M 101

M101 is a large galaxy (170 000 light years across) and takes up a large area of sky (almost half a degree in diameter). In long exposure photographs, it is a striking face on spiral galaxy. Visually, however, it is difficult to observe detail due to its low surface brightness. It is rather easy to locate as it lies close to the naked eye double star Mizar/Alcor in Ursa Major. The galaxy�s diffuse glow can be spotted in binoculars, but a telescope and dark skies are needed to get a glimpse of the galaxies faint spiral arms. Use low to moderate magnification to detect subtle detail. M101 is the brightest of a group that contains at least 9 galaxies.