Messier 3 is a globular cluster in Canes Venatici lying 33,900 light-years from Earth. It contains about 500,000 stars. It is a Shapley-Sawyer Class VI globular cluster, which implies a core that is resolvable into individual stars. It is one of the most frequently observed globulars in the northern hemisphere, perhaps second only to Messier 13 in Hercules.
Image data:
Telescope/mount: Celestron Compustar C14
Camera: SBIG STL 11000M with Baader Planetarium LRGB filters.
Location: Pommier Observatory, Portland, OR, USA.
Dates: 2018-05-22 through 2021-05-09.
Exposures: L:R:G:B = 85:35:35:30 minutes = 3 hours, 5 minutes total exposure at f/7.5.
See additional astrophotographs at www.rodpommier.com