Messier 13, The Great Globular Cluster in Hercules, is about 145 light-years in diameter, and is composed of several hundred thousand stars, the brightest of which is a red giant. M13 is about 22,200 light-years away from Earth and can be visible to the naked eye depending on circumstances. With a low-power telescope, Messier 13 looks like a comet or fuzzy patch.
Technical info:
TS 80mm f6 APO triplet refractor – ZWO ASI 071 MC Pro + IDAS LPS2 (light pollution) filter
Exposure: 150x 60 sec
Total integration: 2 hrs 30 min
Processed in Astro Pixel Processor and Photoshop CS5