The Great Nebula in Hercules, M13 contains about 300,000 stars. It is a globular cluster that resides within our own Milky Way Galaxy. M13 is roughly 25,000 light years from Earth. (The Milky Way is somewhat greater than 100,000 light years in diameter.)
This image represents a total exposure time of 4 hours 26 minutes. Each individual exposure was 5 minutes long, using a Canon 6D DSLR camera on my Takahashi Mewlon-250 telescope at f/19.2. The telescope was autoguided. Images were calibrated, aligned and stacked using Deep Sky Stacker 3.3.2. The resulting stacked image was edited using Adobe Photoshop CC.