Globular Clusters
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A globular star cluster is a nearly spherical collection of hundreds of thousands of densly packed stars that are tightly bound together by gravity. Most of the stars in a given cluster were born at the same time, from the same giant molecular cloud, and share a common chemical composition and age. The primary difference between individual stars within the cluster is therefore their mass. These clusters are perhaps the oldest stars in the galaxy, and form an important "laboratory" for the study of stellar evolution. Most globular clusters consist of metal-poor stars (in astronomy, a "metal" is any element heavier than hydrogen and helium), consisting mostly of ancient stars that are 10-12 billion years old. Globular clusters tend to be found in the outer halo of a galaxy, taking a roughly spherical distribution in the Milky Way, where there are approximately 150 known globular clusters.

 

M13 (NGC 6205) in the constellation Hercules	M3 (NGC 5272) in the constellation Canes Venatici
distance: 25,100 light-years	distance: 33,900 light-years
estimated age: ~12 billion years	estimated age: ~11.75-12.5 billion years
apparent diameter: 23 arc-minutes	apparent diameter: 18 arc-minutes
total mass: 5.5 x 105 solar masses	total mass: 4.1 x 105 solar masses
8-inch f/8 RC telescope	8-inch f/8 RC telescope
QHY268M monochrome camera / Astronomik LRGB filters	QHY268M monochrome camera / Astronomik RGB filters
exposure: 3x16x180sec RGB / 32x180sec Luminance	exposure: 3x16x180sec RGB
Processing: Pixinsight-->Photoshop-->Topaz deNoise AI-->Lightroom	Processing: Pixinsight-->Photoshop-->Topaz deNoise AI-->Lightroom

 

M92 (NGC 6341) in the constellation Hercules	TBD
distance: ~27,000 light-years	distance: xx
estimated age: ~11-13.5 billion years	estimated age: xx
apparent diameter: 14 arc-minutes	apparent diameter: xx
total mass: 3.52 x 105 solar masses	total mass: xx
8-inch f/8 RC telescope	xx
QHY268M monochrome camera / Astronomik LRGB filters	xx
exposure: 3x14x180sec RGB / 11x300sec Luminance	xxx
Processing: Pixinsight-->Photoshop-->Lightroom	xx