The Great Globular Cluster in Hercules

This is one of the very first deep space objects I ever saw with my first telescope. It’s one of the biggest and brightest globular clusters in the sky and easily the brightest that can be seen at my latitude. Globular clusters are kind of neat, but kind of boring at the same time. At first glance, they all pretty much look alike. It’s a round glob of hundreds of thousands of stars. What makes these neat is because there are so many stars in a small space, astronomers can use these to study stellar evolution. While most of the stars in globulars are old, new stars forum there as well.

The fact these clusters are made up of mostly old stars brought up an interesting struggle while I was processing this photo. You’ll see other photos show mostly blue stars in a cluster. While the blue is very pretty, it isn’t very accurate. Stars are almost perfect black bodies when it comes to Kirchhoff’s law of thermal radiation, things that burn very hot emit in the blue spectrum. As the temperature goes down, the light shifts to the red side of the spectrum. This is how one can tell how hot a star is based on its color. There is also a correlation between the age of a star and hot or cool it burns.

This was taken from my very light polluted backyard with my ASI1600MM-Cool, 8in RC w/ CCDT67 reducer, Astrodon RGB filters (No Lum used), all riding on my AP Mach1GTO4.