We all miss the sunshine these days when our sun hardly seems to make it over the horizon, and hangs low in the south for the few hours a day it dares to show its face. Its warmth seems feeble and often it does not even dispel the heavy clouds which plague our winter days. Take heart, though, the night sky, when you can see it, is ablaze with the brightest stars of any time of year.
Just after sunset, look towards the southwest low in the sky for the brilliant planet Venus. She is hard to miss, being the most-luminous object in the night sky besides the moon. Watch for her all winter, rising higher and higher in the western sky, and reaching a pinnacle at the end of March. If you have not spotted her yet, be sure to check it out — she is simply dazzling.
Do not stop there, however. As soon as it gets completely dark — which is not very late this time of year — turn your attention to the other direction, the southeast, for the grand display of the brightest stars of the year. The centerpiece of the show is the constellation Orion, probably the most familiar of all the star groupings seen from around the world. In ancient times he was a hunter and a very good one at that, but he was boastful also, a trait not appreciated by the gods. His arrogant bragging was his downfall, but lucky for us, the gods stuck him up in the sky anyway for everyone to enjoy.
Rigel reigns
Orion’s stars are bright, not because they are close, but because they are really bright stars. Take Rigel, for instance. It is found at the lower right hand side of Orion. It shines with a blazing white, almost bluish light, which means it is a young star, bursting with energy, 60,000 times more powerful than our sun. I always think of our little sun as the 98-pound weakling on the beach, but it emits the power of 6 trillion atomic bombs every second, and that is nothing to sneeze at!
If we were to move the earth to an orbit around Rigel, it would have to be five times as far from Rigel as Pluto is from our sun. Otherwise, we would get a scalding sunburn in just a few seconds out under the sun of that powerful star. If the earth were in an orbit that far away, it would take thousands of our years to make one trip around Rigel. That means our year would become thousands of years long. Just imagine how long you would have to wait for Christmas!
Up above Rigel, check out the three stars of Orion’s Belt. There is nothing else in the sky quite like them: three fairly bright stars, evenly spaced and almost in a straight line. All of them are even brighter than Rigel, which means they are farther away.
The light from them has been traveling 2,000 or 3,000 years just to get to your eyeballs. The one on the upper right is actually five stars in one all spinning around each other. The two main stars are so close together they are doing a dance with each other, and it only takes a couple of days to make one gyration around themselves. Each of those two pump out a whopping 90,000 times the brightness of our sun.
Find the middle
Have you ever wondered where the middle of the sky might be? Probably not, but I am going to tell you anyway. That star I was just talking about, the one at the right of Orion’s Belt, which is named Mintaka, by the way, sits almost squarely on the celestial equator, exactly half way between the North Pole and South Pole.
Line up the three stars of the belt and point down and to the left. That will take you to a really bright star, the brightest in the whole night sky, Sirius. So how many thousands of times brighter than our sun does it shine? Actually just a measly 25 times as bright, not thousands at all. You see it is really close to us, in fact it is the closest star besides our sun that we can easily see here from earth. It is only 50 trillion, 740 billion miles from us. That is just a stone’s throw away! If you decide to book a nonstop airline flight there, be sure to pack some snacks and your Kindle. The trip will take about 10 million years!
There are plenty of other bright stars to look at up there, like the orange colored Betelgeuse in Orion, Castor and Pollux of the Gemini twins, or Aldebaran in Taurus, the bull. Have fun under the winter night sky and stay warm!