Messier 101 (M 101)

Introduction | Map | My Best Own Photos | My Own Observations | References || Appendix: My Own Photos

On this page I collect my observations of the spiral galaxy M 101 (Pinwheel Galaxy; NGC 5457) in the constellation Ursa Major.

Introduction

The spiral galaxy M 101 (Pinwheel Galaxy) in the constellation Ursa Major is seen face-on, similar to M 99 and M 100, but much larger than both; it is quite impressive in the eVscope. In the Vespera, you can also see the dwarf galaxies NGC 5474 (spiral) and NGC 5477 (irregular) (but not at the same time in the normal FOV). In the Vespera Pro you can see even more galaxies (NGC 5422, NGC 5473, NGC 5474, NGC 5477, NGC 5484, NGC 5485), depending on the section.

A new supernova SN 2023ixf was discovered in M 101 on May 19, 2023; I photographed it on June 2, 2023 with the Vespera.

M 101 (Pinwheel Galaxy; NGC 5457)	NGC 5474	NGC 5477
Size: 28.8'× 26.9' (Wikipedia) Distance: 21.6 million light years (Wikipedia) Rating: ** (Stoyan) Type: Spiral	Size: 4.7' x 4.7' (Wikipedia) Distance: 17 million light years (Wikipedia) Rating: --- Type: Spiral	Size: 1.6' x 1.3' (Wikipedia) Distance: 19 million light years (Wikipedia) Rating: --- Type: irregular

NGC 5422	NGC 5473	NGC 5484	NGC 5485
Size: 3.9' × 0.7' (Wikipedia) Distance: 87 million light years (Wikipedia) Rating: --- Type: Lenticular	Size: 2.2'× 1.7' (Wikipedia) Distance: 96 million light years (Wikipedia) Rating: --- Type: Lenticular	Size: 0.8' × 0.7' (Wikipedia) Distance: 96 million light years (Wikipedia) Rating: --- Type: Elliptical	Size: 2.3' × 1.9' (Wikipedia) Distance: 92 million light years (Wikipedia) Rating: --- Type: Lenticular

H II Regions

M 101 contains a number of H II regions. For more information see page Vaonis Vespera - H II Regions. Only the evaluation by nova.astrometry.net is shown here (M 101, June 2, 2023):

H II regions in M 101: NGC 5447/50, NGC 5449, NGC 5451, NGC 5453, NGC 5455, NGC 5458, NGC 5461, NGC 5462, NGC 5471 (dwarf galaxy NGC 5477 to the right)

Map

The spiral galaxy M 101 (Pinwheel Galaxy) in the constellation Ursa Major (Image Courtesy of SkySafari Astronomy, www.simulationcurriculum.com)

My Best Own Photos

eVscope


M 101 - Jun 11, 2020	M 101 - Sep 8, 2020	M 101 - Sep 8, 2020

M 101 - Jun 11, 2020, photo on top processed	M 101 - Sep 8, 2020, photo on top processed	M 101 - Sep 8, 2020, photo on top processed

M 101 - Mar 6, 2021	M 101 - Mar 6, 2021	M 101 - May 30, 2021

M 101 - Mar 6, 2021, photo on top processed	M 101 - Mar 6, 2021, photo on top processed	M 101 - May 30, 2021, photo on top processed

eVscope 2 (3)


M 101 - Aug 22, 2022	M 101 - Aug 21, 2023, 10 min	M 101 - Aug 25, 2023, 32 min

M 101 - Aug 22, 2022, photo on top processed	M 101 - Aug 21, 2023, photo on top processed	M 101 - Aug 25, 2023, photo on top processed

Vespera


M 101, Jul 29, 2022 - original (82 frames = 820 seconds); dwarf galaxy NGC 5474 to the left		M 101, Aug 7, 2022 - original (191 frames = 1910 seconds); dwarf galaxy NGC 5474 to the left

M 101, Jun 2, 2023 - original (186 frames = 1860 seconds)		M 101, Jun 2, 2023 - original (186 frames = 1860 seconds); supernova SN 2023ixf marked (red dot)

Vespera Pro


M 101, Mar 27, 2025 - 2000p (540 frames = 90 min)		M 101, Mar 27, 2025 - 2000p (540 frames = 90 min), processed

M 101, Mar 27, 2025 - 2000p (540 frames = 90 min), processed and denoised (PAI)		Evaluation with nova.astrometry.net

M 101, Mar 27, 2025 - 2000p (540 frames = 90 min), processed from TIFF and denoised (PAI)		M 101, Mar 27, 2025 - 2000p (540 frames = 90 min), 1:1 section, processed from TIFF and denoised (PAI)

Further NGC galaxies: NGC 5422, NGC 5473, NGC 5474, NGC 5477; for the HII regions within M 101 see page H II Regions.

My Own Observations

Observations March to September 2020

March 15, 23, and 25, 2020 (Mühlhausen/Kraichgau: eVscope): M 101 photographed; best and great on March 25.
April 19, 2020 (Mühlhausen/Kraichgau: eVscope): M 101 photographed, somewhat fuzzy.
April 21, 2020 (Mühlhausen/Kraichgau: eVscope): M 101 photographed.
April 22, 2020 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (no overlay, rectangular format)
May 5, 2020 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (n.o., r.f.); nearly full moon.
June 11, 2020 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (n.o., r.f.)
June 12, 2020 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (n.o., r.f.)
July 3, 2020 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (n.o., r.f.), sky too bright
July 9, 2020 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (n.o., r.f.), partly poor conditions
August 8, 2020 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (n.o., r.f.), poor conditions
August 19, 2020 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (n.o., r.f.), poor conditions
September 8, 2020 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (n.o., r.f.)

Observations March to May 2021

March 6, 2021 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (n.o., r.f.)
May 30, 2021 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (n.o., r.f.), new image size and processing.

Observations July to September 2021

July 18, 2021 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (n.o., r.f.), new image size and processing, poor collimation despite new collimation
July 29, 2021 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (n.o., r.f.), new image size and processing, poor collimation, exposed too shortly
August 20, 2021 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (n.o., r.f.), new image size and processing, better new collimation, poor...
September 8, 2021 (Mühlhausen/Kraichgau: eVscope): M 101 photographed (n.o., r.f.), new image size and processing; exposed too shortly...

Observations April 2022

April 9, 2022 (Mühlhausen/Kraichgau: eVscope 2): M 101 photographed (app version 1.5), faint...
April 10, 2022 (Mühlhausen/Kraichgau: eVscope 2): M 101 photographed (app version 1.5), faint...
April 17, 2022 (Mühlhausen/Kraichgau: eVscope 2): M 101 photographed (app version 1.5), faint...

Observations July/August 2022

July 29, 2022 (Mühlhausen/Kraichgau: Vespera): M 101 photographed
August 7, 2022 (Mühlhausen/Kraichgau: Vespera): M 101 photographed (longer exposed)
August 22, 2022 (Mühlhausen/Kraichgau: eVscope 2): M 101 photographed

Observations June 2023

June 2, 2023 (Mühlhausen/Kraichgau: Vespera): M 101 photographed together with supernova SN 2023ixf

Observations August/September 2023 (Supernova still there...)

August 21, 2023 (Mühlhausen/Kraichgau: eVscope2): M 101 photographed; new image processing (DDT, app version 2.4.1), 10 min
August 25, 2023 (Mühlhausen/Kraichgau: eVscope2): M 101 photographed; new image processing (DDT, app version 2.4.1), 32 min
September 6, 2023 (Mühlhausen/Kraichgau: eVscope2): M 101 photographed; new image processing (DDT, app version 2.4.1), 6 min

Observations May/June 2024

May 14, 2024 (Mühlhausen/Kraichgau: Vespera Pro): M 101 photographed (21 min), poor and noisy
June 7, 2024 (Mühlhausen/Kraichgau: Vespera Pro): M 101 photographed (30 min), noisy

Observations March 2025

March 27, 2025 (Mühlhausen/Kraichgau: Vespera Pro): M 101 photographed (90 min)

References

Messier Catalogue - Messier 101: messier.seds.org/m/m101.html
Messier 101 (Wikipedia): en.wikipedia.org/wiki/Messier_101
Supernova SN 2023ixf: en.wikipedia.org/wiki/SN_2023ixf
NGC 5422 (Wikipedia): en.wikipedia.org/wiki/NGC_5422
NGC 5473 (Wikipedia): en.wikipedia.org/wiki/NGC_5473
NGC 5474 (Wikipedia): en.wikipedia.org/wiki/NGC_5474
NGC 5477 (Wikipedia): en.wikipedia.org/wiki/NGC_5477
NGC 5484 (Wikipedia): en.wikipedia.org/wiki/NGC_5484
NGC 5485 (Wikipedia): en.wikipedia.org/wiki/NGC_5485
H II Region (Wikipedia): en.wikipedia.org/wiki/H_II_region

On this Site

Appendix: My Own Photos

eVscope


M 101 - Mar 15, 2020	M 101 - Mar 23, 2020	M 101 - Mar 25, 2020

M 101 - Mar 15, 2020, photo on top processed	M 101 - Mar 23, 2020, photo on top processed	M 101 - Mar 25, 2020, photo on top processed

M 101 - Apr 19, 2020, fuzzy, processed	M 101 - Apr 21, 2020	M 101 - Apr 21, 2020, photo left processed

M 101 - Apr 22, 2020	M 101 - May 5, 2020	M 101 - Jun 11, 2020

M 101 - Apr 22, 2020, photo on top processed	M 101 - May 5, 2020, photo on top processed	M 101 - Jun 11, 2020, photo on top processed

M 101 - Jun 12, 2020	M 101 - Jul 3, 2020, sky too bright	M 101 - Jul 9, 2020, poor conditions

M 101 - Jun 12, 2020, photo on top processed	M 101 - Jul 3, 2020, photo on top processed	M 101 - Jul 9, 2020, photo on top processed

M 101 - Jul 9, 2020	M 101 - Aug 8, 2020, poor conditions	M 101 - Aug 19, 2020

M 101 - Jul 9, 2020, photo on top processed	M 101 - Aug 8, 2020, photo on top processed	M 101 - Aug 19, 2020, photo on top processed

M 101 - Aug 19, 2020	M 101 - Sep 8, 2020	M 101 - Sep 8, 2020

M 101 - Aug 19, 2020, photo on top processed	M 101 - Sep 8, 2020, photo on top processed	M 101 - Sep 8, 2020, photo on top processed

M 101 - Mar 6, 2021	M 101 - Mar 6, 2021	M 101 - Mar 6, 2021

M 101 - Mar 6, 2021, photo on top processed	M 101 - Mar 6, 2021, photo on top processed	M 101 - Mar 6, 2021, photo on top processed

M 101 - May 30, 2021	M 101 - July 18, 2021	M 101 - July 29, 2021

M 101 - May 30, 2021, photo on top processed	M 101 - July 18, 2021, photo on top processed	M 101 - July 29, 2021, photo on top processed

M 101 - Aug 20, 2021	M 101 - Aug 20, 2021, photo left processed

M 101 - Sep 8, 2021	M 101 - Sep 8, 2021, photo left processed

eVscope 2


M 101 - Apr 9, 2022	M 101 - Apr 10, 2022	M 101 - Apr 17, 2022

M 101 - Apr 9, 2022, photo on top processed	M 101 - Apr 10, 2022, photo on top processed	M 101 - Apr 17, 2022, photo on top processed

eVscope 2 (3)


M 101 - Aug 22, 2022	M 101 - Aug 21, 2023, 10 min	M 101 - Aug 25, 2023, 32 min

M 101 - Aug 22, 2022, photo on top processed	M 101 - Aug 21, 2023, photo on top processed	M 101 - Aug 25, 2023, photo on top processed

M 101 - Sep 6, 2023, 6 min	M 101 - Sep 6, 2023, photo left processed

Vespera


M 101, Jul 29, 2022 - original (82 frames = 820 seconds); dwarf galaxy NGC 5474 to the left		M 101, Aug 7, 2022 - original (191 frames = 1910 seconds); dwarf galaxy NGC 5474 to the left

M 101, Jun 2, 2023 - original (186 frames = 1860 seconds)		M 101, Jun 2, 2023 - original (186 frames = 1860 seconds); supernova SN 2023ixf marked (red dot); dwarf galaxy NGC 5477 center right

Vespera Pro


M 101, May 22, 2024 - 2000p (126 frames = 1260s)		M 101, May 22, 2024 - 2000p (126 frames = 1260s), processed

M 101, June 7, 2024 - 2000p (180 frames = 1800s)		M 101, June 7, 2024 - 2000p (180 frames = 1800s), processed

M 101, June 7, 2024 - 1800p (180 frames = 1800s), 1:1 section		M 101, June 7, 2024 - 1800p (180 Frames = 1800s), 1:1 section, processed

M 101, June 7, 2024 - 1800p (180 Frames = 1800s), 1:1 section, processed and denoised		Evaluation with nova.astrometry.net

Further NGC galaxies: NGC 5422, NGC 5473, NGC 5474, NGC 5477, NGC 5484, NGC 5485; for the HII regions within M 101 see page H II Regions.


M 101, Mar 27, 2025 - 2000p (540 frames = 90 min)		M 101, Mar 27, 2025 - 2000p (540 frames = 90 min), processed

M 101, Mar 27, 2025 - 2000p (540 frames = 90 min), processed and denoised (PAI)		Evaluation with nova.astrometry.net

M 101, Mar 27, 2025 - 2000p (540 frames = 90 min), processed from TIFF and denoised (PAI)		M 101, Mar 27, 2025 - 2000p (540 frames = 90 min), 1:1 section, processed from TIFF and denoised (PAI)

Further NGC galaxies: NGC 5422, NGC 5473, NGC 5474, NGC 5477; for the HII regions within M 101 see page H II Regions.