M101 in Ursa Major is a beautiful, large, face-on spiral galaxy of the type Scd, meaning it has loosely wound spiral arms, clearly resolved into individual stellar clusters and nebulae, and a small, faint central bulge. Like in other large nearby spiral galaxies, several knots of emission nebulosity can be identified in this image. The galaxy is quite near, at a distance of only 21 million light years, and is the center of a small group of galaxies, the M101 Group, with 23 known members, mostly dwarf galaxies. This is a neighbor group to the Local Group of galaxies, of which our Milkyway Galaxy is a member.
If you examine the image above closely, you can spot a few background galaxies. The brightest of these is NGC 5477, an irregular spiral galaxy of the Magellanic type. It can be found not far fron the left edge, above the center.
Exposure Data
