M101 - The Pinwheel Galaxy in Ursa Major
Copyright 2006 Hap Griffin
One of my favorite astronomical objects...the beautiful Pinwheel Galaxy, known as M101. Recognized as one of the finest examples of a classic spiral, it actually is quite non-symmetrical with its core being considerably off-center. It lies at a distance of 27 million light-years and spans 170,000 light years across its diameter, nearly twice the size of our own Milky-Way galaxy. It has a total luminosity of 30 billion suns.
Note the more distant 15th magnitude spiral galaxy PGC 49919 near the right edge of the frame.
April 1, 2006 Griffin/Hunter
Observatory Bethune, SC
Instrument: Canon 350XT Digital SLR (modified) through 10" Meade RCX400
Focal Ratio: f8
Guiding: Auto through Orion ED-80 w/ SBIG ST-237
Conditions: Visually clear
Weather: 50 deg. F
Exposure: 115 minutes total @ ISO 800 (23 x 5 min exposures)
Filters: Baader UV/IR Block
Processing: Focused and captured with DSLRFocus. Pre-Bayer Interpolation calibrations, frame alignment and stacking, Adaptive Richardson_Lucy deconvolution, scaling and JPEG conversion with ImagesPlus. Color correction, curves and levels with Photoshop 6. Noise reduction with NeatImage.