Known as the "Great Globular Cluster in Hercules", it is one of the best known globular clusters in the northern hemisphere which lies approximately 22,200 ly distant and is roughly 145 ly in diameter. It has a mass of about 6x105 solar masses, contains several hundreds of thousands of stars and is classified, V (intermediate concentrations), on the Shapley-Sawyer globular cluster concentration scale (1927). The edge-on galaxy lower left is NGC 6207 while a fainter galaxy, IC 4617, lies roughly between it and M13.
|Camera:||SBIG STL11000M, Astrodon filters||Scope:||Takahashi TOA-130, f=1000mm, f7.7, fov 1.0° x 0.7°|
|Mount:||Takahashi EM-200 Temma 2||Guiding:||internal|
|Filters/Exposures:||R:G:B = 10:10:10 ≡ 30m||Location:||ASV's LMDSS, Lady's Pass, Victoria, Australia|
|Date:||August 2023||Processing:||CCDStack2, RegiStar and Photoshop CS5|