A fleeting glimpse of C23, NGC 752

[WaveSoarer]

The sky cleared for a spell last night, though there were still patches of cloud floating past, and so I got the scope setup for a bit of observing and imaging. I start hopped from Almaak to bAnd and after a right angle turn to the line of three stars HIP11185, the faint HIP11099, and HIP11090, I managed to find C23. It lies close to HIP11185 on an approximate line back to bAnd. It is pretty faint but with slightly averted vision is certainly looks like a smudgy streak. I only viewed it with my 20 mm EP but I think that a little experimenting at higher power may have helped. I found that that the best views of M51, on previous sessions, were with my 10 mm EP which really helped to contrast the galaxy against the background glow of the sky. The cloud rolling back in last prevented me trying this sadly. Hopefully, I'll get the chance to try again soon.

[cotterless45]

C23 is a fabulous bright galaxy especially with a dark sky.

Last decent view was on Skye with a 10" Lightbridge, astounding with dust lanes and stars in the foreground,.

I usually catch galaxies using a 25mm giving x48 in the ota. Then crank the magnification up from x80 to x120 wide as possible. Higher magnification certainly works with light pollution, up to the point of not seeing due to low surface brightness. Certainly the case with The Whirpool.

Old Nick.

[WaveSoarer]

Briliant stuff Nick. What a cracking notebook you have too. It's interesting what effect changing the EP power has on the eye's ability to see detail in fainter objects. It is a ballance though as you say and it's wel worth trying different EPs to find the most suitable for a given occasion.

[cotterless45]

Yep, that's why I've got 24 eyepieces, mostly off Fleabay. Absolute crackers are the old school

8.8 mm UWA Meade 4000

10 mm Vixen SPlossl

7.5 and 5 mm Celestron Ultima.

Lovely to catch galaxies in the Hyperion and 15mm SW Panorama.

It's worth keeping an eye on Fleabay ,

Old Nick.

[WaveSoarer]

Fantastic Nick. I don't have that many but I have a range from 32 mm (Plossl) to a 2 mm. The 2 mm is no good for my 200p as the view is just fuzzy. I might have a look for a 3 mm which is on the seeing limit according to http://www.stargazing.net/naa/scopemath.htm

[acey]

WaveSoarer, you're talking about the edge-on galaxy NGC 891, which is number 23 in the Caldwell list. NGC 752 is an open cluster, also in the Caldwell list (number 28).

NGC 752 is a fairly easy naked-eye object from a dark-site - I call it the "M33 impostor", because the fuzzy patch of NGC 752 can fool anyone who's looking for M33 with the naked eye and is in the right general area but the wrong place (it fooled me when I first saw it naked-eye). In binoculars or a small scope it's an obvious open cluster. It was first discovered by Caroline Herschel, William's sister.

NGC 891 is a tougher target - and was also discovered by Caroline Herschel. It lies due east of Almaak (by about 3.5 degrees) so one way of finding it is to aim at Almaak, then just leave the (undriven) scope pointing at the same spot in the sky until NGC 891 drifts into the field of view. A better way is to get the exact spot by hopping along field stars as you did, because it's not necessarily the sort of target that leaps out at you. The dust lane which runs right along the galaxy can be seen in an 8" scope (and Nick has caught it well in his sketch).

With any object it's always worth going up through your full magnification range: small targets are best at high power, and that's true for galaxies as much as anything else. The limiting factor with galaxies tends to be light pollution, which can make galaxies disappear at medium or high power. At a dark site you can crank it right up - I go up to a 4mm eyepiece on my 12" (x375) when viewing galaxies, and some of them would stand higher if I could track the dob fast enough. On my old 8" f6 I never went higher than an 8mm EP (TeleVue plossl) when viewing galaxies at my dark site but you might get away with more if your sky is dark enough and your eye is up to it.

[WaveSoarer]

Thanks for this very detailed comment Acey. My notebook has the right NGC number so I don't know what I did there. I'll have a look for the cluster as it's in an easy part of the sky from my garden at the moment.

That's very sound advice on eyepieces. It's impressive how high a power you can use at a truly dark site. I haven't taken my scope anywhere apart from my garden as the sky isn't bad though not perfect. I should try doing this at some point.

[WaveSoarer]

I'm just back in after viewing NGC 752 (C28) with my binoculars. I see what you mean about getting confused with M33. It's similar in brightness and it's roughly the same size - though it appeared slightly bigger to me. A very interesting object which I'll need to revisit with the telescope. Thanks for the heads up Acey.

[WaveSoarer]

Oops. It appears that I was looking at this, C28, the other night (and reported elsewhere on SGL) as I stumbled across it when I was originally looking for the location of C23 with binoculars. It was on the same page on my notebook and I just copied down the wrong NGC number for the title of this thread. Interestingly, I now know that the curved asterism just next to it is called The Golf Putter.