What a Cluster!

May 10, 2023

From last night's imaging session: the massive star cluster, M13, NGC 6205, the Hercules Globular Cluster, is made up of hundreds of thousands of stars. Like most globular clusters, M13 is not found within the disk and spiral arm structures of the galaxy, but in the galactic halo, the outer spherical shape of the galaxy, above and below the galactic plane. M13 is about 145 lightyears in diameter. Notice the spiral galaxy on the lower left side--that's NGC 6207 (about 30 million lightyears away), with the far more distant galaxy IC 4617 (489 million LY!), just a tiny, faint smear between NGC6207 and the M13 globular cluster. Imaging notes: 800mm f/4 newtonian, ZWO ASI071MC cooled to -10C, 60 x 120-second exposures stacked in DSS.