O'Ryan the Irish Constellation

© 1987, 2002 by Robert C. Moler

OK, so I'm pulling your leg. There is no O'Ryan. But there is an Orion. Someone once remarked to me that he thought Orion bad something to do with the Irish. So who or what is Orion? Well, first off. he is a hunter.

As a star group Orion is the most famous constellation of the winter sky. At least half of him can be seen all ever the earth from the north pole to the south pole since he straddles the celestial equator. He is seen is an upright rectangle of bright stars. As he rises in December he is tilted to the left. When he is at his peek altitude in the south he Is vertical, and in early spring when he sets his rectangle is tilted to the right. The rectangle represents Orion's torso.

ori-tau.gif (4684 bytes)The bright red star at the upper left is Betelgeuse (usually pronounced beetle-juice or bet-el-gerz). The first pronunciation is more fun, and the one thing we don't have to scrape off the windshield in the winter. The name means either "The Armpit of the White Belted Sheep", or "The Armpit of the Giant". We'd call it the right shoulder of Orion. Betelgeuse is a red super giant star, one of the few that astronomers have actually been able to see the surface. It is a first magnitude star and ranks eleventh In brightness. The upper right star is Bellatrix. "The Amazon Star", a second magnitude star. It marks Orion's other shoulder.

The lower right star is Rigel, a blue giant star and the seventh brightest star in the night sky. Rigel means the "Left Leg of the Giant" and lies In his knee. The other knee star at the lower left corner is Saiph, pronounced safe. It means "The sword of the Powerful One", but is not the sword of Orion that we recognize today.

In the center of the rectangle is a sloping line of three stars, Orion's most distinctive feature, his belt. These three second magnitude stars are, from left to right, Alnitak, Alnilam and Mintika. They mean "Girdle", "Belt of Pearls" and "Belt" respectively. From the belt hanging downward lie what appear to be three fainter stars, though in binoculars each seems at least doubled. The center stars also seem surrounded in a mist. The mist Is the Great Orion Nebula, the brightest diffuse nebula visible from earth.

Upward from Betelgeuse run tan diverging lines of stars that outline Orion's right arm raised holding a club. And right of Bellatrix there is a long and curved line of stars which is his left arm holding a shield made of lion skin.

In Greek mythology Orion is a minor personage. He was indeed a mighty bunter and warrior. He also loved the Goddess Diana a great huntress in her own right. The stories of Orion's demise are a bit conflicting. In one he was killed by accident with one of Diana's arrows. In another story Orion is killed by the sting of a scorpion. It explains as the story goes, why Orion and Scorpius the scorpion are not in the sky at the same time.

Orion's position as the central constellation of the winter sky also leads to stories connecting him with other constellations. Trailing him to the east are his two hunting dogs, Canis Major and Canis Minor. Orion's position with club and shield may be interpreted as warding off the charge of Taurus the Bull to his upper right, while Lepus the hare sits unnoticed at his feet.

Then there is the story of Orion chasing the beautiful daughters of the god Atlas. Zeus, the chief god, solved that problem by placing all of them in the sky, the daughters as the Pleiades to the west of Orion. He still pursues them nightly across the frosty winter sky, but can get no closer.

Getting back to the Irish, the early Irish called this constellation Caomai, the armed king, an image close to the Greek one we accept today. Other cultures saw much the same. There were exceptions. The Chinese saw it as the White Tiger. The Hindus saw it as a stag.

Come to think of it, Orion is about the only thing I like about winter. I love to see it rising in the moonlight above the snow covered landscape. I gaze with fascination at the telescopic wonders it contains, especially the tendrils of luminous gas of the Great Orion Nebula. I mourn its passing into the glare of the spring evening twilight. Even so I hate to see it rise in the morning twilight of August as I often do at the end of the Perseid meteor Shower. It is a grim reminder that summer will soon come to an end. And It does!

Questions? Send Email to me at bob@bjmoler.org

Updated: 01/06/02