A Spiral Galaxy, Bar None! M109 in Ursa Major
Copyright Howard Trottier
I shot the raw frames for this image of Messier 109 last month, for three consecutive nights, April 20-22 2012, from my Cabin in the Sky Observatory
. I used my PlaneWave CDK17, operating with a focal reducer at f/4.5, and riding on a Paramount ME, along with an SBIG STL-4020M camera.
This was my first chance to use my gear since last September, having been frustrated by work, weather, and Moon all this time. This is galaxy season, and I went after M109 because of the big bar that anchors its spiral arms! Is this the best of the barred spirals, for both brightness and the prominence of the bar? Either way, it's a fascinating object.
This is the result of 8 hours of exposure: 240 minutes in luminance (unbinned), and 80 minutes in each of red, green, and blue filters (all binned 2x2). Ten minute subframes were taken in all channels. I actually took just under 12 hours, but intermittent cloud was a bit of a spoiler, and I tossed 4 hours worth. Image capture was done with TheSkyX, MaxIm DL, and FocusMax. Image processing was done with PixInsight and CCDInspector. The field of view is about 27' on a side, and the unbinned pixel size is about 0.78".
Thanks for looking!