Quote:
Originally Posted by Ken Crawford
Very Cool! Thanks for pointing this out as it makes what I saw in the processing easier to understand! I have always looked at imaging processing like space exploration as if you dig deep enough you sometimes see things you have not seen as well before. The slight warp to the galaxy shows a past interaction and I did look for star streams in the data but could not find any.
Thanks again for posting the interesting data on this amazing galaxy.
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Hello Ken,
The grainy old chemical-process images in the Carnegie Atlas of Galaxies were useful for a rough and ready analysis of three-dimensional structures found within galaxies, but
high resolution amateur CCD imaging such as yours can definitely shed much more light on the details of the morphology. (not the least because of the much greater dynamic range)
I am glad you found the Spitzer 8 micron view to be interesting!
Here is an NIR view from 2MASS. This image is shortwards of 3 microns, so what is being detected in this image is nearly all
stellar light rather than gas and dust. The narrowness of the dust lane in front of the bulge is very evident, as is an interesting central concentration of light (or circum-nuclear feature) that is nested within the larger bulge.
Both the narrow dust lane and the central morphological feature are evident in your image, but they are more obvious in this Low Extinction near-infrared regime:
"Just for fun and profit", I also attach the Far Ultraviolet + Near Ultraviolet image from GALEX. This looks decidedly odd, but some of the asymmetry may be due to variations in the very strong extinction of ultraviolet light by dust.
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I will see if I can dig up some more enlightenment about this galaxy from a couple of recent infrared papers about it. I have got some hunches about N4565, but I think I really need to overlay some images at various wavelengths.
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Note added in later edit:
And look how
boxy the bulge is, especially in the near-infrared image......these "bulges" are sometimes not real bulges (that is, spheroids), but instead are actually
bar structures that are seen edge-on. It may be that N4565 is much later in the Hubble Sequence then we think it is, as this may not be a real bulge, but instead a pseudo-bulge.
There are various gradations found in galaxies between a genuinely spheroidal bulge (which is
oblate spheroidal in shape), and a bar, and a "weak bar" which is just a slightly elongated bulge ("hot dog bun" shaped).
Our own Milky Way has a bulge which is also a weak bar, so this is sometimes called a "Bulge/Bar", just to confuse things further.
Added in a Second edit:
Madbadgalaxyman's puzzlers of the day:
Could the boxy "apparent bulge" that we see in our two-dimensional (flat) images be simply a
bar that is seen edge-on, and
not a spheroidally-shaped bulge?
Could the very-compact spheroidal structure that is nested within this "pseudo-bulge" be the
real bulge of this galaxy?
Are we actually looking at a galaxy with a very very small bulge?
) ......
