Two from Sculptor

[madbadgalaxyman (Robert)]

Originally Posted by jase

Hi Robert,
Thanks for the supplemental information. I was not aware of the Gemini South image, WOW! I've thoroughly enjoyed reading through the detailed explanations and citations you have presented. It has allowed me to see the image from a completely different perspective. Thank you.

Jase,

Your image was well worth a couple of days of analysis.
You imaging blokes struggle mightily to get your images, so it is only fair that someone looks for unusual structures in them!

Mine is undeniably the easier job;
after all, all I have to do to find really weird things in galaxies is to look at lots and lots and lots of galaxy images. On the other hand, those years that I spent comparing and contrasting many 10s of thousands of galaxy images , have given me a very keen eye for peculiarities and anomalies in galaxies!

While it is slightly disappointing to both of us that the "yin and yang"/dual/dichotomy spiral structure of galaxies is not actually a new discovery, the length and the small opening angle of the old stellar spiral is remarkable, as is the fact that both old and young structures can be seen without resorting to Near-infrared imaging of the sort I referred to in my analysis.

Best Regards,
Robert Lang

It is definitely true that your galaxy has no single unique Hubble type!!!
It actually has a contradictory Hubble type;
something like Sa/Sc

(actually, I need to have a more detailed look at how this galaxy should be classified!)

[astronobob (Bob)]

Just looked through your web page Jason to find out what gear you have, wowsers, makes mine look like it was from Toyworld
Real nice Images by the way, M33 looks rather 3D too,

[jase (Jason)]

Thanks Robert. I'd be interested to know the final classification given the galaxy's complex nature once more information comes to hand.

Originally Posted by astronobob

Just looked through your web page Jason to find out what gear you have, wowsers, makes mine look like it was from Toyworld
Real nice Images by the way, M33 looks rather 3D too,

"Once you start down the dark path, forever will it dominate your destiny, consume you it will." - Yoda
A concise statement but captures the essence of astro imaging. Addictive and consuming. Personally, I'm not interested in the gear. Its just a means to getting data. I get more pleasure out of processing. Each to their own I guess.

[madbadgalaxyman (Robert)]

Originally Posted by jase

Thanks Robert. I'd be interested to know the final classification given the galaxy's complex nature once more information comes to hand.

I would like to send a link to your I5332 image, to Professor Ron Buta (Univ. of Alabama), who is a leading authority on galaxy classification.
(the Science Forum contains a link to his recent comprehensive review of galaxy morphology)
But it is hard to know if there would be enough interest among the "pros" to make a serious study of this galaxy. Its morphology is distinctive, but not absolutely unique.

One probably shouldn't get too obsessed with assigning a single Hubble class/type to each galaxy, as so many specific galaxies do not exactly correspond to a specific Hubble type.(for instance, there exist smooth-armed spiral galaxies that have a small bulge)

Hubble classes are essentially a convenient shorthand for describing, in a rough and ready way, what sort of galaxy we are talking about. However, within each Hubble type, there is a very large range of galaxy morphologies.

IC 5332 is in fact a good example of a galaxy that cannot readily be assigned a single unique type within the orthodox Hubble Sequence
(E - S0 - S0/a - Sa - Sb - Sc - Scd - Sd - Sm - Irr)

The inner spiral structure (quiescent ; yellow ; smooth ; two-armed) would in fact be more typical of an Sa galaxy.
In contrast, the more outer spiral structure (strongly star-forming ; blue ; entropic ; multiple-armed) corresponds much more to that which you would find in a galaxy that is later in the Hubble Sequence, perhaps a galaxy of type Sd.

So the template of a single Hubble class (type) is not very useful in the case of this galaxy;
it is a case of "either this type, or that type, or, more properly, both types".
Strange, but true!
As Obi Wan Kenobi said "these are the truths that we must cling to, Luke".

cheers, Mad Galaxy Man