M-54 (NGC-6715) A globular star cluster located in the constellation of Sagittarius, approximately 1.5 degrees WSW of Zeta Sagittarii. It was discovered by Charles Messier in 1778, and added to his catalog as number 54. It lies at a distance of 50,000 light years from Earth and is 300 light years in diameter. It is located in a dense starfield. Its core is suspected of harboring an intermediate mass black hole.
This image, acquired on June 22, 2012, is a 20 minute integration of 40 second exposures through the Celestron C-11 at f/2 using the HyperStar III imaging system and the Starlight Express SXVR-H694C color CCD camera, operating at -10 degrees below ambient temperature and bined 1 X 1. Guided, captured and combined using Maxim DL5 Pro. Post processed using PhotoShop CS2, Gradient XTerminator, StarShrink, Carboni's Astro Tools and NoiseWare.