M101 is also known as the pinwheel galaxy and NGC-5457, in the constillation Ursa Major was discovered by Pierre Mechain in 1781.
Charles Messier verified the position and added it to his catalog. This galaxy is about 25million light years away. With a diameter of about 170,000 light years, it is about twice the size of our
Milky Way.
The little smudge to the left of M101 is NGC5477. As a member of the M101 group I will assume it is also about 25 million light years away.