Located in the direction of Ophiuchus, it is roughly 21,500 ly distant and about 100 ly across. Having a mass of about 1.2x106 solar masses, it is among the ten most massive and luminous globular clusters in our galaxy. Relatively metal-poor (ie contains few elements heavier than helium), its metals abundance is suggestive of two phases of star formation. Classified, IV (intermediate rich concentrations), on the Shapley-Sawyer globular cluster concentration scale (1927).
|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:||July 2023||Processing:||CCDStack2, RegiStar and Photoshop CS5|