Can I see M51 with this setup ?

[johnb]

Hi

Well I setup my Skywatcher Explorer 250 OTA and did the normal polar alignment and 2 star alignment etc, I went to various objects i.e. Sirius, Venus and the Beehive and all were perfectly centred (was using my 25mm Super Wide EP) so I know the scope was properly setup. I then tried M51 and could see nothing at all ? I would of expected to at least see a smudge ?

Regards

John B

[gfletcher]

Hi John

I have the same OTA as you have.

I have seen M51 through it on nights of good seeing.

The last few nights hav'nt been very transparent so detecting it would be more difficult.

What you will notice is 2 stars quite close to each other with some form of halo around them.

Under dark skies and good transparency you will definitely be able to pick out M51.

hope that helps

Graham

[russ]

M51 is a real tricky customer from a light polluted backyard. I can see it with my 8" but only on good nights and even then it could hardly be described as obvious. It could be you were expecting something brighter and that it was actaully there. Sometimes it helps to move the scope around a bit for the eye to catch the faint smudge.

[johnb]

Thansk to all, appreciated.

John B

[part timer]

Just to add, I can 'detect' M51 on a really clear night when it is over head through my 6".

Can't really say I see it but I can tell it's there. I have terrible light pollution. M51 is one of the tricky ones in that I can see fainter objects very well as they are more compact. M51 is face on so the light is more spead out and easily swamped by light pollution.

[hemihaggis]

well i can spot it quite easily through my 5" sw mak .. also sirius is not too good to use for alginment just now ..very far west and sinking below horizon before dark ?? ..

[RobH]

M51 is visible in my 4 inch Tal refractor on a good night so your 10 inch will see it easily.

Cheers

Rob

[ZOG]

I struggled for ages with M51 in the 12" dob. Then, one night it was just there, and a lot bigger than I expected.

Just keep trying and you'll get there.

[acey]

In a dark sky you can see M51 with binoculars, and its spiral arms are visible with an 8-inch. At a light-polluted site you can struggle to see it at all with a 12-inch. It all depends on sky darkness, because the key thing is the contrast the object makes against the background sky. This is true of any galaxy or other "faint fuzzy" which is not a point source. If the object's total surface brightness is not sufficiently higher than the surface brightness of the sky, then it won't be visible, no matter the aperture.

This also applies to the Milky Way. If you can't see its glow with the naked eye then you won't see it through binoculars or a telescope (though you will resolve individual stars). Many galaxies (including M51) have central cores with a higher surface brightness than our own Milky Way, and it is possible to see these through a telescope when the Milky Way is not naked-eye visible. But to see galaxies easily and in detail, you want a sky in which the Milky Way is visible. The only cure for light pollution is to get as far away from it as possible.

[John]

As an interesting comparison of the impact of light pollution , the view of M51 with my 6" refractor from the fairly dark skies at the SGL5 star party was about the same as I can get on a really good night with my 10" newtonian from my back garden with moderate light pollution. I felt I could almost see spiral structure with my 6" at the star party - with the 20" dobsonian that I also tried that night there was absolutely no doubt though !!!

[russ]

As an interesting comparison of the impact of light pollution , the view of M51 with my 6" refractor from the fairly dark skies at the SGL5 star party was about the same as I can get on a really good night with my 10" newtonian from my back garden with moderate light pollution. I felt I could almost see spiral structure with my 6" at the star party - with the 20" dobsonian that I also tried that night there was absolutely no doubt though !!!

I had a similiar experience at the weekend John. We had a our first dark sky observing night in the depths of the New Forest and M51 was at the top of my to do list. As with Kelling 2004, the difference was just amazing, just so bright and easy to find. It's hard to believe i have to struggle so much back home. In my 8" dob we could see some spiral structure with averted vision. I was hoping to see it in the C11 but that never came off.

[Moonshane]

I'm worried now! I saw what I am sure was M51 and NGC 5195 from my reasonably badly light polluted back garden recently. It was in the right place and was like a pair of misty eyes peering out of the gloom with bright specks at the centres. I thought I detected hints of a link between the two but this was less clear. This was a good night and I saw M81 and 82 very clearly too. This all with the 12" dob and 33mm SWAN. The guidance in Turn Left at Orion was really helpful in finding this, after I remembered that the finder view was reversed to my right angled viewer!

[pvaz]

M51 is fainter then M81 and 82 and sensitive to LP. The "bridge" between the too is very faint and needs really dark skies.

I have almost no light pollution at all as I live in the middle of vineyards about 1km away from a very small fisher village (around 500 inhabitants). Detecting the galaxies on my 8" is pretty easy however I only get hints of the spiral structure and the bridge on very steady seeing nights.