Galaxy structure

[Nova2000]

Hi everyone. 

Galaxy season in the horizon. 

How many such galaxies are there of which one can see the details properly? 

I remember m51. I only looked at it for 5sec due to a rush during a star party. I didn't get time to study it tho. (i was in a separate team and there was a hunting competition  my team won it with a lead of 15 objects. Thanks virgo ) 

Which galaxies display a view of their structure other than  a smudge if light? 

Scope is a skywatcher 150/1200 reflector. I have 40mm,25mm and 10mm eyepiece. Also a 20.

I would be happy if you'll can recommend me some more bright galaxies to observe 

Clear skies 

Rajesh 

 

 

[michael.h.f.wilkinson]

Very few galaxies show clear structure, and only then when conditions are really good. Aperture only shows more detail when the skies are really, really dark. I have spotted spiral structure in M33, M51, M81, M101, and a few others with modest scopes (M33 even shows it in my 80mm), but only from dark sites. From a very dark site in southern France, my 8" SCT shows more detail than our university 16" RC from the city (daft place to put such a scope). Of course, from a dark site, a 20" Dobson shows AMAZING detail.

[John]

M82 shows interesting dark rifts across it in quite modest apertures, if the skies are dark and transparent.

The darker and more transparent your skies, the more galaxies will show some structure.

[Nova2000]

39 minutes ago, michael.h.f.wilkinson said:

Very few galaxies show clear structure, and only then when conditions are really good. Aperture only shows more detail when the skies are really, really dark. I have spotted spiral structure in M33, M51, M81, M101, and a few others with modest scopes (M33 even shows it in my 80mm), but only from dark sites. From a very dark site in southern France, my 8" SCT shows more detail than our university 16" RC from the city (daft place to put such a scope). Of course, from a dark site, a 20" Dobson shows AMAZING detail.

Which University are you talking about Micheal?  The local club would have taken a c14 to the dark sky but unfortunately it doesn't work! Mount problem

[michael.h.f.wilkinson]

19 minutes ago, Nova2000 said:

Which University are you talking about Micheal?  The local club would have taken a c14 to the dark sky but unfortunately it doesn't work! Mount problem

I work at the University of Groningen. The 16"RC is mounted permanently in a dome atop our building

[Nova2000]

Does humidity affect observing conditions? 

[michael.h.f.wilkinson]

1 hour ago, Nova2000 said:

Does humidity affect observing conditions? 

Generally: yes. Apart from fogging up the corrector plate of an SCT, I find humidity tends to cause problems for DSO observation, possibly by slightly reducing transparency, and causing increased back-scatter of city lights. Effectively, high humidity often means a very light haze.

[ollypenrice]

28 minutes ago, michael.h.f.wilkinson said:

Generally: yes. Apart from fogging up the corrector plate of an SCT, I find humidity tends to cause problems for DSO observation, possibly by slightly reducing transparency, and causing increased back-scatter of city lights. Effectively, high humidity often means a very light haze.

I entirely agree. I live at a dark site but nowhere in mainland Europe is totally dark down to the horizon. What we see here is that in really dry air the very distant light pollution rises only about 8 degrees above the horizon. The damper the air above the sources of LP, the more it rises - sometimes to about 20 degrees or even a little more.

I find that spiral structure, even in a big Dob, needs the air to be dry and transparent and the object needs to be as high as possible in the sky. This makes an enormous difference.

On the other hand somewhat humid air can be the best of all for high powered planetary observation. A little haze seems to be associated with very stable air.

Olly