Cookie consent

AstroBin saves small pieces of text information (cookies) on your device in order to deliver better content and for statistical purposes. You can disable the usage of cookies by changing the settings of your browser. By browsing AstroBin without changing the browser settings, you grant us permission to store that information on your device.

I agree
Contains:  NGC 5477, M 101, NGC 5457
Getting plate-solving status, please wait...
M101 - The Pinwheel Galaxy, 


            David Schlaudt
M101 - The Pinwheel Galaxy

M101 - The Pinwheel Galaxy

Technical card

Resolution: 8350x6680

Dates:April 26, 2019

ZWO B 1.25" optimized for ASI1600: 65x180" (gain: 300.00) -20C bin 1x1
ZWO G 1.25" optimized for ASI1600: 65x180" (gain: 300.00) -20C bin 1x1
ZWO Hɑ 7nm 1.25": 20x180" (gain: 300.00) -20C bin 1x1
ZWO L 1.25" optimized for ASI1600: 65x180" (gain: 300.00) -20C bin 1x1
ZWO R 1.25" optimized for ASI1600: 65x180" (gain: 300.00) -20C bin 1x1

Integration: 14.0 hours

Darks: ~10

Flats: ~20

Avg. Moon age: 21.75 days

Avg. Moon phase: 54.18%

Bortle Dark-Sky Scale: 4.00 job: 2673107

RA center: 14h 3' 12"

DEC center: +54° 20' 45"

Pixel scale: 0.344 arcsec/pixel

Orientation: 76.768 degrees

Field radius: 0.511

Locations: Home, Rockford, Michigan, United States

Data source: Backyard


M101, aka the Pinwheel Galaxy, was my project for the month of April. The resulting image is a combination of data captured over the course of 5 different nights in the past month and is to date the longest total integration time I’ve captured for any single object.

Galaxies are probably my favorite objects to image, it will never cease to amaze me the scale of what I’m looking at when I first see the object show up on the screen. M101 is a large spiral galaxy with an approximate diameter of 170,000 light-years. At 25 million light years away it is actually relatively close compared to many other large galaxies. One of the things that makes M101 unique to observe is that it is a “face-on” spiral galaxy, meaning from our vantage point we’re looking at the “top” of the galaxy. This allows us to see in awesome detail the structure of the spiral arms which give the object its name, the Pinwheel Galaxy. As with most galaxies M101 is best imaged using broadband filters (LRGB), however, as I’ve done with other galaxies recently, I’ve integrated some Ha narrowband data into the image to highlight the many star forming nebulas located along the galaxies spiral arms.



David Schlaudt
License: Attribution Creative Commons

Sky plot

Sky plot


M101 - The Pinwheel Galaxy, 


            David Schlaudt