Archive for May, 2010

Coma Star Cluster

Friday, May 14th, 2010

When we think of astronomy, we usually think of peering through a telescope at some faint fuzzy out in deep space. But the good news for beginners who may not own a telescope is that some deep sky objects are best seen through a pair of binoculars (which really are just a pair of small telescopes anyway.) One such object is the Coma Star Cluster (officially known as Melotte 111) in Coma Berenices. At a distance of 288 light-years, this open cluster is close enough to cover more than five degrees of sky. With only about 40 stars, it’s not one of the more densely packed clusters. But the good news is that a dozen or so of the stars are bright enough to be seen even from light polluted areas.

Finding the Coma Star Cluster is easy as it lies almost halfway between two bright stars. Start with Denebola, the bright star at the “tail” of Leo, and look toward Cor Caroli. The Coma Star Cluster will be right in between. If you’re not sure which star is Cor Caroli, look toward the end of the Big Dipper’s handle when moving away from Denebola. Cor Caroli will be about two thirds of the way to Alkaid, the star at the end of the handle.

M5 in Serpens Caput

Monday, May 3rd, 2010

Globular clusters can be among the most beautiful objects in the night sky, and I rarely miss the chance to see one. Well situated for viewing this time of year is M5 in Serpens Caput. With a diameter of roughly 165 light-years, M5 is one of the larger known globular clusters. And at magnitude 5.8, it’s also bright enough to show some nice detail.

Bright Arcturus is a good starting spot for a star-hop to M5. Imagine a line to the southeast to delta Ophiuchus. A little to the side of that line will be alpha Serpens. At around magnitude 2.7, both of these stars are much dimmer than Arcturus,  but are still bright enough to be easily found. M5 can be found roughly across the line from alpha Serpens. It’s not one of  the more exact star-hops, but it doesn’t need to be. Once you’re in the area, M5 should show up nicely in your finder scope, giving you the chance to enjoy this bit of deep sky beauty.