia. She is visible as a “W” of stars high in the northern sky. She spouted off that she was more beautiful than the Nereids, handmaidens to Poseidon.
Surly Neptune didn’t have a sense of humor about such matters, so he sent Cetus to ravage the coastline of Cassiopeia’s domain.
Andromeda, Cassiopeia’s daughter and a constellation visible in the eastern sky, was chained to a rock near modern Tel Aviv to act as a mid-afternoon snack for the monster. In that way, it was hoped that Neptune’s anger would be assuaged.
Andromeda faced her fate without blubbering. Luckily for her, the great hero Perseus, located just east of Cassiopeia in the sky, came flying down on the winged horse Pegasus, just to the south of Andromeda.
He dispatched Cetus, saved the innocent Andromeda, and married her.
The Ethiopians no doubt had an enormous fish dinner at the wedding. One can imagine the solicitous Cassiopeia asking Perseus, “And how do you like your sea monster, dear, delicately poached in butter or deep-fried with a side of tartar sauce?”
Cetus possesses a variety of astronomical objects to observe. The most famous object is the star called Mira, about which we will have more to say next week. Teaser: Its name roughly translates from Latin as “The Wonderful.”
Although it isn’t much to look at, the star called Tau Ceti is quite similar to our own star, the sun. Easily visible to the naked eye, Tau is the bottom left star in the tail of Cetus.
Tau is one of the closest stars to our sun at about 12 light years away, or a mere 70 trillion miles. Tau is a middle-aged yellow star like our sun. It is about 90% of the sun’s size but only about 45% of its brightness. In 1959, the astronomers of Project Ozma listened with their radio telescopes for signals from intelligent creatures like us.
If we ever find a way to send probes to other stars, Tau will surely be a prime candidate because of its similarity to our sun. Five planets have been discovered or are suspected. One of them is a “Super-Earth,” 2-6 times the mass of our planet and moored in orbit within the zone that might harbor life.
To the ancients, Cetus represented the fear of the great waters, a vast ocean expanse filled with unknown dangers. When we go out in the cool autumn air to look at Cetus, we should be filled with a different emotion — the glorious promise of new worlds.
Tom Burns is the former director of the Perkins Observatory in Delaware.
