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M31...help me find it!


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Heys guys, Im am trying so damn hard to get M31 in the scope. I know it is inline with the knees of andromeda, about the same distance away the knees are from each other on the same side as cassiopiea, but I cant locate at all. Everyone says you can see it with binoculars....I cant! I know it's the biggest galaxy, and thought it would be easy to spot. Can someone give me some pointers or some stars to look out for...it's easy on starry night ....but when im outside I cant see it. Would light pollution be a big threat? :saturn:


without light pollution


with light pollution


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Hi there. I managed to see a faint blob on a clear night with my 4.5" reflector with next to no knowledge of the skies whatsoever (I didn't even know those two stars I used to find it were andromeda's knees).

I spent a good while just working out where it was supposed to be by looking at a sky chart (I used the diagonal of Pegasus' Square, and the same distance again, then 2 stars along at right angles), then another little while trying to see something there with my naked eye. I saw a faint blob, pointed my RDF at it and looked in the scope. To my luck and surprise, there it was in my FOV. I then centered it and used a 10mm EP for the best view. It might well be easier to use a finder scope rather than an RDF, as the magnification will help you to actually see it. I did find it very difficult to see with my naked eye.

Advice merely out of my very limited experience.


P.S. I think LP is a very limiting factor for such objects. What scope are you using BTW?

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Everyone says you can see it with binoculars....I cant!

And I thought LP was bad round my way - its definitely visible in 50mm bins (obviously so) and on moonless nights you can just about see it with the naked eye and a bit of the old averted vision.

I wouldn't get too excited if your scope is less than 90mm - in my etx90 the view ain't that much different from my bins.

Maybe an apo would be better but I've never looked through one myself.

Don't forget to get your finder aligned so the view is the same as the eyepiece.

The better its aligned, the easier it is to find stuff.

Another thing, if your not in equatorial mode, there's nothing wrong with using line of sight -

crouch down and look along the scope to see what its actually pointed at and not what you think its pointed at.

I'm fairly new to using scopes myself so I hope these tips don't sound patronising.

It ain't rocket science, you'll find it soon enough.

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I saw it from my back garden the other night. astrophethean used basically the same method as me. According to 'Turn left at Orion':

Locatethe Great Square (of Pegasus I think) From the northeast corner find three bright stars in a long line, arcing accross the sky west to east, just south of cassiopeia. the big W. From the middle of these three stars go north towards Cassiopeia past one star, to a second star, Nu Andromedae in a slightly curving line. The galaxy is just barely visible to the naked eye (Yeah right!) just to the west of Nu Andromedae.

In The Finderscope: Aim at Nu Andromedae, and the galaxy should be visible in the finderscope.

I aimed roughly using the stars with my red dot finder then found it in the Finder scope, then moved to the main scope and sure enough right there!!! This was when the moon was out as well, so you should be able to find it even with some light polution.

Hope the above helps, keep with it, its an amazing thing to see for the first time, all the best if you have found it yourself without GoTo etc.

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thanks for your views, I think Ill try it again next week without the full moon!!!

let you know how I get on... Ill try and get it with my 10mm.

Ive only got the Celestron 114 compact. But Im liking the feel of it already.

damn :moon:

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I've had the same problem, I can only rarely get to a dark sky site as I work at night and my back garden has horrible LP so andromeda is still an unsolved target for me, I know where to look, I just dont see it Maybe one of these mghts, my night off will coincide with a clear, moonless sky so I can take a trip down to the coast, find Andromeda, and wait for the tidal wave to hit :)

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But its not a dark sky only thing. I'd have jumped in earlier, but I was expecting loads of "found it, thanks" responses. I can see it from my undark site as a very small fuzzy blob in 10X50 Bins. It doesn't look big at all because you won't be able to see most of it. This bit about it being loads bigger than the moon doesn't take account of the fact that you will only see the very brightest bit, the core, unless you are in a dark place, with lots of aperture and pointed straight at it.

To find it as I do:-

Look for the big W shaped Cassiopeia somewhere round straight up at this time of the year (it moves depending on the time and the season - these things migrate a bit). Turn so that the W is the right way up as if it was written on a piece of paper.

Under the W is a straight line of bright stars spanning half the sky, and one is pointed at by the arrow formed by the three stars on the right hand part of the W.

Once you have that star, move towards the W slowly with the Bins, until you get to another star, not as bright this time. Keep going until you get to the next one, which is a little out of line if you're going straight towards the W. Next to that star is a tiny fuzzy thing. That is actually the Great Andromeda Galaxy.

Next you can point your telescope at it and see it as a slightly bigger fuzzy blob, unless you have plenty aperture (over 10") or a dark site. Use the widest angle EP you have otherwise you will really struggle. 25mm is probably a minimum, depending on your 'scope, 30 or 40mm being needed for longer (SCT / Mak) types.

Finally, stick a camera on the 'scope and you can begin to see the extent of the thing, it doesn't get really big until you have a camera on it for lots of minutes.


Captain Chaos

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hows saturn at the mo? clear? im north facing :)

You don't have to stay up so late to see it now. An unobstructed view to the east /south east

and you could catch it around 1am, + or -. I have to wait till 2am coz the house is in the way.

Wish I had a bigger scope to see the Cassini divsion though.

Good luck with the M31 hunting :)

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