Why so many bright stars

It is always fun to dip into the old mailbag to get a question from readers. This one asks, "Why are there so many bright stars in the winter sky?"

Good question. With the stars of Orion, Auriga, Taurus all hanging just above the eastern horizon after sunset, it would seem there are a lot of bright stars available for our viewing.

There are basically two answers for that question. First, the part of Earth we are standing on in December, January, and February is facing outward away from the center of the Milky Way Galaxy in the evening sky.

That means we are looking outward into the spiral arm near where the Sun is located. It is called the Orion Arm, or more correctly, the Orion Spur.

The second reason is there are not as many stars. The Center of the galaxy -- hich we look at during June, July, and August -- is teeming with stars, thus making the sky brighter and in effect overwhelming some of the stars at which we are looking.

In fact, the star Elnath, is almost directly opposite the galactic center. Where is Elnath?

Go outside at about 7 p.m. local time and find Orion hanging above the southeastern horizon. Above Orion is the "V" shape of Taurus, the Bull.

Follow the line of stars on the upper arm of the "V" to a star on the lower corner of Auriga; that is Elnath. It is shared by both constellations.

Just looking at that group and if you remember our recent discussion of the Winter Circle (or hexagon) we find the stars Rigel, Aldebaran, Castor, Pollux, Procyon, Betelgeuse, and of course, Sirius, the brightest star in the night sky.

Another reason is the center of the galaxy is about 25,000 light-years away, whereas we are located within the Orion Spur. On average the stars in Orion are less than 1,000 light-years. The only one further than that is Alnilam (the center star of the belt) which is 1,350 light-years away.

SKY WATCH: We have been enjoying the long line of morning planets these cold January mornings and now we have one available for viewing in the eastern evening sky. Tonight, Wednesday, Jan. 27, the moon will be floating just below bright Jupiter, both of which will almost be in the same binocular field of view. Be out looking eastward at about 10 p.m. MST.

On Saturday, Jan. 30, the moon has moved on and will be near the bright star Spica in the morning hours. Best time will be between 4 and 5 a.m. MST almost due south.

The moon then moves on to be very near Mars on the morning of Monday, Feb. 1. Best view between 5 a.m. MST and sunrise. Then on Wednesday, Feb. 3, Saturn takes its turn standing next to the moon at about 5 a.m. MST.

That is nice, because the pair will have the center of the galaxy rising behind them with the stars of Sagittarius -- one of the great constellations of summer -- making this a nice place for examination with binoculars.

Sneaking in for a quick appearance on Feb. 2, is Ground Hog Day, one of our Cross-Quarter days marking the approximate halfway point between winter and spring.

So get your umbrellas, find your favorite ground hog hole and make sure that critter does not see its shadow.

NEXT WEEK: More objects to look for and more astronomical blathering.