M101, The Pinwheel Galaxy

The Pinwheel is a spiral galaxy in Ursa Major, also in this photograph is NGC 5474, another galaxy, which is the fuzzy blob at the 3 o'clock position.

M101 has an apparent magnitude of 8.2, if this was a star, I would have no trouble spotting it through my small refractor. However, this is a face on spiral and I had to convince myself that I could actually see it in the eyepiece.

The Pinwheel M101, also known as Arp 26, has blue spiral arms teeming with young stars, and is asymmetric in shape, both are indicative of an interaction with another galaxy, sometime in the past few million years.

I affixed my DSLR to the telescope, set the gain to 1600 ISO and gave a 60 second exposure, which magically revealed the faint fuzzy that proved to be M101.

After that initial image, I adjusted the shutter duration to 120 seconds, and after every 10 exposures, I made 5 Dark frames.



80 mm refractor, 3 1/2" extension tube, Astronomik CLS filter and a standard Canon 10D DSLR.
50 x 120 sub-exposures at 1600 ISO, stacked in Nebulosity and finished in Photoshop CS3.