Galaxy observing

[acey]

 that's not true at all M51 will show spiral structure  form a moderate dark sky with a 8inch scope. m31 is just so big and is nearly side on so you don't really see much detail in m31, if m31 was face on like m51 it would be one of the best galaxies to observe.

Would you care to define "moderate dark"?

I fully agree that it is perfectly possible to convince oneself that one has seen the spiral structure of M51, even under conditions where actual visibility is almost impossible. The bridge between M51 and its companion is a case in point: plenty of people think they have seen it as a continuous band connecting the galaxies. To which I can only say: look with the eye, not the imagination.

If M31 were face on it would indeed be a magnificent sight. Instead we must content ourselves with M33, whose spiral arms have about the same surface brightness that those of M31 would have. In other words, we would have a lot of people complaining that at a site with SQ < 20, M31 would be a big bright featureless blob (the central bulge), while others would reassure them that the spiral arms could be easily seen at a site with SQ > 21.

As it is, M31 shows more detail than just about any other galaxy - if the sky is dark enough.

[DazC]

Get yerself to mid wales Steve gonna be a lot of dobs there soon!

Dob fest?

D.C

[Daniel-K]

Would you care to define "moderate dark"?

I fully agree that it is perfectly possible to convince oneself that one has seen the spiral structure of M51, even under conditions where actual visibility is almost impossible. The bridge between M51 and its companion is a case in point: plenty of people think they have seen it as a continuous band connecting the galaxies. To which I can only say: look with the eye, not the imagination.

If M31 were face on it would indeed be a magnificent sight. Instead we must content ourselves with M33, whose spiral arms have about the same surface brightness that those of M31 would have. In other words, we would have a lot of people complaining that at a site with SQ < 20, M31 would be a big bright featureless blob (the central bulge), while others would reassure them that the spiral arms could be easily seen at a site with SQ > 21.

As it is, M31 shows more detail than just about any other galaxy - if the sky is dark enough.

sorry I still disagree m31 is pretty much a simple galaxy at best will show you some dark dust lanes even from a site with SQ20 where as the likes of M33 & 101 will show you everything they have to offer from spiral arms to singing HA regions. I observe from the some of the darkest places in the uk and m31 hardly shows anything but the likes of m51 31 & 101 will show you heaps more.

moderate dark our local hot spot 30 mins drive from the city will show you spiral structure and the interacting galaxy in 51  on a moonless night. NELM APPROX 6.

aperture is king when it comes to galaxies.

[sonic190178]

Would you care to define "moderate dark"?

I fully agree that it is perfectly possible to convince oneself that one has seen the spiral structure of M51, even under conditions where actual visibility is almost impossible. The bridge between M51 and its companion is a case in point: plenty of people think they have seen it as a continuous band connecting the galaxies. To which I can only say: look with the eye, not the imagination.

If M31 were face on it would indeed be a magnificent sight. Instead we must content ourselves with M33, whose spiral arms have about the same surface brightness that those of M31 would have. In other words, we would have a lot of people complaining that at a site with SQ < 20, M31 would be a big bright featureless blob (the central bulge), while others would reassure them that the spiral arms could be easily seen at a site with SQ > 21.

As it is, M31 shows more detail than just about any other galaxy - if the sky is dark enough.

acey how much do you get out with your scope

m31 is the brightest galaxy but only under the very best conditions can you make out the globs in it

m101,51,33,81,82 because there face on are easier to make out structure

as for m51 not being able to see the bridge between them I would change your dark sky site,because  I have seen m51 like a image from wales in a 8" scope

[acey]

I observe in Northumberland, not far from Kielder, SQ 21.3 to 21.7. I've observed 2 of M31's globular clusters (with a 12"), as well as its star cloud NGC 206, and the intricate tracery of dust lanes that can be seen at moderate to high power. I've observed the spiral structure of M51 with 8" and 12", as well as spiral arms in many other galaxies (I've looked at nearly 2000 over the years). I've seen all the NGC star clouds and HII regions in M33 and M101. I've also enjoyed detailed views of DSOs with apertures as small as 50mm at dark sites in UK and abroad. The conclusion I have reached is that the most important factors are: sky darkness, sky transparency, observer skill/patience/motivation/preparation/education.

For DSOs, larger aperture almost always beats smaller aperture at the same site (the exception is on very large, very low surface brightness objects - ones that didn't get into the NGC).

But dark sky almost always beats lighter sky, no matter what aperture is used (the exception is objects that appear stellar, e.g. quasars, where a big scope at a bright site may be able to beat a smaller scope at a darker one).

And averted imagination is a thing we all fall victim to at times, me as much as anyone (especially when I was less experienced, and more likely to look at images before first observing a target, rather than after).

Just my two penn'orth. But as well as being borne out by personal experience, my remarks are supported by scientific research, as can be seen in this paper, where Figure 18 shows the superiority of a 6" scope at a dark site (SQ 21.5) over a 16" at a light-polluted one (SQ 20).

http://arxiv.org/abs/1405.4209

Aperture is indeed king, but only as long as sky darkness is held constant. If sky darkness is a variable then that is the supreme ruler.

[greglloyd]

Would you care to define "moderate dark"?

I fully agree that it is perfectly possible to convince oneself that one has seen the spiral structure of M51, even under conditions where actual visibility is almost impossible. The bridge between M51 and its companion is a case in point: plenty of people think they have seen it as a continuous band connecting the galaxies. To which I can only say: look with the eye, not the imagination.

If M31 were face on it would indeed be a magnificent sight. Instead we must content ourselves with M33, whose spiral arms have about the same surface brightness that those of M31 would have. In other words, we would have a lot of people complaining that at a site with SQ < 20, M31 would be a big bright featureless blob (the central bulge), while others would reassure them that the spiral arms could be easily seen at a site with SQ > 21.

As it is, M31 shows more detail than just about any other galaxy - if the sky is dark enough.

I've seen M51 through a 16" scope and the spiral structure was entirely obvious with direct vision. No imagination required! However, at apertures of below 12" I agree that some of what you may think you see is from memory of images you've seen. Although on the best of nights, I think a 10" scope can certainly begin to show you stuff in M51 that is not from imagination.

[mdstuart]

Try this...

http://stargazerslounge.com/topic/95124-galaxies-for-seeing-structure/

[acey]

No question that M51 spiral arms can be seen with an 8" at a dark site - I've done it many times. The bridge between the galaxy and its companion is another matter. I thought I'd seen it with the 8" - until I viewed with 12" and realised that the mind (or imagination) fills in the gap. Not saying it can't be seen - just that it can easily be imagined.

[greglloyd]

You definitely need to factor in the power of the mind when observing galaxies. I tend to use techniques such as nudging the view and repositioning the galaxy in the field of view to try and avoid my mind filling in any potential gaps. The M51 bridge is definitely an example of something you might 'want' to see - whether it is really there or not.

[swamp thing]

It would seem we can all agree on one thing.......galaxies are more visually than fuzzy blobs

I'm not going to suggest what's the best visually that's up to each and every observer but this thread shows that galaxy observing is far from just fuzzy blobs. Get out to dark skies and make your own minds up.

Have fun out there

[estwing]

It's funny how the mind fills in the blanks while viewing......Ban AP I say!!!

[bomberbaz]

Yes thanks everyone. My question is well answered and as expected dark skies are the way to go. Anyway as mentioned in 3 weeks i will be in galloway at the adtronomy centre and skies permitting, galaxy viewing will be on the agenda.

Steve

[greglloyd]

One thing I tend to do is to avoid looking at any pictures of an object I plan to view in the day or days beforehand. I then spend time at the eyepiece trying to see detail and then cross reference against a photo only afterwards.

[John]

One thing I tend to do is to avoid looking at any pictures of an object I plan to view in the day or days beforehand. I then spend time at the eyepiece trying to see detail and then cross reference against a photo only afterwards.

Thats the way I do it too. It's all to easy for "averted imagination" to creep in.

[Moonshane]

I once showed someone the Pacman Nebula and they said at the time 'I cannot tell if I am seeing it or remembering it'. Quite an apt description I feel.

[bomberbaz]

I once showed someone the Pacman Nebula and they said at the time 'I cannot tell if I am seeing it or remembering it'. Quite an apt description I feel.

I think you signature says it all shane, "don't think it, feel it"