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Can I see other galaxies?


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I just got my first telescope on Sunday I got my first telescope, and I was wondering if I would be able to see any.

It's aperture is 80 mm. I have a 3x magnification lens, then a 25 or 10 mm lens behind that.

Thanks.

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Yes you can see other galaxies, but not like the photos you can see around here. Visually galaxies look like "clouds of light" or "gray smudges". I've seen over 50 galaxies and only been able to observer some structure (dust lanes) on 2 of them under dark skies and perfect conditions.

80mm is not a great deal for this types of objects as they are very dim and require more aperture, however you'll be able to see the brightest ones under dark skies (without artificial light around).

The magnification an eyepiece provides is given by the telescope's focal length over the eyepiece (EP) focal length (FL). For instance, if your scope haves a focal length of 1000mm then when you put the 25mm EP in, you'll get 40x (1000mm/25mm = 40x).

I assume the 3x lens you talk about is a 3x barlow lens, which used in between the scope and the EP triples the magnification you'd get without the barlow.

For galaxies you want to stay at low mag, as the higher the mag the more you scatter the light and that makes dim objects, such as galaxies, even harder to see.

BTW, love your sig.! :)

Edited by pvaz
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When I started out I had a 60mm refractor and managed to find a few galaxies with that (once I worked out where to look !). I found M81 and M82 in Ursa Major the most impressive in a small scope (better than M31). With a low power eyepiece you can see both of them in the same field of view on a dark night. You do need dark nights for galaxies, even with big scopes. Any moonlight or light pollution drowns them out really easily.

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You should be able to see most Messier galaxies with nothing more than 15x70 binoculars (Messier didn't have anything better than that) but dark skies make the difference.

With an 80mm the Messier galaxies should be visible under dark skies, maybe even a couple of the NGCs.

As to the binos, a 15x70 haves 2 lenses of 70mm aperture. If you calculate the area of the 2 lenses combined it will be greater then the area of an 80mm diameter lens. Of course then the brain needs to combine the 2 images and I have no idea how efficient it is.

70mm lens area = 3846,5mm^2, so that's 7693mm^2 for the 2 combined

80mm lens area = 5024mm^2

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[quote name=

70mm lens area = 3846,5mm^2, so that's 7693mm^2 for the 2 combined

80mm lens area = 5024mm^2

Ah, but it doesn't work like that! Close one eye and things don't become perceptibly less bright. However, I have never read a comptetent explanation of how doubling your lenses does affect apparent brightness. The effect is very disappointing in terms of what you can see. Again, close one eye when using bins. Remarkably little happens!

Andromeda (M31) is in fact visible naked eye at a dark site. My indifferent-to-poor 57 year old eyes can see it easily as a tiny elongated streak like a stretched star. We have a very low grade 80mm used as a finder on a big scope and that does get to many, many galaxies from this site including a host of NGCs.

Galaxies like to be seen near the zenith if possible because they need contrast and show best away from the inevitable sky glow.

Olly

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OBJECT

TYPECONRADECMAGSUBRChall catNGC DESCRSIZE_MAXSIZE_MINM 31GALXYAND00 42.7+41 163.413.51!!!eeB;eL;vmE189 m61 mM 81GALXYUMA09 55.6+69 046.913.22! eB;eL;E 156;gsvmbM;BN24.9 m11.5 mM 104GALXYVIR12 40.0-11 37811.63!vB;vL;eE92;vsmbMN8.6 m4.2 mM 32GALXYAND00 42.7+40 528.112.43vvB;L;R;psmbMN8.5 m6.5 mM 49GALXYVIR12 29.8+08 008.413.23vB;L;R;mbM;r9.8 m8.2 mM 64GALXYCOM12 56.7+21 418.512.73!vB;vL;vmE120;bM;SBN10.3 m5 mM 82GALXYUMA09 55.9+69 418.412.53vB;vL;vmE(ray)10.5 m5.1 mM 94GALXYCVN12 50.9+41 078.213.13vB;L;iR;vsvmbM;BN;r12.3 m10.8 mM 106GALXYCVN12 19.0+47 188.413.64!;vB;vL;vmE0;sbMBN17.4 m6.6 mM 51GALXYCVN13 29.9+47 128.412.94!!!;Great spiral nebula10.8 m6.6 mM 63GALXYCVN13 15.8+42 028.613.34vB;L;pME120;vsmbM;BN12.6 m7.5 mM 77GALXYCET02 42.7-00 018.912.84vB;pL;iR;sbMrrN7.3 m6.3 mNGC 2903GALXYLEO09 32.2+21 30913.64cB;vL;E;gmbM;r;sp of 212 m5.6 mNGC 3115GALXYSEX10 05.2-07 438.911.94vB;L;vmE 46;vgsmbMEN7.3 m3.4 m

These are the brightest galaxies so work your way down from the top. However not all are visible all night. You should do most of these with a dark sky and an 80mm scope.

Enjoy

Mark

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Ah, but it doesn't work like that! Close one eye and things don't become perceptibly less bright. However, I have never read a comptetent explanation of how doubling your lenses does affect apparent brightness. The effect is very disappointing in terms of what you can see. Again, close one eye when using bins. Remarkably little happens!

Andromeda (M31) is in fact visible naked eye at a dark site. My indifferent-to-poor 57 year old eyes can see it easily as a tiny elongated streak like a stretched star. We have a very low grade 80mm used as a finder on a big scope and that does get to many, many galaxies from this site including a host of NGCs.

Galaxies like to be seen near the zenith if possible because they need contrast and show best away from the inevitable sky glow.

Olly

On page 20 of this report CLICKY it says 100mm binoculars have combined area of aperture equal to a 141mm telescope?? Don't know how true this is.

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