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Simms

Trouble finding the M101 (Pinwheel galaxy).

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With a bit of clear sky last night I decided to take the scope out and try locating some different objects than the usual suspects that I can see at this time of the year from my backyard (M42, M31, M45 etc), so bearing in mind the area of sky I have to view (not great) and the current level of light pollution (again, not great) I thought the Pinwheel might be a new DSO for me to find. However, I couldnt seem to find it and I wonder, what exactly could I expect to see with a 6" F5 Newt in so-so LP conditions? Am I looking for a slight blur ala M31 or will it be more star-like in a 40mm or 25mm eyepiece? I am pretty sure I was looking in the right area. Any advice would be great. Thanks!

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M101 is quite a large faint object with low surface brightness, so can be tricky to pick up in the eyepiece. It is do-able with a 6" in so-so light pollution. If you can get a fix on the location using Stellarium or other star map, use a low power and scan the location for a round-ish slight brightening of the background, best seen by moving your scope slowly back and forth in the spot where you think it is.

Once you've got it keep it in the eyepiece and scan your FOV with your eye. Gradually you'll get to see more detail extending away from the the galaxy's core, with a few faint stars dotted across the galaxy's arms.

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Thats great, thanks - hopefully I`ll get another chance this weekend to get out and have a look around for it.

How about Bins? should I be able to pick it up with a pair of 15x70 bins - even if just a faint glow?

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I've always found M101 really tough to see from my light polluted back garden.

Have seen it in an 8" on a moonless transparent night. I was surprised at how

large it appeared. I found it by following a crooked line of stars from Alcor/Mizar

that takes you close to it.

Keep trying ! Ed.

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Hi Simms, M101 is a difficult one due to the reasons already stated, I too had a bit of trouble locating it and when I did manage to observe it I understood why its so elusive :rolleyes:

Edited by Nexus 6

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I was surprised how easy M101 was to see at Kellling, of course this is a "dark sky" site. Too much magnification and you look straight through it. A nice low power eyepiece in say a 12" dob and its a wonderful object. I don`t stand a cat in hells at home....

Alan:D

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just been trying to find it on my 12inch dob with a 26mm ep, without success. May need a 40?

Edited by mindburner

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just been trying to find it on my 12inch dob with a 26mm ep, without succss. May need a 40?

Or a 16 inch :rolleyes::D:D

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just been trying to find it on my 12inch dob with a 26mm ep, without succss. May need a 40?

The problem with using a very low power ep with a fast Dob

under a light polluted sky, is that the view gets very 'washed

out' and the large exit pupil can waste light if it is larger than

your dark adapted pupil.

I do think you stand a better chance with the 26mm. I had lots

of tries to find M101 before finally bagging it.

Good luck ! Ed.

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Following this thread I had a look last night in the little 85mm Tak. The soft glowing core was very easy indeed to see, so I think the thing is just to get to a darker site. In the big Dob we can see the spiral arms , though they are faint, and at the end of two of them some outlying patches of bright star forming nebulosity.

I never saw it from the UK though I never tried for a really dark site. The first time I saw it was on holiday in Spain before I moved to France. The core was bright in a 120 achromat I took along.

So darkness beats aperture, I reckon, for this one. Ed is dead right about the exit pupil, too, because a big scope on a low power can exceed what will go into your eye. I have orderred a 26 Nagler for our Dob so as to get a 1 degree field with a smaller exit pupil than we have at the moment. First stop, M101!

Olly

Edited by ollypenrice

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yes, as olly has stated, a dark sky site would help in finding so much more in the night sky faint dso's being one group for a start! :)

Edited by Nexus 6

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I did this object over the last couple of nights. Spent a couple of hours searching for it just by scanning where it should be and using the correct DEC according to my setting circle. Couldn't find it at all. Then googled "How to find M101" and came up with the image below (Link: M101). I was using a 25mm ep on an 8" newt. The path below is relatively easy to follow (best to print it and turn it upside down if necessary so that you have the same orientation as in your eyepiece). However, having got to where it MUST be, I still couldn't see it! Just the merest ghost of a ghost. Absolutely no chance of seeing it unless you know where it is (in LP skies like mine). So I took a quick 30 second sub, and there it was - just! Second night I went straight to it, but still couldn't see it in the ep!

If you follow the diagram below don't do what I did and mistake the binary MIzar with Mizar and Alcor. In a 25mm ep on an 8" newt, Mizar and Alcor are quite a way apart. To find your first star hop you have to follow the line from Mizar to Alcor.

Look for the pattern of stars that I've circled, and notice the way the line intersects three of those stars. If you can see that, you're home and dry. But don't bank on seeing it in the eyepiece - it's nothing like M33 or even M81.

By the way, in my 15x70 bins, I could see it. Too much magnification blows it away.

Good luck! Let us know if you find it.

post-21238-133877538712_thumb.jpg

Edited by namreg
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In the big Dob we can see the spiral arms , though they are faint, and at the end of two of them some outlying patches of bright star forming nebulosity.

Olly

Saw two of the brighter knots on sat night. Quite breathtaking the first time you make them out, that's for sure :)

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I know exactly where the thing is but to date never seen it through an eyepeice in my 10". I've imaged it though :)

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you guys are great, some super advice. I will have a go this weekend with the great little star guide. Skies tonight are just a bit to orange

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I am located in a village near Karlsruhe, Germany, and can only parrot what others have said before me. i´ve been observing the late winter sky now for a couple days in a 10inch DOB and M51 and M101 were particularly hard to find. M51 seems to be placed at the wrong position in stellarium, in the actual sky it appears slightly lower. and M101 i can only see as a weak spot slightly brighter than the background, due to the problem mentioned by other posters before. it has a good magnitude, but is just too big so the light is spread out across the galaxy and the core isnt very bright either.

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I have found the core of M101 in 15x70 bins on an extremely transparent night, even with some LP around (when the sky is very transparent, this is not as big a deal, because there are few scatterers about). In a dark site (outside Dienville in France) it was easy in the bins, though it is much fainter than many other galaxies when it comes to surface brightness. Under slight LP it can be hard in a C8.

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With a 10" Reflector, M101 has eluded me for years! Far too diffuse for my location. Have managed to image it quite well, so at least I know im looking in the right place!

Matt

Edited by Vega

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I got M101 yesterday from a fairly dark location in my C8 and it was stunning. A big finder helps locating the right spot (star-hopping from Mizar, as in the image of Doug (Namreg)), but even in my 16x70 finder I could not see the object. However, in the 1.38 deg FOV of my Paragon it was easily spotted as a large nebula with not very prominent core, and clear indications of spiral structure. At 90x magnification in the Nagler 22mm the spiral structure was even more pronounced, against a darker background. From the suburbs in Groningen this is a much harder object.

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I did this object over the last couple of nights. Spent a couple of hours searching for it just by scanning where it should be and using the correct DEC according to my setting circle. Couldn't find it at all. Then googled "How to find M101" and came up with the image below (Link: M101). I was using a 25mm ep on an 8" newt. The path below is relatively easy to follow (best to print it and turn it upside down if necessary so that you have the same orientation as in your eyepiece). However, having got to where it MUST be, I still couldn't see it! Just the merest ghost of a ghost. Absolutely no chance of seeing it unless you know where it is (in LP skies like mine). So I took a quick 30 second sub, and there it was - just! Second night I went straight to it, but still couldn't see it in the ep!

If you follow the diagram below don't do what I did and mistake the binary MIzar with Mizar and Alcor. In a 25mm ep on an 8" newt, Mizar and Alcor are quite a way apart. To find your first star hop you have to follow the line from Mizar to Alcor.

Look for the pattern of stars that I've circled, and notice the way the line intersects three of those stars. If you can see that, you're home and dry. But don't bank on seeing it in the eyepiece - it's nothing like M33 or even M81.

By the way, in my 15x70 bins, I could see it. Too much magnification blows it away.

Good luck! Let us know if you find it.

Using this diagram, are the stars as seen with the naked eye, through the finder scope or through the main scope?

Neil.

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I asked SGL about this a couple of weeks ago. I also struggle to find M101 with my 300 Dob (and M51 actually). The answers were the same of course ... LP, diffuse, low surface brightness etc. I felt better that others find it hard too and it's not just me. I did actually find it last night but didn't find it that satisfying so I turned to my other nemesis DSO, M51 ... Which I did actually find. And enjoyed watching as more and more detail appeared to me. I went back to find M101 ... But no luck!

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From what I have been reading, M101 really is elusive and a bit of a challenge, i'll wait till this high cirrus cloud clears out then go back to it I think.

Neil.

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I haven't found it yet but will now be looking the way advised on this thread, cross fingers that we all get to see it before long.

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Visibility of M101 has very little to do with aperture or eyepiece type, everything to do with sky darkness. Best chance of seeing it is when it's overhead, so timing helps. The spiral arms contain a number of regions with their own NGC number: these are fun to track down at a dark site, though they probably require at least a 10" (I found nearly all of them with a 12").

M101 was discovered by Pierre Mechain on 27 March 1781, using a refractor with an aperture of 3 inches (76mm).

http://messier.seds.org/m/m101.html

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Visibility of M101 has very little to do with aperture or eyepiece type, everything to do with sky darkness. Best chance of seeing it is when it's overhead, so timing helps. The spiral arms contain a number of regions with their own NGC number: these are fun to track down at a dark site, though they probably require at least a 10" (I found nearly all of them with a 12").

M101 was discovered by Pierre Mechain on 27 March 1781, using a refractor with an aperture of 3 inches (76mm).

http://messier.seds.org/m/m101.html

I agree. You can see it in a 50mm finder here. Well, by 'see it' I mean that you can tell it's there...

High and dark is indeed the secret.

Olly

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