APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep 25)

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Expand view Topic review: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep 25)

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by starsurfer » Wed Oct 01, 2014 6:40 am

geckzilla wrote:I do not need hugs! I need data! Raw, pristine, ugly data!
I'm of the opinion that you need a hug but apparently my detector is faulty. Some more time is what I need, there isn't enough time for astronomy related things! :cry:

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by geckzilla » Wed Oct 01, 2014 6:36 am

I do not need hugs! I need data! Raw, pristine, ugly data!

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by starsurfer » Wed Oct 01, 2014 6:34 am

geckzilla wrote:After further consideration I have decided that the post above this is almost complete crap and that I know nothing. Nothing! :bang:
I wholeheartedly agree with you concerning diffraction spikes! :D
Want a hug to cheer up?

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by geckzilla » Wed Oct 01, 2014 6:21 am

After further consideration I have decided that the post above this is almost complete crap and that I know nothing. Nothing! :bang:

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by geckzilla » Fri Sep 26, 2014 7:06 pm

Chris Peterson wrote:
starsurfer wrote:You've asked me this before in the past and as I've said previously, I have an inbuilt fake diffraction spike detector.
Yes, your detector seems quite good. I wasn't sure about this one because there are obviously real spikes and real diffraction effects still present in the image.
I think it's easy to tell which ones are real and which are generated and which are real when they are long enough. Short ones don't provide enough detail but when they are very long, some banding (is this an Airy pattern?) should be visible in each wavelength and I presume the only time this pattern would be hidden is if multiple broadband sources are combined into a single channel (or a wide enough section of the continuum?). Since the spikes themselves in this image come in various colors rather than monochrome, then I would like to confidently say that they are fake, even without input from Robert (or whomever's image happens to be in question) and without simply resorting to the argument that they don't look real to me personally "because of the pixels".

I do think that some diffraction spikes could be simulated in a way that makes them nearly indistinguishable from real ones. There also remains the possibility that real diffraction spikes can be mistaken for fake ones depending on the processing. The former would probably require some serious dedication without a lot of benefit or purpose. The latter probably happens by accident. So, for now, I think it is possible to make the distinction based on this sort of evidence with a fair amount of certainty.

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by geckzilla » Fri Sep 26, 2014 3:27 pm

starsurfer wrote:Judy Schmidt is one of the nicest people in the world and its great to see collaborations!
Your nice person detector is broken, though.

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by Chris Peterson » Fri Sep 26, 2014 2:00 pm

starsurfer wrote:You've asked me this before in the past and as I've said previously, I have an inbuilt fake diffraction spike detector.
Yes, your detector seems quite good. I wasn't sure about this one because there are obviously real spikes and real diffraction effects still present in the image.

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by starsurfer » Fri Sep 26, 2014 10:29 am

Chris Peterson wrote:
starsurfer wrote:However, I'm not a fan of the fake diffraction spikes.
Are you sure they're fake? All the datasets were collected with instruments that produce diffraction spikes, and some brighter stars show spikes on more than one axis. Are you suggesting that the original spikes were edited out and then new ones synthesized? Certainly, the scatter discs around bright stars looks real.
You've asked me this before in the past and as I've said previously, I have an inbuilt fake diffraction spike detector. :D
rgendler wrote:I want to thank Judy Schmidt for her help with today's APOD. She made me aware of the great NOAO local survey data which I used to revise my older version of the same field.
Judy Schmidt is one of the nicest people in the world and its great to see collaborations!

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by Ann » Thu Sep 25, 2014 11:49 pm

starsurfer wrote:I have never seen an image of the Andromeda Galaxy that shows its ionized content this well! Rob Gendler is amazing and is one of the few people on this planet that is truly legendary! However, I'm not a fan of the fake diffraction spikes.
Well spotted, starsurfer.

And thank you for the fine explanation, Rob! Indeed, combining exposures from different telescopes into a single natural-looking image must be a huge challenge.

Ann

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by hlwelborn » Thu Sep 25, 2014 11:34 pm

This is very familiar. I think I grew up near here.

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by rgendler » Thu Sep 25, 2014 6:37 pm

I want to thank Judy Schmidt for her help with today's APOD. She made me aware of the great NOAO local survey data which I used to revise my older version of the same field.

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by rgendler » Thu Sep 25, 2014 6:04 pm

Chris Peterson wrote:
starsurfer wrote:However, I'm not a fan of the fake diffraction spikes.
Are you sure they're fake? All the datasets were collected with instruments that produce diffraction spikes, and some brighter stars show spikes on more than one axis. Are you suggesting that the original spikes were edited out and then new ones synthesized? Certainly, the scatter discs around bright stars looks real.

Yes.....some of the brighter stars have artifactual spikes. Combining very disparate data like Subaru and amateur data often produces very ugly stellar artifacts so at the time I made the first version (last year) I was experimenting with Neil Carboni's star tools and used it to make some cosmetic adjustments on the brighter stars. Perhaps I should have stated this on my web page.

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by LocalColor » Thu Sep 25, 2014 5:00 pm

Another beautiful APOD - thanks.

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by Chris Peterson » Thu Sep 25, 2014 3:04 pm

starsurfer wrote:However, I'm not a fan of the fake diffraction spikes.
Are you sure they're fake? All the datasets were collected with instruments that produce diffraction spikes, and some brighter stars show spikes on more than one axis. Are you suggesting that the original spikes were edited out and then new ones synthesized? Certainly, the scatter discs around bright stars looks real.

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by dmathew1 » Thu Sep 25, 2014 2:27 pm

Wow! I'd love to see a full resolution picture of the Andromeda galaxy on a video wall. Either that, or wait four billion years and see Andromeda when it begins to fill the Earth's night sky.

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by Boomer12k » Thu Sep 25, 2014 10:11 am

Awesome close up...

Awesome amount of stellar formation places.

I WONDER how many we could name...if we were over there.... 8-)

I wonder if OUR PROXIMITY has any effect on the star forming....because someday...I am thinking...we are BOTH going to be Star-burst Galaxies...as we get closer and closer.

:---[===] *

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by starsurfer » Thu Sep 25, 2014 7:05 am

I have never seen an image of the Andromeda Galaxy that shows its ionized content this well! Rob Gendler is amazing and is one of the few people on this planet that is truly legendary! However, I'm not a fan of the fake diffraction spikes.

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by Mactavish » Thu Sep 25, 2014 5:51 am

Another outstanding contribution by Robert Gendler!

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by Ann » Thu Sep 25, 2014 5:11 am

That's a splendid picture! I love all that detail in the arms of Andromeda, and the NGC 206 region is the best.

And I love it when Rob Gendler works his magic on all that fantastic data gathered by large telescopes! :D

Ann

Re: APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep

by owlice » Thu Sep 25, 2014 4:55 am

Quite gorgeous!

APOD: NGC 206 and the Star Clouds of Andromeda (2014 Sep 25)

by APOD Robot » Thu Sep 25, 2014 4:06 am

Image NGC 206 and the Star Clouds of Andromeda

Explanation: The large stellar association cataloged as NGC 206 is nestled within the dusty arms of the neighboring Andromeda galaxy. Also known as M31, the spiral galaxy is a mere 2.5 million light-years away. NGC 206 is near top center in this gorgeous close-up of the southwestern extent of Andromeda's disk, a remarkable composite of data from space and ground-based observatories. The bright, blue stars of NGC 206 indicate its youth. In fact, its youngest massive stars are less than 10 million years old. Much larger than the open or galactic clusters of young stars in the disk of our Milky Way galaxy, NGC 206 spans about 4,000 light-years. That's comparable in size to the giant stellar nurseries NGC 604 in nearby spiral M33 and the Tarantula Nebula, in the Large Magellanic Cloud. Star forming sites within Andromeda are revealed by the telltale reddish emission from clouds of ionized hydrogen gas.

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