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M101 – Pinwheel Galaxy

The Pinwheel Galaxy (M101) is a striking face-on spiral galaxy in the constellation Ursa Major.  It can be located with your telescope by star-hopping from the bright star, Alkaid, in the handle of the Big Dipper.

M101 - Pinwheel Galaxy

The Pinwheel Galaxy through an 80mm telescope

The image above was captured from my dark sky site, about 40 minutes from home.  The skies are much darker there, a blue zone on the light pollution map, as opposed to red at home.

M101 – The Pinwheel Galaxy

The Pinwheel Galaxy appears quite small in my 80mm apochromatic refractor (480mm focal length).  The field of view is very wide and collects light from several surrounding, smaller galaxies.

Free Shipping with Select Dobsonian Telescopes!I tend to spend time on this particular deep-sky object during Early spring, as this is when it’s location is the most convenient for tracking.   In mid-April, M101 rises high into the Northeast, swinging around the Polaris and the North celestial pole.

Messier 101 lies about 25 million light-years from Earth, and is measured at an enormous 170,000 light across!  This massive galaxy is almost twice the size of our own Milky Way galaxy.

No matter what size of telescope you use, the Pinwheel Galaxy is worth a look both visually and with your digital camera.

Astrophotography Processing Notes:

As is the case when processing all small galaxy images, a large emphasis is given to the color and balance of the background space.  For my image, several iterations of gradient removal and noise reduction were applied.  A layer mask was used to protect the Pinwheel Galaxy structure from losing detail and color.

The star size was reduced a great detail from the original file, to boost the contrast and depth of the image.  All of the software I used to process this astrophoto can be found in the resources section of this website.

Image Details:

Photographed on: April 18, 2015

Telescope: Explore Scientific ED80 with WO Flat III 0.8x FR/FF
Mount: Sky Watcher HEQ-5 Pro Synscan
Guiding: Meade DSI Pro II and PHD Guiding
Guide Scope: Orion Mini 50mm
Camera: Canon EOS 450D (Modified)
Processing Software: Deep Sky Stacker, Photoshop CC

Guided with PHD Guiding
Stacked in Deep Sky Stacker
Processed in Adobe Photoshop CC

The Pinwheel Galaxy was the subject of one of my astrophotography videos in April of 2017:

The photo above was data captured previously to what was captured in the video.  The images captured on April 8, 2017, were of limited value due to the conditions they were shot in (nearly full moon).

The Pinwheel Galaxy – Star Chart

Find M101 in the big dipper constellation



Image Processing Tips: Remove Gradients in Photoshop

8 Deep-SKy Targets for Galaxy Season

Wide Field Astrophotography Telescope: Explore Scientific ED80 Review

Light Pollution Map