Whirlpool Galaxy M51 - DSLR
The "Whirlpool Galaxy," termed M51 for the 51st object in the Messier catalog, was discovered by Charles Messier in 1772.  The attached image shows the both the spiral galaxy and
its smaller irregular companion galaxy.  The interaction between the two galaxies is stretching one of the spiral arms of the Whirlpool.  M51 has been estimated to contain 60 billion
solar masses.  The light reaching my camera originated from the galaxies 15 million years ago.

The image above was obtained with a Canon 60Da camera, through a TEC 140mm refractor, mounted on an AP900 GTO.  I combined ten 5-minute exposures for a total exposure
time of 50 minutes.  This wide field view shows two distant edge-on spiral galaxies in the upper right and elliptical galaxies in the lower right and upper right edge.

The image below was obtained an a crisp cold winter night between 1 and 5 a.m., when the air was unusually steady, allowing a high resolution image.  I only needed 90 minutes of
luminance exposures blended with 30 minutes each of red, green, and blue exposures to yield this result.  Source images were 5 minute exposures, unbinned for luminance and binned
2x2 for color.  I used an ST10XME camera, Astro-physics nosepiece reducer, through a 12" Meade RC/SCT, at the dark skies of the Hidden Lake Observatory.  Oh, what a night!
Music:  Oh, What a Night
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