However,if there is the slightest light pollution around ,things start going not very well when you try to spot the Crab Nebula.
Just looking to the parameters it shouldn't be like that : M1 have a visual magnitude of 8.4 mv.
But this light of a 8.4mv star is spread over an oval area of 8' x 4' or about 25 square minutes so the surface brightness is dropping to 11.9 mv.
To see stars of 12mv ,one need a six inch telescope and even in that instrument,those stars will be in the faint league ,in the last half of accesible magnitudes.
This is why is hard to find M1 by scanning the area.
Let's go another route...
Here is a 100% proof method to find the supernova remnant Messier 1 , aka Crab Nebula.
At one degree West-North West of star Zeta Tauri there is STF 742 ,a double star of 7mv.
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| Double star STF 742 at one degree W-NW of Zeta Tau |
The primary star and the companion of STF 742 are separated by 4.16''.
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| The page of STF 742 on StelleDoppie |
On 25-th of November it was not hard to notice at 33x /Plossl 25mm ,the binary character of STF 742 in my 60x828mm ''zoth'' refractor.
The power of 92x/Plossl 9mm confirmed I was spot on STF 742.
I knew (from many previous observations) that M1 IS IN THE SAME FIELD WITH STF 742.
Altough dim ,quite dim, M1 was there ,as expected in the visual field of 94arc minutes at 33x.
Pumping up the power to 92x did not bring additional details.
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| M1/ Crab Nebula in the same 90' field with STF 742 60mm F/14 refractor at 33' /Plossl 25mm |
To summarize , my trick to find M1 : search for double star STF 742 and center it in an eyepiece providing 80 or 90 arc minutes.
Once you are sure your telescope is centered on STF 742, scan carefuly the field because M1 is hiding somewhere there.
My trick is working for observations made from the downtown of our 180.000+++ city.
Good luck !
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