M13 (aka NGC 6205, or the Hercules Globular Cluster), is a globular cluster in the constellation of Hercules. About 145 light-years in diameter, M13 is composed of several hundred thousand stars, the brightest of which is a red giant, the variable star V11, also known as V1554 Herculis. M13 is about 25.000 light-years away from Earth, and the globular cluster is one of over one hundred clusters that orbit the center of the Milky Way.
Globular Cluster M13, Vorst (D), 22 April 2020, William Optics 110 mm APO FLT f/7, Canon EOS 600D, UV-IR, UHC filter, 800 ISO, f = 770 mm, 3720 sec, PixInsight V 1.8.8-5
.