Urban Galaxies

M31, M32, & M110 by Richard ArendtFor urban astronomers, galaxies are consistently disappointing. Galaxies that are stunning from a dark-site can be stubbornly invisible in even mildly washed-out skies. A very slight loss of contrast is enough to hide spiral arms, dark lanes and any other structural details. What makes galaxies even more frustrating is that none of the usual tricks for enhancing contrast work on them. Because they are extended objects with low surface brightness, increasing magnification just makes their already faint and diffuse light even more diffuse and fainter. Because galaxies radiate primarily stellar light, narrowband filters which can be very effective on emission and planetary nebulae don’t help at all with galaxies. So what’s an urban astronomer to do? Just give up on galaxies? Well, luckily there are a few galaxies that can be reliably seen under washed-out skies...

(Photo of M31 by Richard Arendt.)

The Top Urban Galaxies

Below are a handful of galaxies that will be relatively easy to find and see from urban and suburban areas in the northern hemisphere. But don’t expect to see anything beyond a faint fuzzy object with no detail. In fact, about the only features you’ll be able to distinguish is whether they are elongated or roughly circular, and the sharpness or diffuseness of the core.

I also want to highlight that transparency is really important when trying to observe galaxies. You are already handicapped in urban areas by the light-pollution. Add poor transparency on top of that, and even the Andromeda can be hard to see. So be sure to check the transparency forecast before you go galaxy hunting in washed-out skies. You can check the transparency forecast for your location using the fantastic Clear Sky Chart.

M31, the Andromeda Galaxy

Even in urban areas, you can see M31 as a hazy spot in 7x50 binoculars. In small telescopes, the core is clearly visible as a bright fuzzy oval that is brighter toward the center and fades out to an indistinct edge. Precisely how big the core looks will depend on both the light pollution and your aperture. In a 4 inch (100mm) scope in 3.5 magnitude skies, you might see an oval about 20' across. With a 10 inch (250mm) scope, you’ll see something maybe twice as big. But don’t expect to see anything larger than that, or to see any of the dust lanes that show up beautifully in photographs. In fact, under washed-out skies, M31 most resembles a large unresolved globular cluster.

Below on the left is a photograph of M31 by Richard Arendt.  The view is similar to what you might see in washed-out skies with a moderately sized telescope (8 inch (200mm) aperture or better). On the right I've altered his photograph to show what you might see under washed-out skies with a small telescope (4 inch (100mm) aperture or smaller). M32 is visible at the lower edge of both photographs.

Photograph of M31 & M32  by Richard Arendt shows what you might see with a moderately sized scopePhotograph of M31 & M32 by R. Arendt altered to look like what you can see in washed-out skies with a small scope

M32, satellite of the Andromeda Galaxy

While you are observing M31, you can also catch M32, a small elliptical galaxy that is M31’s brightest satellite galaxy. Compared to M31, M32 has a very bright small core that can look almost like a star. This means that you can see M32 even with small scopes in heavily light polluted skies. The challenge with smaller scopes in urban areas is that you can mistake M32’s nearly-stellar core for a star. If the night is reasonably transparent, a little use of averted vision with even a 3 inch (75mm) aperture is enough to show fuzziness around M32’s core.  Using a bit of magnification will help you confirm that it's M32 and not a star.

M32 appears near the bottom edge of the above photographs of M31. M32 is in the 6 o'clock position:  as you can see, it almost looks like a star.

M81, Bode’s Nebula

This spiral galaxy in Ursa Major is very bright and has the advantage of riding high the evening sky during the spring and early summer. Observe it near zenith on a night with decent transparency, and M81 shows up quite distinctly in 4 inch (100mm) apertures. The bright core is clearly non-stellar and a fainter area surrounding the core is also visible (perhaps with a bit of averted vision). The core is not quite round, and fainter area is clearly oval in shape, although it may take a bit more aperture to make out the shape. This is my favorite galaxy to show visitors, both because you can see it quite reliably in washed-out skies and in my 10” (250mm) Dob the “classic” oval shape is easily visible to even newbies (and the view fits their preconceived idea of what a galaxy looks like).

Of note, nearby M82 is much more sensitive to light-pollution and transparency than M81. On those "perfect" nights, M82 can be seen as distinctly as M81, but on less than perfect nights it can take an experienced eye and much use of averted vision to see it, even though M81 remains easy to see.

The photograph below of M81 by Richard Arendt closely resembles what you can expect to see visually in washed-out skies. In fact, you may see more: even from my light-polluted front yard, my 10'' (250mm) relfector generally shows a bit more of M81 than this photograph shows.

Photograph of M81 by Richard Arendt

M94, Croc’s Eye Galaxy

A rather bright spiral galaxy that also rides high in the evening sky in spring and summer, M94 is easy to see in 4 inch (100mm) apertures. It has a rather bright, tight core that is not quite stellar but closer to stellar than M81’s. Anything beyond the bright core of M94 is a bit hard to see but may be faintly visible in washed-out skies if the transparency is good. M94 is harder to find than M81 because there are few stars in the immediate area to use for star-hopping. But the core is bright and non-stellar enough that if you aim your scope half-way between Cor Caroli (α CVn) and Chara (β CVn), and then sweep northward perpendicular to the line between the two stars, you’ll invariably find it about 1.5 degrees away.

Below on the left is a photograph of M94 by Richard Arendt.  On the right I've altered it to better reflect what you might see under washed-out skies.

Photo of M94 by Richard ArendtPhoto of M94 by Richard Arendt altered to show what you might see under washed-out skies


Yet another bright galaxy that rides high in the sky during spring and summer evenings, M106 is a barred spiral that has a bright, oval-shaped core that is quite distinct (the infamous inner “ring” you will see mentioned in articles about M106). In urban areas, you won’t see anything beyond the core. M106 is a Seyfert II galaxy, with an unusually active core, especially in x-ray emissions. I normally find M106 by star-hopping from Phad (γ UMa) via 5 CVn and 3 CVn.

Below on the left is a photograph of M106 by Richard Arendt.  On the right I've altered the photograph to better reflect what you might see under washed-out skies.

Photo of M106 by Richard ArendtPhoto of M106 by Richard Arendt modified to show what you might see under washed-out skies


This is elliptical galaxy is the brightest member of the Virgo cluster. M49 It is a rather bright oval of light that gets brighter towards the center but doesn’t have a distinct core. It is located a bit south of central body of the Virgo Galaxy cluster. You can find M49 by an easy star-hop from Vindemaitrix (ε Vir). There are several other galaxies in the vicinity, but they will be challenging to see from an urban area.

The photograph below of M94 by Richard Arendt closely resembles what you can expect to see visually in washed-out skies.  

Photograph of M94 by Richard Arendt

M87, Virgo A

M87 is a supergiant elliptical galaxy that may have as much as 200 times the mass of the Milky Way. It is also a prominent radio and X-ray source. M87 continues to be the focus of many research efforts because it is ejecting a jet of matter at nearly the speed of light. This jet appears quite distinctive in photographs, but is invisible to the eye (although Otto Struve reportedly saw it visually using the 100 inch (2.5m) Hooker telescope at Mt. Wilson). Using small telescopes from urban areas, M87 appears as a bright, circular fuzz of light that is brighter towards center, but without a distinct bright core. M87 is an easy star-hop from Vindemaitrix (ε Vir), and the area around M87 has several other galaxies that you will have a reasonable chance of seeing from urban areas. M60 (to the east) and M84 (to the west) are the brightest of these.

The photograph below of M87 by Richard Arendt closely resembles what you can expect to see visually in washed-out skies. 

Image of M87 by Richard Arendt




I think M82 is worthy of inclusion in your top 10. Even under light polluted skies, it shows more detail than M81, even if the overall brightness is less.

M82 vs. M81

 In my experience, M82 is much more sensitive to light-pollution and transparency than M81, so sensitive that I can't really see it under light-polluted skies.  That's why I omitted it.

M82 vs. M81

From Central London, I find it is a lot easier to see M81 than M82. I think even though the overall magnitude is less, the angular size of the object is also less, so the constrast with the light polluted background is actually more. However I am willing to admit that at this stage, I don't really know what I am doing.


Southern hemisphere list

Thanks for this useful list, but do you have a list for the Southern hemisphere please?

Southern hemisphere list

Sorry, never had a chance to observe from the southern hemisphere. If you pay my travel, I'll gladly observe there and provide a list :)

very dissapointed

Thank you for your review about to expect to see from my urban location when it comes to galaxies. I am very dissapointed :( I was hoping that a 11" SCT would let me see spirals, tails, more details of galaxies but looks like a smushed of little dots.

Is there any telescope size or type that would let me experience amazing details from an urban location with red pollution? (white being worst, red second worst, orange next, etc)


Galaxies in a red zone

I'm sorry, but I doubt very much any size telescope will let you see those kinds of details from a red light-pollution zone. That larger aperture is not only collecting more light from the galaxies, it is also collecting more background light pollution. To the extent that you can use more magnification with a large aperture, you can use the higher magnification to improve contrast a bit. But I doubt very much you'll ever get the kinds of views you are looking for.

On the other hand, take your 11 inch SCT out to a dark site and you'll see some spectacular details in galaxies like M51, M33, M101, and M104.

Same With Orange Zone

I live in an Orange Zone and have the same problem.

Urban Skies-Light Pollution.

I live over in NW London, home to Flight paths, light pollution and security lights.
That said, I am happy with the images I get of the brighter galaxies and better results
can be achieved with narrow band imaging. Don't be put off!
I also use light pollution filters in front of the cameras which help with the longer exposures.
Good luck and clear skies.
PP London Astronomer