Minimum scope to see galaxy spirals

[jetstream]

I was wondering what size/type of scope would be needed to see the spirals in galaxies?I have seen the Andomeda galaxy so far with my set up in good seeing.I'm curious to here how others have done with their setups.

[Sam]

I have seen the spirals in M51 in an 8" reflector.

[zoneca]

I have 12" dob but haven't seen any galaxy yet... lol

Jon.

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SW 12" dob f/4.9 - Plossl 25mm, 10mm 1.25".

[Stu]

Not sure what the minimum would be, but galaxies are far more about dark skies than scope size. Any LP just washes them out as they are faint, so get yourself (and your scope!) under a dark sky whenever you can.

Stu

[rory]

id say alot is always going to depend on the conditions to be honest. ive never seen arms of a galaxy with my 8" newt ,but i do my observing from my back garden within a light polluted area.

now if i looked through an 8" from a very dark site ,i see much much more.

most reports i read from the forums,id suggest 12" aperture is where it becomes more common to see structure.

[rory]

those pesky double posts .

[ollypenrice]

We have a 20 inch at an extrememly dark, elevated site. The spirals of M51 can be very clear when the object is at high elevation so, even with this setup, conditions need to be good. Dust lanes in Andromeda are dramatic. Again when it's high up M101 shows clear but faint spiral structure and bright patches at the ends of two opposing spiral arms.

Olly

[ursamajorro]

I have seen the spirals in M51 in an 8" reflector.

I confirm this. Using my Skywatcher Black Diamond 200/1000 I managed to see easily spiral arms at Whirlpool Galaxy (M51) and Pinwheel Galaxy (M101).

[Schorhr]

With 5.1" I can see faint bits of structure on m51, but nothing obvious. Even with 6" it should be difficult to really make out anything spiral-y ;-)

Check out http://www.clarkvision.com/visastro/m51-apert/index.html but keep in mind you will need dark conditions, practice, and observe several minutes to adapt to the darkness, and then several minutes to really see all the details.

Also m51 is really one of the brighter objects, keep in mind some objects are difficult in even larger telescopes.

there are sensitive cameras to amplify during observation and will show speaks when in small telescopes but they cost more then a telescope itself...

I still use my 5.1" telescope as it needs no setup and is light. Even if you can only see the shape of galaxies with little to no structure it still outs Ann amazing experience.

With the 10" Sumerian optics travel dobsonian I will have to find a dark site to really benefit from the aperture. But even it's 9 kg are the maximum I am willing to carry around :-) and regular dobsonian are much heavier so you either have to have a remote place or drive a lot to flee from light pollution...

[John]

I've seen spiral structure in Messier 51 with 10" and 12" scopes at a reasonably dark site. The 12" will just about show it from my back yard but not as well as the dark site does. Under really dark, transparent skies I guess an 8" or even a 6" might suffice.

I've not, so far, been able to pick our clear spiral structure in other galaxies although M31's dust lanes are possible on a good nights.

The seeing conditions / light pollution / transparency levels make a huge difference to the detail you will see in galaxies.

[Luke]

I've seen see a decent amount of faint spiral structure in M51 when it's high up, under okay skies using a 10 inch dob.

[oldfruit]

Using my 12 inch dob at our dark site on the Lincolnshire coast, it is possible to see a lot of structure in M51, including the spiral arms and lighter and darker patches. Though you do need to spend a fair bit of time at the eyepiece to tease out the extra detail.

As has already been said, the object being overhead and viewed from dark skies makes all the difference.

[jetstream]

Great response,it seems like a really dark site is one of the keys to observing these things,when I saw m31 & m110 I was in a remote very dark place,no clouds etc.I have looked for m51 but no luck yet-but just from my back yard.When conditions are right I will pack up & go "hunting" more seriously.I don't expect to see spirals or detail,most likely one fuzzy blob,maybe both.Aperature sounds like an important feature to see more deatil as long as seeing is good.Does seeing have a huge impact on viewing galaxies and nebula?Out of the factors involved(transparency,cloud cover,humidity,darkness etc) which are the most limiting in viewing these objects?My location and terrain around here would make a Dob difficult to use,especially if seeing limits their effectiveness on DSO

[starbright]

I'd say light polution is the most important factor. I lived in Australia for 34 years and was a member of the Queensland Astronomical Society and the Astronomical Association Of Queensland. Both these bodies had dark sky sites which were 100 km from Brisbane on the east coast yet members with 16'' scopes had problems due to LP. On one visit to a small town further north called Tin Can Bay the sky was inky black and in fact, it's the only time I've seen the milky way in all its glory. Unfortunately I didn't take a telescope with me.

[jetstream]

I'm actually amazed at how much light pollution there is everywhere,it's a real eye opener.It influenced my choice of telescope but I still wonder about a Newtonian reflector.Somewhere on the web I saw a dark sky chart,our cabin is just on the edge of a true dark spot,but really to get to the area is 30-40 more km away,in the bush.I can get to the place on logging roads,but now the mosquitos and blackflies are coming out.The best views thru my small scope came from here,I can only imagine the view in a bigger scope.Because of my erractic weather here I just don't know if I would be able to use the light bucket with more effectiveness.From the cabin I can see the skyglow from my small town-looks like a glowing dome,unreal.So I have to decide if lugging a big scope into the bush is practical-will it hold collimation etc...

[planet15]

I drove home 60 miles with the TAL-1 in the back of my car, when I bought it 2nd hand, and collimation is fine. This reflector is made in 1993, so it has been around for good 20+ years, all is still good and the image is crystal clear.

When I bought the Skywatcher Skyliner 200P, it arrived after 300+ miles journey in a parcel van from down south. When it was assembled and set up, it gave crystal clear view. It didn't need collimation. It has been taken out from my shed, carryed back and forth to the end of the garden a few times so far, and it seems it will be OK for next 100 years.

[bish]

I've seen the slight hint of structure in m51 from a suburban garden with a 10" scope when it's overhead and conditions spot on. Not definitive spiral arms by any means. I've looked at m51 with the same scope from a very dark site when the galaxy was low down and conditions less than ideal and it was just a fuzz. Jealous of olly's set up and location!

[bingevader]

Using the Clarkvision comparison, with my 8" dob, I'd say more like the 6" mostly from my back garden.

Faint dust lanes in M31 on a good night.

Cheers

[Demonperformer]

Don't think you will see them visually with your scope, but I have found that taking quite short exposures with my canon on my 4" scope I can get some quite nice spiral structure in a single 20s sub. I guess it helps if you pick the right galaxy, but (one that hasn't been mentioned yet) the spiral nature of M61 showed up quite well.

[LukeSkywatcher]

Galaxies in my 5" Dob are "faint fuzzies" as to be expected. In my 8" SCT they are not much more really. It all boils down to local "seeing".

[jetstream]

It's good to here that a reflector can stand some "punishment" on the way to a site,I don't know how sensitive they can be.Maybe a guy should keep the F ratio up so the "sweet spot"(collimation wise) is bigger for a scope that will be drug around-F6 and higher?I'm envious of olley,john and the others who have seen the galaxy structure,I can't wait to join the club!For now I'll take the 90mm to the dark site to see what I can see,good baseline for me to compare to other scopes in the future.I would like to find someone around here with a 8-10" reflector just to take a peak.The astronomy club I joined has some experienced members-long way away though.In terms of reflectors,how do Newtonians and Cassegrains compare on galaxies and nebula?Given equal optics of course.I already have an interest in Newtonian reflectors,amazes me how astronomers hundreds of years ago figured out the technology to view the sky.