Messier 100 (M 100)

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 100 (NGC 4321) in the constellation Coma Berenices.

Introduction

The spiral galaxy M 100 in the constellation Coma Berenices is almost seen face-on, similar to M 99 and M 101, but much smaller than M 101.

In the Vespera mosaic, M 100 can be observed together with the spiral galaxy M 99 and many other small galaxies.

Between M 99 and M 100 there are the spiral galaxies NGC 4298 and NGC 4302, which form a strongly gravitationally bound pair (Holm 377 or KPG 332).

Close to M 100 there are the galaxies NGC 4323 (lenticular dwarf galaxy), NGC 4328 (elliptical dwarf galaxy), IC 783 (lenticular dwarf galaxy), NGC 4312 (spiral dwarf galaxy, edge-on) as well as some further smaller galaxies that are hard to spot on the photo.

M 100 (NGC 4321)	M 99 (NGC 4254)	NGC 4298 (Holm 377)	NGC 4302 (Holm 377)
Size: 7.5′ × 6.1' (Wikipedia) Distance: 60 million light years (Stoyan) Rating: * (Stoyan)	Size: 5.3' × 4.6' (Wikipedia) Distance: 60 million light years (Stoyan) Rating: * (Stoyan)	Size: 2.5' x 1.4' (SkySafari) Distance: 54 million light years (SkySafari) Rating: ---	Size: 6.0' x 1.1' (SkySafari) Distance: 47 million light years (SkySafari) Rating: ---

NGC 4312	NGC 4323	NGC 4328	IC 783
Size: 4.6' x 1.1' (Wikipedia) Distance: 36 million light years (Wikipedia) Rating: ---	Size: 1.1' x 0.8' (Wikipedia) Distance: 79 million light years (Wikipedia) Rating: ---	Size: 1.3' × 0.9' (Wikipedia) Distance: 20 million light years (Wikipedia) Rating: ---	Size: 1.2' x 0.8' (Wikipedia) Distance: 54 million light years (Wikipedia) Rating: ---

Map

The spiral galaxy M 100 in the constellation Coma Berenices (in the middle, higher up) (Image Courtesy of SkySafari Astronomy, www.simulationcurriculum.com)

The spiral galaxy M 100 in the constellation Coma Berenices together with M 99 and M 98 as well as some small galaxies (Image Courtesy of SkySafari Astronomy, www.simulationcurriculum.com)

My Best Own Photos

eVscope


M 100 - Mar 25, 2020		M 100 - Mar 25, 2020, processed (Polarr)		M 100 - Mar 25, 2020, processed (Polarr), potential galaxies marked

*) Top (from left to right): NGC 4328, NGC 4323; bottom (from left to right): NGC 4312, UGC 7425?, IC 783

Vespera


M 100 with M 99, Jun 8, 2023 - original, 3600s, mosaic		M 100 with M 99, Jun 8, 2023 - large, 3600s, mosaic, processed

		Evaluation* with nova.astrometry.net, large

*) Further galaxies: IC 781, IC 783, IC 3177, IC 3238, IC 3244, NGC 4262, NGC 4298, NGC 4302, NGC 4322, NGC 4223, NGC 4328, NGC 4312

Vespera Pro


M 98, M 99 and M 100, Apr 4, 2025 - 2100p, 56 min, mosaic		M 98, M 99 and M 100, Apr 4, 2025 - 2100p, 56min, mosaic, processed and denoised (PAI)

M 98, M 99 and M 100, Apr 4, 2025 - 2100p, 56min, mosaic, processed from TIFF		M 98, M 99 and M 100, Apr 4, 2025 - 2100p, 56min, mosaic, processed from TIFF and denoised (PAI)

M 100 with NGC 4312, Apr 4, 2025 - 1800, 56 min, 1:1 section from mosaic		M 100 with NGC 4312, Apr 4, 2025 - 1800, 56 min, 1:1 section from mosaic, processed

		M 100 with NGC 4312, Apr 4, 2025 - 1800, 56 min, 1:1 section from mosaic, processed and denoised (PAI)

M 100 with NGC 4312, Apr 4, 2025 - 1800, 56 min, 1:1 section from mosaic, TIFF processed		M 100 mit NGC 4312, Apr 4, 2025 - 1800, 556 min, 1:1 section from mosaic, TIFF processed and denoised (PAI)

		Evaluation* with nova.astrometry.net

*) Further galaxies: IC 783, NGC 4312, NGC 4322, NGC 4323, NGC 4327, NGC 4328

My Own Observations

Observations March 2020

March 23, 24, and 25, 2020 (Mühlhausen/Kraichgau: eVscope): M 100 photographed, best on March 24.

Observations June 2021

June 1, 2021 (Mühlhausen/Kraichgau: eVscope): M 100 photographed (n.o., r.f.), new image size and processing. Discovered 4-5 more galaxies!

Observations June 2023

June 8, 2023 (Mühlhausen/Kraichgau: Vespera): M 100 photographed together with M 99 and some more galaxies.

Observations April 2025

April 4, 2025 (Mühlhausen/Kraichgau: Vespera Pro): M 100 photographed together with M 98 , M 99 and NGC 4298 & NGC 4302 as well as further small galaxies (56 min).

References

Messier Catalogue - Messier 100: messier.seds.org/m/m100.html
Messier 100 (Wikipedia): en.wikipedia.org/wiki/Messier_100
Messier 99 (Wikipedia): en.wikipedia.org/wiki/Messier_99
NGC 4298 (Wikipedia): en.wikipedia.org/wiki/NGC_4298
NGC 4302 (Wikipedia): en.wikipedia.org/wiki/NGC_4302
NGC 4312 (Wikipedia): en.wikipedia.org/wiki/NGC_4312
NGC 4323 (Wikipedia): en.wikipedia.org/wiki/NGC_4323
NGC 4328 (Wikipedia): en.wikipedia.org/wiki/NGC_4328
IC 783 (Wikipedia): en.wikipedia.org/wiki/IC_783

On this Site

Appendix: My Own Photos

eVscope


M 100 - Mar 23, 2020	M 100 - Mar 24, 2020	M 100 - Mar 25, 2020

M 100 - Mar 23, 2020, processed	M 100 - Mar 24, 2020, processed	M 100 - Mar 25, 2020, processed

M 100 - Mar 25, 2020	M 100 - Mar 25, 2020, processed	M 100 - Evaluation with astrometry.net

M 100 - Mar 25, 2020	M 100 - Mar 25, 2020, processed (Polarr)	M 100 - Mar 25, 2020, processed (Polarr), potential galaxies marked

*) Top (from left to right): NGC 4328, NGC 4323; bottom (from left to right): NGC 4312, UGC 7425?, IC 783

Vespera Pro


M 98, M 99 and M 100, Apr 4, 2025 - 2100p, 56 min, mosaic		M 98, M 99 and M 100, Apr 4, 2025 - 2100p, 56min, mosaic, processed and denoised (PAI)

M 98, M 99 and M 100, Apr 4, 2025 - 2100p, 56min, mosaic, processed from TIFF		M 98, M 99 and M 100, Apr 4, 2025 - 2100p, 56min, mosaic, processed from TIFF and denoised (PAI)

M 100 with NGC 4312, Apr 4, 2025 - 1800, 56 min, 1:1 section from mosaic		M 100 with NGC 4312, Apr 4, 2025 - 1800, 56 min, 1:1 section from mosaic, processed

		M 100 with NGC 4312, Apr 4, 2025 - 1800, 56 min, 1:1 section from mosaic, processed and denoised (PAI)

M 100 with NGC 4312, Apr 4, 2025 - 1800, 56 min, 1:1 section from mosaic, TIFF processed		M 100 mit NGC 4312, Apr 4, 2025 - 1800, 556 min, 1:1 section from mosaic, TIFF processed and denoised (PAI)

		Evaluation with nova.astrometry.net