A NOTE ABOUT LATITUDE: These sky charts assume an observer at 40 degrees north latitude; much of the world's population lives within 20 degrees or so of 40 degrees north, so it is a useful latitude assumption. However, if you are north of this latitude, the stars will all appear shifted towards the south; if you reside south of this latitude, the stars will appear shifted to the north.
Northern Hemisphere winters provide a treasure trove of not only long nights with dark skies, but bright stars that populate the heavens too. It may seem like the stars are brighter simply because the air is drier during the winter months, but the fact is, there really ARE a lot more stars that are brighter! First, watch this video (COMING SOON) on how to measure distance in the sky. And if you are unsure about the differences in magnitude, check out this video (COMING SOON) first as well.
During winter, in the southern and western part of the sky, you should see a lot of bright stars. Perhaps the most obvious is Orion, with for bright star forming a quadrangle around three 2-nd magnitude stars nearly in a straight line. This is Orion the Hunter; to the upper left if the bright star Betelgeuse, which looks slightly orange, and to the lower right is a bluish-white star; this is Rigel. In-between these, Orion's three belt stars are difficult to miss, as they are similar in brightness to each other, and just three degrees across. If we go down and to the left of these “belt” stars about 20 degrees, we will find the brightest star in the sky, Sirius. This star is the lead star of Canis Major, the Big Dog of Orion. To the east and above Sirius at this time of year is another 1-st magnitude star, Procyon of Canis Minor. There are just two stars that really make up this small, unremarkable constellation.
Back to Orion: Looking at his belt again, go up and to the right about 20 degrees. This will put you at Aldebaran, the “eye” of Taurus the Bull, around which is the large open cluster of the Hyades. Continuing on 15 degrees in the same direction, you may even spot the Pleiades, a smaller open cluster that many people confuse as being the Little Dipper, with 5 stars appearing like a tiny dipper, but don't be confused!
Towards overhead, you can't miss Capella, the brightest star in the pentagon shaped Auriga the Charioteer. And remember where Procyon is? Now look above a line across these stars, about halfway between them: You should see the “twins” of Castor and Pollux in Gemini. You can draw a very large hexagon from Capella, to Castor/Pollux, then to Procyon, Sirius, over to Rigel at the lower/right corner of Orion, and back up to Aldebaran in Taurus. This is known as the “Winter Circle” or “Winter Hexagon.”
From the “Castor/Pollux” section of Gemini going up through the bright Capella, we extend out another 20 degrees and find Mirfak, the 2nd magnitude heart of Perseus the hero. Not far beyond the constellation and setting towards the west are Andromeda the Princess and Pegasus the winged horse. The northern section of the sky is largely devoid of bright stars, save for the “W” shape of the queen in the northwestern sky. This is Cassiopeia, the queen, and her king-husband Cepheus is just a short hop away, by following a line from Alpha Cassiopeiae through Beta Cassiopeiae. The “king” looks a bit like a house shape at this time of year, and despite having the Milky Way running right through it, most of the stars in Cepheus are dim.
To the east, there are spring constellations and stars rising that may be visible, such as Leo, Virgo and Arcturus, among others. Click ahead to see the Spring Constellations page, as these constellations will be visible later at night during the spring months.
But that should help you find your way around the winter sky – give it a try on a clear night, and if you want to see more, look for the star charts at this site for deep sky objects you may be able to spot in the winter sky as well.