The stretched celestial dragon
I have mixed feelings about this time of year, with autumn well underway. I really love summer, but every year it seems to go faster and faster. Still, the star-watching nut in me loves this time of year because I can get to my telescope and astronomical camera earlier in the evening, so I don’t have to walk around the next day in a sleep-deprived funk, clutching my deeply charged-up coffee.
Watching the stars on these cooler October evenings is such a relaxing and great way to unwind after a long day. Speaking of unwinding, one of the great constellations has been unwound for a long time. The constellation Draco is supposed to be a Dragon in the sky, but it looks more like a coiled snake because, according to Greek and Roman mythology, Draco got stretched out in the line of duty. I’ll have more on that in just a bit.
Locating Draco the Dragon isn't easy if you’re new to constellation hunting. To quote the great Beatles classic, it takes a long and winding road in the northwestern evening sky. With the help of the bright Summer Triangle and neighboring constellations that it wraps around, you can slay this challenging celestial dragon.
You may want to pull up my October star map from last week’s Starwatch column or go to my website, lynchandthestars.com, as your first step in your heavenly hunt for the great beast. Apps like Sky Guide also help a lot. In a way, Draco resembles a backward “S.” It should be dark enough by around 8 p.m.
Look high in the sky, near the overhead zenith, for the brightest star you can see. That’s Vega, the brightest star in another constellation, Lyra, the Harp, and the brightest star in the famous “Summer Triangle.” From Vega, look about 10 degrees, or the width of your fist held at arm’s length, toward the northern horizon for a small but distinct lopsided diamond of stars that outline Draco’s head.
From Draco’s head, look about 15 degrees to the northeast for two more slightly faint stars. The line from Draco’s head to those two stars makes up the neck of the stretched-out dragon. From there, Draco's body kinks westward in a nearly straight line of brighter stars about 20 degrees long. From there, the dragon's tail kinks into a nearly vertical line northward and ends right between the cup sections of the Big and Little Dippers.
Astronomically, the most significant star in Draco is Thuban, found toward the end of the Dragon’s tail. Thuban was the North Star in our sky around 3000 BC.
Today, Polaris, at the end of the handle of the Little Dipper, is within two degrees of the North Celestial Pole, a projection of Earth’s North Pole onto the sky. In other words, if you were standing at the North Pole, the North Star would be directly over your head. The Earth’s axis has a super slow wobble that takes 26,000 years to complete one cycle. Around 3000 BC, the northern end of Earth’s axis pointed at Thuban. Now it’s directed toward Polaris, and in the year 21,000 AD the Earth’s axis will be pointing at Thuban again … You probably don’t want to wait up for that.
So how did Draco the Dragon wind up unwound in the celestial dome? Well, the story goes like this. Hera, the queen of the gods of Mount Olympus, was given a beautiful set of solid gold apples as a wedding present from her new but far from faithful husband Zeus, the king of the gods. She hoarded her precious apples in her private garden at the castle and had her pet dragon, Draco, guard them.
Those apples were precious to her not so much for their sentimental value as their resale value. Even then, she saw the signs that Zeus was a carousing rat and eventually the royal marriage would fall apart, and when it was all over, the golden apples would still be hers. If you’re hip to Greek and Roman mythology, you know that Hera was no paragon of virtue either. Draco had been Hera’s pet since she was a little goddess girl and was extremely loyal to the little diva. He guarded those apples 24/7 and fended off many dastardly thieves, including Zeus when the marriage collapsed.
Zeus never did get the golden apples back. One lonely moonless night though while Draco was snoozing at his post, Hercules, the legendary Greek hero, smashed the palace gate and leaped toward the golden fruit. Draco rousted himself immediately and a titanic battle broke out that went on for hours. Draco nearly had Hercules trapped in his coiled tail when, with all his might, Hercules pulled a dagger from his shoe and pierced it through the beast’s heart. Hercules then headed off into the night with his plundered golden apples.
Hera discovered Draco’s body and the absent apples. She was greatly upset about losing the golden apples but was more upset about losing a pet she’d known all her life. Hera decided to reward Draco for his loyalty by magically placing his body in the stars as an eternal honor to him. The trouble is that when she picked up his bloody, mangled body and hurled it into the heavens, it quickly and unceremoniously unraveled.
Another legend I love about Draco comes from the early Christian church. They saw the constellation as the snake that tempted Adam and Eve to eat the forbidden fruit in the Garden of Eden. To them, Draco represented original sin.
Again, Draco is not one of the easiest constellations to find, but looking for it and finding it will really sharpen your stargazing skills. Don’t wait too long to try and find it, however, because as we journey farther into autumn it starts out the evening lower and lower in the north northwestern sky until it’s lost in the smudge near the horizon. So, while you can, unwind, relax and capture the dragon!
Big-time celestial happening this week! This will be worth setting your alarm for. Very early Tuesday morning, Oct. 6, the waning crescent Moon will briefly cross in front of the very bright planet Jupiter In the low eastern sky. This kind of eclipse is called an occultation. Depending on exactly where you are, around 4:20 a.m., Jupiter will slip behind the Moon. Around 5:25 a.m., Jupiter will emerge from behind darkened side of the Moon. It’ll be a wonderful sight through even a small telescope or binoculars as the Moon occults Jupiter and its brightest moons!
Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis/St. Paul. He is also the author of “Stars: a Month by Month Tour of the Constellations,” published by Adventure Publications and available at bookstores and at adventurepublications.net. Contact him at mikewlynch@comcast.net.
