Your observations of M31?

[Size9Hex]

I've just has a bit of a breakthrough with M31. Interested to know what other folks experiences when observing this one?

The reason for asking... It was my first DSO a year ago which may echo with quite a few other people. I've viewed it countless times since then, during which my observations of other targets seem to have improved, while M31 has remained (until this week) as featureless as my first view of it.

But earlier in the week from a dark site, I suddenly saw the big dust lane for the first time and also that the brightness of the core is very lop sided. The skies here had an impressive Milky Way through Cygnus, with M31 being a direct vision naked eye target (but only barely). NELM 6 and a bit. 10" f4.7 dob, 14mm 82 degree eyepiece.

So far, so normal. Dark skies help etc. But having seen the above, I compared the view at home (edge of town, NELM 5 and a bit at the zenith, probably less than 5 as low down as M31, with a very washed out Milky Way in Cygnus at the zenith, and M31 just about visible in averted vision naked eye). In these conditions I'd never seen the dust lane, but after the dark site trip I spotted it first time from home. The contrast was almost zero, but I followed it through groups of field stars, and when I compared the location against an image, there was no doubting it.

I'm honestly amazed it was there the whole time under pretty average sky conditions (not awful, but far from great). I had sort of given up on M31, but this experienced has shown there's more potential than I realised. I've seen it referred to as a beginners target, but it has really not given up any secrets easily to me, and now I'm quite fired up to have a proper go at it in the coming months.

So, what can you see? What kit? And what are your skies like? And have you had a really good go at it?

[Size9Hex]

Just to add an image to clarify what I've suddenly been able to see. The green line shows what previously seemed to be the edge of M31 on the M101 side. The key to seeing the dust lane along this green line was realising that the edge of the core is the dust lane. The red lines indicate the shape of the lop sided brightness in the core. There was no hard outline of course, but the overall shape of the glow was like two overlapping almonds. Overall the glow did extend beyond this, but this was the impression of the shape of the brightest region. This asymmetry came as a complete surprise. Looking forwards to seeing what else can be pulled from this in the coming months! 

 

[ollypenrice]

Good post. Knowing what to look for helps you to see it. Does it lead you to invent what you are seeing? I don't think so. I do a lot of astrophotography and still quite a lot of visual and I think that what I find in pictures helps me to find more at the eyepiece. Not always though, which is why I don't think anticipation leads to invention.

I live at a very dark site and even with my poor unaided eyesight I can see M31 as an elongated streak when low in the sky. Easier as it gets higher. In low power bins it is always spectacular. Stepping up to the 20 inch Newt, though, it is very variable despite the aperture. For a thrilling view of the two main dust lanes it needs to be high in the sky. In this respect it is ike any other galaxy. A good elevation makes all the difference. I don't think this point can be over stated and I have fairly good horizons, outstandingly good by the standards of mainland Europe. (We can image down to the horizon and often do.) Even so, higher is better - by a mile.

Olly

[rockystar]

I think my experience of it mirrors your initial opinions, but I haven't had a good dark sky view of it yet. I have had the binoculars on it a couple of times in the last few weeks, and been quite impressed, and your comments here mean I'll try again at home (one it gets over the garage).

knowing what you are looking for does help though. The first time i saw M13 it was an impressive fuzzy ball, but now, under the same conditions and with the same equipment, I can make out many stars.

[Size9Hex]

Thanks Olly, interesting comments. I agree images are a help in supporting visual observations. It this case I spotted the dust lane and lop sided core first (not to pretend I'd never seen an M31 image of course, but I didn't really know where the dust lane was), and verified against an image later, although sometimes (not often though) I do scrutinise an image before I observe a target. I find if I have prior knowledge from an image (or from anywhere), I try to challenge myself with a very specific question (to which I don't know the answer) at the eyepiece to verify what I'm seeing if I have any doubt. E.g. where exactly is the feature I think I can see, or what is it's orientation?

[Size9Hex]

Thanks Rockstar. Hope you get a good view of it too as it gets higher. Interesting you mention M13 - a similar experience for me in that it is better now than a year ago, but in comparison to M31, it has got better incrementally whereas M31 suddenly just clicked. Off on a tangent here, but have you seen the propeller (three dark lanes shaped like a Mercedes logo) in M13? There's so much to see in this one!

[orion25]

Paul,

M31 was my first DSO so many years ago when I got my first reflector (Tasco) and at the time I was excited just to see a slightly oblong little fuzzy spot. Nowadays, I use an Astroview 6 in my backyard with Bortle 5 skies, and on a night of good seeing I can just make out some dust lanes. I photographed M31 through my 127 Mak-Cass and was able to image hints of the lanes around the core, similar (but with a little more detail) to what I can see through the eyepiece in my reflector (8X30s):

 

[FenlandPaul]

Great post, Paul.  I don't think I've ever teased that out of M31 but then, shamefully, I don't think I've ever studied it quite so much when it's been high up because , oddly, it's so bright and obvious!  That's a terrible reason and I will make amends.  Thanks for posting such a good description and annotated pic.

Paul

[niallk]

Yeah first viewings of M31 didn't yield much detail, but it was my first galaxy, and it took several attempts to find it, so I was thrilled.  After more practice, with my 250px I see two dust lanes, catching the next one out from your green line in your pic.

[ronin]

A dark sky makes a huge difference, but dark means dark not just a little darker.

OVer on CN (I think) someone compared the 2 by an easy, although imaged, comparison. Using exactly the same equipment and camera and settings they took 2 single shot images of M31, bith were just taken and no processing. It read that they wanted to actually make as direct a comparison as reasonable between the 2 enviroments. The darker location one showed up a large amount of detail that was lost in the not-so-dark location one.

[Davesellars]

The problem is that with M31 naturally it seems a good idea to use as little magnification as possible because the object is large... Or because it may fit in m32 and possibly m110 in to the same view.  This is nice and if you have sufficiently dark skies around mag 5 you should have no issue in seeing the cores of all three.

However, if you want to see more from the central core of m31 you need to apply more power to improve the contrast otherwise the sky background in a mag 5 ish sky and lack of contrast means you can't see fainter detail.  If you lower the exit pupil to 3 or better still 2, while you won't have the entire thing in the FOV with a bit of work you should be able to see those dust lanes that you've marked out.

[jetstream]

Wait until you see the other dust lane... On a good night M32 will be buried in the glow of M31 and the dust lane will "round the bend" a bit. A good zoom can be of much benefit on the lanes, for fixed fl ep's in my 10" I use from 12.5mm -21mm widefields with good luck.

[FenlandPaul]

3 hours ago, jetstream said:

Wait until you see the other dust lane... On a good night M32 will be buried in the glow of M31 and the dust lane will "round the bend" a bit. A good zoom can be of much benefit on the lanes, for fixed fl ep's in my 10" I use from 12.5mm -21mm widefields with good luck.

"Buried in the glow of M31". Surely only you, Gerry, could complain about the light pollution caused by a galaxy 2 million light years away!!

[Size9Hex]

Thanks for the latest replies everyone!

@niallk good effort on the second dust lane in the 250px. What sort of skies was that under?

@FenlandPaul good luck with it. I think I'm similar to you. It's bright and obvious, and I spent loads of time looking at it early on before I got my eye in. Glad this post might encourage more folks to come back to M31 and see something new.

@jetstream as always, I'm in awe when I try to picture what you must being seeing under your skies!

@Davesellars thanks that's some really good practical advice.

[John]

There is some excellent advice in this thread on how to get more from M31

Over the past couple of years I've been able to, at last, pick out the main dust lane and using higher powers has been the key to this - and also realising just how much of this object there is and therefore that the dust lane is somewhat further out from the core than I'd been expecting

I've found an eyepiece such as the 13mm Ethos very useful - it gives 122x with my 12" dob, an exit pupil of 2.4mm and is showing .81 of a degree of sky.

M33 is another galaxy that is worth spending some time on. As well as it's extensive and subtle structure, it has nebulae that we can see with our scopes too !

 

[Size9Hex]

5 minutes ago, John said:

... and also realising just how much of this object there is and therefore that the dust lane is somewhat further out from the core than I'd been expecting

Absolutely bang on the money. It was the same for me. Funnily enough, now you've pointed this out I realise it was exactly this realisation that led to me spotting the arms in M81 miles away from core. Ignore the tempting easy core, and treat the surrounding almost as if you were viewing a really faint extended nebula.

[alan potts]

Interesting post and some nice replies. Personally I feel my best views of it are with either my 10.5 x 70 binos or the two short scopes I have with low power, I like to see it as a whole. i have had the 18 inch on it a couple of times but only seen a part of it due to the magnification factor and this for me takes the shine off it. It was of course brighter with the large scope but just somehow not as pleasing to look at. That reminds me it is about time I used these scopes again they get over-looked these days.

Alan

[Paz]

I've not checked out m31 for a while but I notice the same effect on other targets where once you have seen more detail in good conditions you seem to be better able to pick out slightly more details in worse conditions as you know better what you're looking for.

[rockystar]

I had a look at M31 again last night, but I still couldn't really make much out and I'm ashamed to say I just put it to one side and said "I'll save that for a dark site".

However, I did have a look at M11 last night (for the first time), and if I was a complete beginner I'd probably have written it of as a bit of a fuzz, but I has a bit of an idea what I expected to see, a bit of patience and persistence enabled me to start to make out the shape and resolve some of the fainter fuzziness into stars.

[VilleM]

For me trick to see the dustlanes more clearly is to use very wide FoV. Ive had best views when entire galaxy fits in the view with my 2.75" APO at 15x. Core is way brighter with my 8" Newtonian but its too long to make dustlanes visible clearly (f/6).

-V