The constellation OrionBy Professor Todd Brown / Contributor

The Orionids meteor shower was the topic last week so it should not be much of a stretch to talk about the host constellation Orion, as it is one of the most recognizable groupings in the sky. Currently rising at midnight, within a few months it will be visible as soon as the sun sets, and make a prominent trek across the night sky of winter.

Orion is familiar to most mainly because it contains so many bright stars in a pattern that almost resembles a human form. If Monet painted stick figures, then Orion would be his masterpiece. Making a list of the Top 35 brightest stars in the night sky, Orion would contain five of them. The brilliantly white Rigel anchors its lower right while the dull red Betelgeuse sits at the top right of Orion’s figure. Respectively, these two are the 7th and 10th brightest stars in the night sky.

More impressive still is that none of its five brightest stars are anywhere close to the sun compared to most visible stars. To be so bright and yet so far away, they must be pumping out enormous amounts of energy (light). If one could place Rigel next to our Sun, the star would outshine our solar system’s star by approximately 50,000 times. Its intense white color portrays a star that is very hot. Its surface temperature is twice that of our suns and it is consuming its fuel with no regard for tomorrow—which, for Rigel, is fine as it has very few “tomorrows” left. Compared to Rigel, as well as our sun, Betelgeuse has a very cool surface. This is why it glows red. But, it is so big that it casts a brilliant light on earth even at its extreme distance. If Betelgeuse could replace our Sun, its disk would not just fill earth’s sky; it would BE earth’s sky. This swollen red supergiant would extend beyond Mars’ position and our planet’s orbit would be well within its boundaries.

Regarding the name of these two bright stars, they are Arabic in origin. At the bottom of Orion we find Rigel, which is aptly means “foot.” Betelgeuse, near the “shoulder” of Orion, translates as “armpit.” I made sure that my two young children, upon getting scrubbed down by me in the bathtub, knew that I always had to wash both of their Betelgeuses. In hindsight, I hope that my eagerness to teach them some astronomy terms will not lead to horrible social problems. I didn’t do anyone any favors when I accidentally taught my daughter to say “galaxy” before she could say “Mommy.”

Orion’s story is varied, as is most mythological tales. One version tells how Orion bragged that he was a great hunter who would rid the world of all wild animals. I suppose that this would lead to a healthier, vegetarian diet but, in the world of Greek gods, it is best to leave well enough alone. In Orion’s case, his boast earned the wrath of Gaea the goddess of the earth who had an understandable fondness for the creatures of the world. I can see the benefits of ridding the world of the 17-Year Cicada or the carnivorous flying attack squirrels of Illinois but I just don’t see the heroism in chasing down all the hamsters of the planet and Gaea seems to have shared my view. She sent an indescribable foe to get Orion: the Scorpion.

Orion tried to best the poisonous arachnid but his sword was no match for its impenetrable armor. Finally, he had to admit defeat, but the Scorpion was not ready to throw in the towel and gave chase. The Scorpion is still in pursuit even to this day. Orion tries to hide in the stars from his nemesis and does this by staying on the opposite side of the sky from the constellation Scorpius (the Scorpion). As the sun sets at this time of year, Scorpius sinks into the west with the fading twilight. Once over the western horizon, the valiant hero Orion sneaks over the eastern horizon, always staying one step ahead of his fate.

What else is out there this week: