Starship Asterisk*

Most esoteric coffee mug ever.

You can see the different rotations in this image
http://s189.photobucket.com/albums/z159/BMAONE23/?action=view&current=M31_HALRGBpugh.jpg

Yes, that happens a lot on a lot of astrophotography. In this, they seem to change based on what quadrant they are in. I think it's caused by taking multiple exposures. He may have taken 4 shots of Andromeda in 4 quadrants. I never bothered looking into it too deeply so that's just a guess.

Geck,
I hadn't noticed that, But now that you mention it...I do notice something else about this curiosity, All the lateral bisection appears to change angels as you progress around the image and all form a circular structure surrounding the background galaxy.

They're all like that, B. It must be a quirk of the telescope's optics.

When viewing the full size image, there is a bright star in the upper left area (view image at full size not zoomed out) that appear to be bicected. Is something happening here or is it just a processing anomoly?

Which is larger the Milky Way or Andromeda? http://www.space.com/scienceastronomy/060221_stues_dark_matter.html
According to one study; Andromeda is larger but the Milky Way is more massive due to dark mater. :?

[quote="APOD Robot"][url=http://apod.nasa.gov/apod/ap100109.html][img]http://apod.nasa.gov/apod/calendar/S_100109.jpg[/img] [size=150]Andromeda Island Universe[/size][/url]

The most distant object easily visible to the eye is M31, the great Andromeda Galaxy some two and a half million light-years away. But without a telescope, even this immense spiral galaxy - [b]spanning over 200,000 light years[/b] - appears as a faint, nebulous cloud in the constellation Andromeda.[/quote]
[quote=" http://antwrp.gsfc.nasa.gov/diamond_jubilee/1920/cs_nrc.html"]

BULLETIN OF THE NATIONAL RESEARCH COUNCIL
Vol. 2, Part 3, May, 1921, Number 11, pp 171-217.
THE SCALE OF THE UNIVERSE
----------------------------------------------------------
_DIMENSIONS AND STRUCTURE OF THE GALAXY_ BY HEBER D. CURTIS
[img]http://antwrp.gsfc.nasa.gov/diamond_jubilee/1920/curtis.gif[/img]

<<I hold, therefore, to the belief that [b]the [Andromeda] galaxy is probably not more than 30,000 light-years in diameter[/b]; that the spirals are not intra-galactic objects but [b]island universes[/b], like our own galaxy, and that the spirals, as external galaxies, indicate to us a greater universe into which we may penetrate to distances of ten million to a hundred million light-years.>>
----------------------------------------------------------
_EVOLUTION OF THE IDEA OF GALACTIC SIZE_ BY HARLOW SHAPLEY
[img]http://antwrp.gsfc.nasa.gov/diamond_jubilee/1920/shapley.gif[/img]

<<[b]Another consequence of the conclusion that the galactic system is of the order of 300,000 light-years in greatest diameter, is the previously mentioned difficulty it gives to the "comparable- galaxy" theory of spiral nebulae ... Since the [island universes] theory probably stands or falls with the hypothesis of a small galactic system, there is little point in discussing other material on the subject...[/b]

It seems to me that the evidence, other than the admittedly critical tests depending on the size of the galaxy, is opposed to the view that the spirals are galaxies of stars comparable with our own. In fact, there appears as yet no reason for modifying the tentative hypothesis that the spirals are not composed of typical stars at all, but are truly nebulous objects. Three very recent results are, I believe, distinctly serious for the theory that spiral nebulae are comparable galaxies -

(1) Seares' deduction that none of the known spiral nebulae has a surface brightness as small as that of our galaxy;

(2) Reynold's study of the distribution of light and color in typical spirals, from which he concludes they cannot be stellar systems; and

(3) van Maanen's recent measures of rotation in the spiral M 33, corroborating his earlier work on Messier 101 and 81, and indicating that these bright spirals cannot reasonably be the excessive distant objects required by the theory.

But even if spirals fail as galactic systems, there may be elsewhere in space stellar systems equal to or greater than ours - as yet unrecognized and possibly quite beyond the power of existing optical devices and preset measuring scales. The modern telescope, however, with such accessories as high-power spectroscopes and photographic intensifiers, is destined to extend the inquiries relative to the size of the universe much deeper into space, and contribute further to the problem of other galaxies.>>
----------------------------------------------------------[/quote]

this is a beautiful post. i've always felt dissatisfied with andromeda images -- the nucleus always seems overexposed, the arms seem crooked somehow, and all the galaxy stars get in the way -- but pugh got the balance of color and luminance just right. the spiral structure is clear, the nucleus isn't on botox, the satellites look fluffy and magical; it's a work of art. also, kudos to apod for the balance between "amateur" and professional, or land and space observatory imagery. it's refreshing to see the variety and vigor of modern astronomical research.

the post to the shapley curtis debate was also interesting. i didn't realize andromeda had that historical significance. in fact i'd love to see more about this galaxy, which seems strangely underresearched or underreported given its size and proximity. the more we learn about it the more it resembles a twin sibling, not a big brother. it even has two "magellanic clouds"!

A good APOD. It is important to understand that it wasn't very long ago, our parent's and grandparent's time, that scientists did not believe that there were galaxies other than our own. They also did not believe that all matter was composed of tiny elements called atoms. Edwin Hubble, largely credited with associating the redshift with distance, took to his grave the belief that the universe was not expanding. Scientific knowledge and beliefs change, dramatically, over time.

[url=http://apod.nasa.gov/apod/ap100109.html][img]http://apod.nasa.gov/apod/calendar/S_100109.jpg[/img] [size=150]Andromeda Island Universe[/size][/url]

[b] Explanation: [/b] The most distant object easily visible to the eye is [url=http://www.seds.org/messier/xtra/history/m-m31_42.html]M31[/url], the great [url=http://www.seds.org/messier/m/m031.html]Andromeda Galaxy[/url] some two and a half million light-years away. But without a telescope, even this immense spiral galaxy - spanning [url=http://apod.nasa.gov/apod/ap061228.html]over[/url] 200,000 light years - appears as a faint, nebulous cloud in the [url=http://www.hawastsoc.org/deepsky/and/index.html]constellation Andromeda[/url]. In contrast, details of a bright yellow nucleus and dark winding dust lanes, are revealed in this [url=http://www.martinpughastrophotography.id.au/STXBeta.htm]digital telescopic image[/url]. Narrow band image data, recording emission from hydrogen atoms, shows off the [url=http://apod.nasa.gov/apod/ap091017.html]reddish star-forming regions[/url] dotting gorgeous blue spiral arms and young star clusters While even casual [url=http://badastronomy.com/bitesize/galaxies.html]skygazers[/url] are now inspired by the knowledge that there are [url=http://apod.nasa.gov/apod/ap070208.html]many[/url] distant galaxies like M31, astronomers [url=http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?1995PASP%2E%2E107%2E1133T]seriously debated[/url] this fundamental concept in the 20th century. Were these "spiral nebulae" simply outlying components of our own Milky Way Galaxy or were they instead "island universes" -- distant systems of stars comparable to the Milky Way itself? This question was central to the famous [url=http://antwrp.gsfc.nasa.gov/diamond_jubilee/debate20.html]Shapley-Curtis[/url] [url=http://antwrp.gsfc.nasa.gov/diamond_jubilee/debate.html]debate[/url] of 1920, which was later resolved by [url=http://apod.nasa.gov/apod/ap960406.html]observations[/url] of M31 in favor of Andromeda, [url=http://nedwww.ipac.caltech.edu/level5/March02/Gordon/Gordon2.html]island universe[/url].

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