You would think I’d know better by now. For 50 springs, I have stood under the starry sky this time of year and looked at the mighty hunter Orion as it slowly sinks to the southwest. What in heaven’s name is a winter constellation doing up so high as spring begins to rear its glorious head? But there he is with his two loyal hunting dogs following him across the sky.
That’s right. Dogs. Plural. Any self-respecting hunter has at least two huntin’ dawgs. As I hiked the trails of West Virginia, I saw bear hunters preceded by entire packs of fearsome pooches. Orion, a manly man of great manliness, is no exception.
Canis Major (the “Greater Dog”) stands below and to the left of his master. You can’t miss old Major. The three bright stars in Orion’s belt point to the left to find the brightest star in the night, Sirius, the Dog Star, which represents the head of the Greater Dog.
Wedged to the right of the dog and below the hunter is Lepus, the Hare. Canis is presumably drawing a bead on the hare as it cowers at the feet of the mighty hunter.
To the right of Orion is another, far-more-formidable example of the Hunter’s prey. Look for the V-shaped head of Taurus, the Bull, setting in the west. It’s hard to miss Taurus because of his bright bloodshot eye, the orange-red star Aldebaran.
Orion has an emergency backup dog, Canis Minor (the “Lesser Dog”), which is far to his left and far harder to find than other constellations in the group. Its only bright star is Procyon, which means “before the dog” in Greek. The name indicates that, like most small dogs of my acquaintance, Minor is a touch hyperactive. Rising above the horizon just before the Greater Dog, it scoots ahead of Major.
You couldn’t ask for more faithful companions. For as long as humans have looked upward, Major and Minor have followed Orion as they chase the Bull again and again across the face of the night.
Canis Major doesn’t have to worry about playing second fiddle to Orion. His head, Sirius, outshines all the other stars in the nighttime sky.
Let’s find Canis Major and its brightest star. First, find Orion, which is getting low in the southwest just after dark. At the center of Orion is a bright, almost horizontal, line of stars that form his belt. The belt stars point toward the south to a very bright star that will be close to the horizon. You’ve just found Canis Major’s head.
The dog’s “ears” are stars found directly to the right and left. The star to the right, Mirzam, is called “The Announcer” because it rises just before Sirius and announces its arrival.
Because Sirius is so bright, it scintillates and twinkles like crazy when it is close to the horizon. Such twinkling is caused by turbulence in Earth’s atmosphere. Often Sirius seems to change color and even disappear as the thick layer of the atmosphere near the horizon moves the star’s light around and makes it dance.
Sirius is relatively close to our sun as stars go at about nine light-years or approximately 50 trillion miles. To give you an idea of how far away the stars in our galaxy are, even though Sirius is only the fifth closest star to our solar system, it is still over half a million times farther away than our Earth is from the sun. It’s a long trip to the neighbors in the vastness of the cosmos.
Sirius is only twice the sun’s diameter and mass, yet it shines with over twenty times the sun’s brightness.
The ancient Egyptians called Sirius “The Nile Star” because the River Nile flooded about the time that Sirius rose just before dawn at the end of June.
With the subsequent flood came the rich Nile soil, upon which the Egyptians depended for their crops. The Nile flooding meant life to the people of Egypt, and the star heralded their good fortune.
Just below Sirius in the sky is a faint, hazy patch just visible to the naked eye if you aren’t observing too close to the streetlights of Columbus. In a set of binoculars, this faint patch resolves into a beautiful, course cluster of about a dozen stars, marked as M41 on most star maps. I’ve always thought of it as Canis Major’s license tag, hanging as it does just below his neck.
Sirius served as a kind of rough weather forecaster for the ancients. During the coldest time of the year, it has always risen at sunset.
During the sweltering heat of late summer, Sirius rises with the sun. The ancients believed that its brilliance added to the sun’s heat, producing what we still call the “dog days” of summer. In fact, the name Sirius means “the scorching one.”
As a result, the ancient Greeks and Romans feared the daytime rising of Canis Major. It meant for them the drought and possible famine that came with the scorching heat of the late summer. As Virgil writes in the Aeneid, it was believed to be the “burning constellation” that “brings drought and diseases on sickly mortals, rises and saddens the sky with inauspicious light.”
No story that I know of explains how Orion got his dogs. In fact, ancient myths associate them with different owners.
Canis Major is sometimes called Laelaps, a dog so fleet of foot that no prey could escape it. In one story, the dog and a javelin were presented to Procris, daughter of the king of Athens and wife of the hunter Cephalus.
The javelin was magical. Its bearer could never miss, which turned out to be bad luck for Procris. She and her husband were hunting one day when Cephalus accidentally ran her through.
Consequently, Cephalus inherited the dog. As Greek heroes often did, they subsequently wandered the Earth in quest of adventures that would somehow assuage their grief.
They ended up a small Grecian town called Thebes, where a nasty fox was raiding the local hen houses.
Cephalus decided to do his good deed for the decade and set the dog loose to catch the fox.
There was one small problem — the fox was so fast that nothing could catch it.
Here we have one of those logical conundrums that the Greeks were so fond of — a dog that could catch any animal and an animal that could never be caught.
Something had to be done, or the logic textbooks would all have to be rewritten. So Zeus, the head honcho on mount Olympus, turned the fox and dog into stone. The dog he placed in the night sky to honor his swiftness. The fox became a lawn decoration, I guess, because no such ancient constellation exists.
The Lesser Dog, meantime, represents Maera, one of Icarus’s canine companions. Icarus was the first human to learn to make wine. He got some shepherds drunk, and in gratitude, they killed him on the spot. (If you must drink, please don’t drink and herd sheep.) In Lassie-like fashion, Maera ran to get help. He dragged Icarus’s daughter Erigone to the scene, where, grief-stricken, they committed suicide.
Just how a dog can take its own life is lost in the inky depths of history. In any case, the gods put the Lesser Dog in the sky to honor its loyalty. We see it to this day, its head up, howling with pain at the loss of its master.
Ah, another inspiring tale of yore. It takes all kinds to make a universe, I suppose.
Tom Burns is the former director of the Perkins Observatory in Delaware.