Messier 101, the Pinwheel Galaxy   HOME INDEX BACK NEXT

Spiral galaxy in Ursa Major

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Just a few degrees above the end of the Big Dipper's handle is the Pinwheel Galaxy, a fine example of a face-on spiral galaxy of type Sc. In Edwin Hubble's classification scheme, spiral galaxies are divided into three main types, Sa, Sb, and Sc, with type Sc galaxies having the loosest arm structures and the smallest nuclear regions compared to the overall diameter of the arms. The galaxy is about 21 million light years away.

Through a medium-sized telescope, this galaxy appears as a faint circular glow with a bright center. With my 18-inch Dobsonian, the spiral arms and several bright knots within them can be seen, making this object an impressive sight.

Magnitude 7.7
Apparent Size 27' x 26'
Distance (light yrs) 21 million
Right Ascension 14:03.2
Declination +60 42

Image details:  Exposure times of 54 minutes luminance, 24 minutes red, 24 minutes green, and 22 minutes blue, taken with an SBIG ST-8300M imager and a 14" Meade LX850 telescope at f/6.

June 2014