Posted by Kelly on December 30th, 2013
In a large portion of the world, stargazing in December, January, and February is not ideal. As I write this it is -11 degrees Fahrenheit or -24 Celsius. I’m also battling with some sort of sinus illness that is starting to feel reminiscent of the plague, which only makes me want to stay indoors all the more.
But the thing about winter’s sky is that some of the brightest stars reside there. You can spot them from inside your warm home. Turn off all the lights (except for the orange glow coming off the fireplace) and peer outside at the southeastern night sky. It’s easy to spot the six stars that make up the Winter Hexagon. This season Jupiter is near the middle of them, making this region of sky an even bigger draw. Of these six stars, two are also part of the Winter Triangle along with one other star that is near the center of the Winter Hexagon. These seven stars are some of the brightest in the sky.
Starting with the brightest, the stars are
• Sirius, 1st brightest star, in Canis Major
• Capella, 6th brightest star, in Auriga
• Rigel, 7th brightest star in Orion
• Procyon, 8th brightest star, in Canis Minor
• Betelgeuse, 10th brightest star, in Orion
• Aldebaran, 14th brightest star, in Taurus
• Pollux, 17th brightest star, in Gemini
The stars above, minus Betelgeuse, form the Winter Hexagon, and Betelgeuse (the bright shoulder star of Orion) plus Sirius and Procyon form the Winter Triangle.
The stars of the Winter Hexagon rise above the eastern horizon by mid-evening in winter. The first star to appear is magnitude 0.08 Capella in Auriga, followed by magnitude 0.87 Aldebaran in Taurus. The next three stars all rise above the horizon at about the same time: Pollux, Betelgeuse, and Rigel. Pollux, at magnitude 1.15, marks one of the heads of the twins of Gemini. Castor, the other head, is just a bit dimmer and rises before Pollux. Gemini and its stars rise north of east. Betelgeuse and Rigel are both part of the constellation Orion, which looks as if it is emerging out of the ground on its side as it takes to the sky. Betelgeuse, at magnitude 0.45, marks one of Orion the Hunter’s shoulders, and Rigel, at magnitude 0.18, marks the knee on the opposite side of Orion’s body. Betelgeuse is located near the center of the Hexagon and is the first star of the Winter Triangle to rise. The last two stars in the Hexagon and the Winter Triangle are Procyon of Canis Minor the Little Dog and Sirius of Canis Major the Great Dog. Procyon, at magnitude 0.40, has a name that means “before the dog.” Sirius, the brightest star in the sky at magnitude -1.44, is a bit farther south than Procyon. Sirius is sometimes called the Dog Star.
If you are braver than I am (or someplace warmer), you can get out your telescope and spot much of interest inside the Winter Hexagon. Star clusters and nebulas can be found here, including the Crab Nebula, the Orion Nebula, the Rosette Nebula, the Christmas Tree Cluster, the Hyades Cluster, and much more. For those who live in Florida and southward, another bright star hangs below the Winter Hexagon: Canopus. Canopus is in the constellation Carina and is the second brightest star in the sky.