Northern sky home to celestial dragon

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Four or five millennia ago, the constellation Draco, the Dragon, was in its prime. Some sort of dragon appears in the myths and legends of every significant ancient civilization. These days, few of us would recognize it if it fell out of the sky and hit us on the noggins.

Draco is easy to find, even though its stars are not exceptionally bright. To see it, go outside just after dark. (“Just after dark” means 11 PM, of course. Curse that curséd Daylight Saving Time.)

Look straight north, about halfway up the sky, and you’ll see Polaris, the North Star. Polaris forms the end of the handle of the Little Dipper, which curves straight upward from Polaris just after dark.

Draco coils above and around the Little Dipper. As a result, the constellation is spread out over a substantial patch of sky. Also, its serpentine curves are a bit more convoluted than most constellations.

Of course, not everybody sees a dragon in Draco’s somewhat chaotic assembly of stars. Ancient Arabic astronomers saw a tableau of creatures they called Mother Camels.

Two of Draco’s stars represent hyenas that are attacking a baby camel. Four female camels, represented by four other stars in the constellation, protect the babe. The nomads who own the camels are oblivious to the threat. A cooking tripod composed of four more stars nearby collectively represents them.

Draco was a significant constellation to the ancients, partly because of a star called Thuban, which the ancient Egyptians fervently worshiped. More on that next week.

Sadly, the star and its parent constellation are nearly invisible from our contemporary, light-polluted skies. Compared to the nearby stars of the Big Dipper, its stars were relatively faint, even to the ancients.

Why was it so important to them? And why isn’t it important now?

The answer lies partly in a couple of constellation stories and a bit of celestial navigation.

The ancient Babylonians recognized it as a dastardly dragon called Tiamat, the symbol of the chaos and disorder that seemed to surround them. Tiamat opposed the gods, controverting their attempts to impose order on the natural world.

He was finally defeated by the sun god Izhdubar, the bringer of light who levied law and order on the world. Izhdubar is represented by the nearby constellation we call Hercules.

In a stupendous battle, Izhdubar drove a great wind into the monster’s open jaws and thus split him in two.

Three millennia later, the ancient Greeks were so fascinated by the constellation that they linked it with two significant characters in their mythological canon.

They associated Draco with the giant dragon Ladon, one of the nasty household pets of Hera, queen of the gods. According to some accounts, Ladon had 100 heads.

Some heads were always awake, so poor Ladon didn’t get much sleep. However, his insomnia made him an excellent watchdog, er, watchdragon.

Ladon’s job was to guard the golden apples that grew on a tree planted in Hera’s garden on the slopes of Mount Atlas. Three beautiful sisters called the Hesperides were initially assigned the job of guarding the apples, but they couldn’t resist picking them.

So Hera added Draco, who coiled himself around the tree. And a worthy guard he was. Each of his 100 heads was deadly.

Along came Hercules, the greatest of the Greek heroes, who was assigned the job of stealing the apples as one of his twelve labors.

He slew the dragon with arrows he had dipped in the poisonous blood of another of Hera’s pets, the Lernean Hydra. He then absconded with the apples.

Soon thereafter, the Hesperides suffered an agonizing death from trying to drink the dragon’s now-poisoned blood.

Hera had many unpleasant qualities, but disloyalty to her beloved pets was not one of them. Because of Ladon’s long service to her, he ended up in the sky as Draco.

Hera loved her pet anyway. To honor his memory, she put him among the stars.

But Draco traces its popularity to a far more practical reason, its prominent placement near Polaris, the North Star.

I’ll have to tell yet another star story to explore the significance of Draco’s lofty placement near the celestial pole. Stay tuned.

Tom Burns is the former director of the Perkins Observatory in Delaware.

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