Archive for January, 2010

The Buzzing Little Bees of M44

Sunday, January 17th, 2010
M44 in Cancer

For the amateur astronomer, few things can match the beauty of a densely packed open cluster. One of my favorites has always been M44, the Beehive Cluster, in Cancer. With it’s brightest star at magnitude 4.2, Cancer is a rather dim constellation and not always obvious to the backyard astronomer, especially when light pollution is an issue. But as can be seen on the map, Cancer is located between the easily found constellations of Leo and Gemini. Also currently passing through that area is Mars. So don’t forget to crank up the magnification and see how much surface detail you can see on the red planet.

Despite being one of the closest star clusters, there is some disagreement about the exact distance to the Beehive Cluster. Current estimates range from about 520 to 610 light years. Being this close means it appears both large and bright (at magnitude 3.1, visible to the naked eye under dark sky conditions.) And so it is best seen with low magnification. A good pair of binoculars would work well, otherwise use the lowest power eyepiece you have.

Are You Sirius?

Saturday, January 2nd, 2010

On these cold winter nights, just a little southeast of Orion, is a dazzlingly bright star – the brightest one in the night sky. Officially called Alpha Canis Majoris (designating it as the brighest star in the constellation Canis Major), it is better known as Sirius or the Dog Star. While the intrinsic luminosity of Sirius is about 25 times that of the sun, much of it’s apparent brightness comes from it’s close proximity to our own solar system. At a distance of 8.6ly, it’s just down the street in interstellar terms.

Although it can’t be seen by the backyard astronomer, Sirius has a small white dwarf compainion star called Sirius B. Due to it’s brightness, Sirius itself often appears to twinkle more than most stars, often flashing a variety of colors. So if you see that bright star in the southern sky this winter, you know it is indeed Sirius.