Messier 101 Or Pinwheel Galaxy In The Constellation Ursa Major Taken With CCD Camera And Medium Focal Length Telescope Stock Image

The Pinwheel Galaxy (Messier 101, M101 or NGC 5457) is a face-on spiral galaxy distanced 21 million light-years away in the constellation Ursa Major. M101 is a large galaxy with a diameter of 170,000 light-years. It has a disk mass on the order of 100 billion solar masses, along with a small central bulge of about 3 billion solar masses. Its apparent dimension is 28.8' × 26.9', very large, nearly the size of the full moon.