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M1 Crab Nebula (Sharpless 244)

Jan - March 2012

Messier 1 is the remnant of the supernova that exploded in 1054. Visually this is seen as a rather uniform object.  Using photography the complex tendrils of a roiling explosion can be more clearly seen.

This started out as a filler object.  I had completed work on SH 277 (the Horsehead area).  SH274 did not rise for a couple of hours after twilight. So the scope needed something to work on.  I inserted M1 as a low priority project before SH274.  Once work was completed on SH274 I managed to get enough data on M1 for a credible image.

I took sample shots with both Nitrogen and Sulfur, but decided that Nitrogen had the most interesting distribution.  The pictures below show the relative distribution, but I have tuned the colors for artistic merit and did not try to preserve the relative intensities of the various elements.

M1 in HON (CFHT palette)

HON (CFHT Palette)


M1 with only Hydrogen and Nitrogen

Hydrogen and Nitrogen Only

I found it difficult to pick out the Nitrogen portion of the signal in the HON image.  I created a new image that mapped

Hydrogen =  Red 
Nitrogen = Green
The distinct Nitrogen distribution is now clear

M1 Hubble Palette

Hubble (NHO) Palette

I frequently do not like the way it maps colors and it is presented here only because it only takes a moment to generate.

Active Map

In this image I overlay a map generated by SkyMap Pro with a larger crop of the area. Click to see the full size image.  It is easier to see the small galaxies in the larger version.

Map Overlay

Processing Details


Of course this is only what met the image quality standards. 

The images were processed with PixInsight.

Map of M1

LT area maparea map of M1
LT detail mapdetail map of M1
Area Map
detailed map

Copyrights for Photos

Creative Commons License
Except as noted, all work on this site by Robert J. Hawley is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License. This permits the non commercial use of the material on this site, either in whole or in part, in other works provided that I am credited for the work.