Hubble's Hidden Treasures Contest 2012

[geckzilla]

I know this picture has a few gigantic flares and seems a bit empty but when I scroll over it I feel it is strangely beautiful.

It's some part of NGC3077. "Phoenix" was mentioned as part of the target name but I'm not sure what that means.
R F658N (H alpha)
G F555W (green)
B F435W (blue)

[Ann]

Fascinating, geckzilla. I agree with you that it is beautiful. But I'm a little confused. NGC is the forgotten third member of the interacting trio, M81, M82 and NGC 3077. This is a Hubble image of the starforming center of NGC 3077.

It makes me wonder what part of the galaxy we can see in your image.

Ann

[geckzilla]

Oh, I can definitely help with that. You want to go to the footprints tab at the HLC. Here's my specific dataset: http://hla.stsci.edu/hlaview.html#FlFoo ... 2CGHRS&ds= (The orange one on the bottom left)


And here's another morsel. It's only H-alpha and infrared, this time. I suspect it's another one of those galaxies obscured by our Milky Way, but maybe not? Not sure how to figure that one out.
Nerdy bit: For some reason, the F814W still had the cosmic strikes in it. Most of the time, anything worth looking at has an automatically cleaned up version. No luck for me, this time. However, it did motivate me to devise a way to clean them up on my own quickly instead of feeling like an idiot combing through it manually.

R = F814W
G = .6R + .4B (half of red plus half of blue results in the some kind of inbred data for green)
B = F658W

NGC2985

[Ann]

Thanks, geckzilla! Nice. NGC 2985 is a so-called flocculent spiral galaxy, with myriads of small arm fragments rather than long elegant spiral arms. Its colors are somewhat red, particularly its U-B color, which suggests that it doesn't have much star formation. This explains the choice of filters here. The F814W infrared filter is a standard for Hubble images of galaxies and star clusters, but the Ha filter is somewhat unusual. Since the Ha filter tracks emission nebulae and therefore star formation, I'd say that one important purpose of the exposures here was to learn about the amount of star formation in NGC 2985.

Like I said, that's a very nice image!

Ann

[Beyond]

It reminds me of a circular blade. In this case, one with blue diamond tipped cutting edges.

[avdhoeven]

Hi Geckzilla,

You're really making great progress. I see improvements with every image. Nice to see that. I also have processed some more galaxies I would like to share... I think this is a great topic and hope that much more people will tag along during the competition!

NGC 5806

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The heart of M94

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NGC 201

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All full resolutions can be found via my flickr photostream

[Ann]

Very nice, avdhoeven! Your images look very good.

I'm particularly fond of your M94 image, and I'm glad that the colors are so good. M94 is truly fascinating. A small bright yellow nucleus is surrounded by a small bright yellow lens, threaded with spiraling dust. Outside this yellow lens is a "greenish" inner bulge. I've seen this greenish color before, and I think it is amazing. I don't for a moment think that our eyes would be able to see this part of M94 as green, but I do think that the greenish color suggests an intermediate population. I can't remember even having seen such a clear age difference between the nuclear lens and the inner bulge of a galaxy. Fantastic. How old are the greenish stars here, when did M94 start making them, and when and why did it stop?

And then M94 has a fantastic, rather large, brilliant ring of star formation outside the inner bulge. Apart from this sparkling ring, M94 has relatively little star formation. It does, however, have very large, faint outer arms which are blue from star formation. What an amazing galaxy!

Your image does the different colors and populations of M94 full justice. Thanks, avdhoeven! I really appreciate getting such a fine Hubble image of M94!

Ann

[geckzilla]

I don't suppose this is a very visually interesting image. I found that there were 5 different filters provided for this so it was mostly an experiment on figuring out how to combine them when I've only got 3 channels to work with. What I ended up doing is creating 5 layers, assigning the 5 separate channels their own masks, and then setting the layers to Linear Dodge (Add) which allowed me to control the individual contribution of each channel channel on the fly instead of trying to tinker with it in grayscale.

NGC4559 X7

[neufer]

I don't suppose this is a very visually interesting image. I found that there were 5 different filters provided for this so it was mostly an experiment on figuring out how to combine them when I've only got 3 channels to work with. What I ended up doing is creating 5 layers, assigning the 5 separate channels their own masks, and then setting the layers to Linear Dodge (Add) which allowed me to control the individual contribution of each channel channel on the fly instead of trying to tinker with it in grayscale.

• It might please a passing Papilio butterfly. (Geckzillas don't eat them do they?)

<<Papilio butterflies possess six types of photoreceptors and may have pentachromatic vision [The papilionid Papilio xuthus eye contains the largest number of butterfly photopigments so far described, with one UV (P360), one B (P460) and three LW (P515, P530 and P575) (Arikawa, 2003) (Fig. C).] The most complex color vision system in animal kingdom has been found in stomatopods (such as the mantis shrimp) with up to 12 different spectral receptor types thought to work as multiple dichromatic units.>>

[avdhoeven]

M8 Lagoon nebula

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This image was processed before by the Hubble team but in a totally different way. In their image the hubble palette was used, using 3 images. For this image 6 different bands were used:

hst_06227_02_wfpc2_f658n_wf_sci
N2: used as yellow
hst_06227_02_wfpc2_f673n_wf_sci
SII: used as red
hst_06227_02_wfpc2_f953n_wf_sci
SIII: used as magenta/red
hst_06227_02_wfpc2_f487n_wf_sci
h-beta: used as lightblue
hst_06227_02_wfpc2_f502n_wf_sci
OIII: used as blue
hst_06227_02_wfpc2_f656n_wf_sci
H-alpha: used as green

The luminance was made from the SII and H-alpha channels.

In this way much more detail in the center can be seen than in the original hubble processing.

Geckzilla:

I saw your previous mail about the different channels. What is interesting is to use the technique of putting the layer as screen and using an adjustment layer to influence the hue/saturation. It's described here.

[geckzilla]

Getting exotic there, Andre! Gives the nebula a kind of embossed look. I like it. I'll have to have a look at that video later.

And man, I need to pick some targets that are easier to make look pretty. This one just annoyed me.

ESO594, otherwise known as the Sagittarius Dwarf Irregular Galaxy
R 814
G 606
B 475

[geckzilla]

For this one, I realized that a lot of blue specks I thought were stars weren't stars, after all. I wonder how many blue specks I've left in other images that should have been cleaned up? Also, man, I wish more images were shot with three channels. There's a plethora of wonderful dual filter images out there but they leave the colors a little boring at times.

This is NGC4485. The glow to the lower right is a larger (closer?) galaxy that it's interacting with, NGC4490

[Ann]

Once again, fascinating, geckzilla and avdhoeven!

Copyright: Robert Lupton and the SDSS Consortium

NGC 4559, eh? That's one of the NGC designations I have memorized, because it refers to a relatively blue galaxy. This SDSS g-r-i galaxy shows the galaxy to be very non-yellow, and indeed its colors are really quite blue. This GALEX image shows that NGC 4559 is full of far ultraviolet light, mapped as blue.

NGC 4559 X7, eh? Could that mean an X-ray source in NGC 4559? Could you perhaps show us where in NGC 4559 this X-ray source is located? (I note that emission nebulae look green in your image. Does that mean that no Ha filter was used?)

Avdhoeven! Your picture of the Lagoon Nebula looks so much better than the way it did when the Hubble people processed it! Talk about their picture being full of weird colors!

Geckzilla, I like your Sagittarius Dwarf Irregular galaxy, too. The stars in it look very blue. Well, it is a starforming dwarf with little obscuring dust, so I guess that's why.

Click to view full size image

Copyright: Volker Wendel and Bernd Flach-Wilken

Geckzilla, here is your galaxy NGC 4485. It's the small one interacting with a larger one, as you said. Both these galaxies are forming a lot of new stars.


You said:

Also, man, I wish more images were shot with three channels. There's a plethora of wonderful dual filter images out there but they leave the colors a little boring at times.

I couldn't agree more!!!!!

Ann

[avdhoeven]

Ann: thanks for the nice comment. Now cross my fingers that maybe one of these images one day will be an apod...

[geckzilla]

NGC 4559 X7, eh? Could that mean an X-ray source in NGC 4559? Could you perhaps show us where in NGC 4559 this X-ray source is located? (I note that emission nebulae look green in your image. Does that mean that no Ha filter was used?)

Yes, it's an x-ray source. I wasn't ambitious enough to figure out where the x-rays were. I did try to find an image that I could add and overlay the x-ray source but I couldn't find one. Ha filter was used but the light was equally bright or brighter in 555 which I mapped to a slightly yellow green so it turned the nebula yellow. Totally forgot to list the filters that time. Oops.

[geckzilla]

These sorts of galaxies require tedious curve manipulation to make sure conspicuous bands of color don't appear in what should be a smooth gradient. It's no wonder we don't see many of these processed because they offer significantly less satisfaction for the amount of work they require.

NGC1380 (F475W, F814W)

[owlice]

Nice galaxy, though, geckzilla! I like this. I cropped the large image:

[attachment=0]geckzillasngc1380.jpg[/attachment]

Look how pretty that is! Great job!

[Ann]

You did a splendid job considering what you had to work with: two exposures, one through a blue filter and one through an infrared filter.

NGC 1380 is a typical "red and dead" galaxy. So-called "red" galaxies aren't red, of course, but they are indeed yellow, and this is indeed a very yellow galaxy. It is classified as an SB0 galaxy, a lenticular barred galaxy with no arms and virtually no star formation. Its colors are typical of such a galaxy: its B-V index is 0.940 and its U-B index is 0.450. This is exactly what we should expect from a red, that is yellow, galaxy. So why does a yellow galaxy look so blue in your picture of it?

Well, sigh. This, too, is exactly what we should expect from a picture of a yellow non-starforming galaxy taken through one blue and one infrared filter. These yellow galaxies are in fact quite non-infrared. Oh, they emit a lot of near infrared light, but 814 nm is far infrared. Far infrared light typically traces dust and star formation. Take a look at NGC 1380. Is there a lot of dust in that galaxy? Hardly. There is that tiny little dust ring around the nucleus, but no other dust is visible.

Starforming galaxies are typically blue, but they are even more infrared. Starforming galaxies are typically brighter in far infrared light than in blue light. Non-starforming, dust-poor galaxies are typically fainter in far infrared light than in blue light, even though they are not particularly bright in blue light, since they are intrinsically yellow.

Okay. NGC 1380 is a typically yellow, dust-poor, non-starforming galaxy. We should therefore expect it to be brighter in blue light than in far infrared light. And indeed it is. Its B magnitude is 10.921, but its far infrared magnitude is 12.866, almost two magnitudes fainter. So if you show the exposure taken through the blue filter as blue and the exposure through the infrared filter as red, and then create a sort of pseudo-green by mixing the two exposures, then you are going to end up with one bright blue, one faint green and one faint red picture of the same galaxy. Mix them and you'll get what looks like a galaxy that is overwhelmingly blue, even though its true color is completely non-blue.

Sigh. But you made a great job, geckzilla.

Ann

[geckzilla]

I actually did my best to make it look a very neutral color. I think it is quite neutral, though it does lean more toward blue than yellow, because it looks cleaner that way.

[Ann]

A true-color picture of NGC 1380 would make it look yellow-white. But with the exposures you had at your disposal, I'd say it was impossible to achieve that look. Not unless you wanted to map the blue exposure as a red picture and the far infrared exposure as a blue picture. That would indeed have made the galaxy look yellow. On the other hand, you would have ended up with a blue dust ring!

Ann

[geckzilla]

Here's a somewhat difficult one... Easy enough to process, but to explain it takes away from it a little. This is imaged in Ha and Nii so it's actually very red. In fact this thing is pretty much nothing but red. There's a few other pictures of it in Hubble's archive, but the only very clear ones are in Ha and Nii so I've put Ha in the red channel and Nii in the blue. There's a decent image in F502N but it was taken a little over a year later and the blobs have progressed significantly since then and it didn't feel right to use data from both years. If it were imaged again this year an animation showing how rapidly the nebula is moving could be created.

This is GK Persei and the surrounding gas and dust is aptly named the Firework Nebula.

[geckzilla]

Ok, this one was very strange. This came from the PHAT (The Panchromatic Hubble Andromeda Treasury) project. The image I started with was over 16000 pixels wide and was just a sea of noisey stars. Looking at it, you'd think you were looking at a section of our Milky Way because so many individual points of light are visible. Usually, stars in other galaxies are more of a fine mist or cloud-like structure with only supernovas ever standing out as their own entities. Not so with Hubble's close up of Andromeda. And with two filters, 417W and 814W, I was able to produce a color image. Because 814 is infrared, I ended up selectively darkening the reddest areas to create visual interest and contrast. Otherwise, it would just be a sea of bright orange and blue specks.

This is the general area imaged (not the exact shape) http://www.geckzilla.com/apod/m31_phat_ ... tprint.jpg

M31 "Brick 15"

[avdhoeven]

I just started with a 180 megapixel mosaic of M106 of the hubble data. Here is the first layer (555nm), which is still under progress. The image in the link is 50% of the original size (it's huge!).

M106 555nm

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Full image

[geckzilla]

Oi, I was eyeing that myself but was afraid of all those gaps and the difficulty of putting all the pieces together. Great job, so far.

Actually, I think some of the color data was missing for the core of the galaxy and that was what finally put me off. Maybe I'm thinking of another. So you have color data for all of that? Damn, nice find, if so.

[Ann]

Ah, GK Persei! Nova Persei! Nice, geckzilla!

I like your Andromeda picture, too. You have processed a picture of a really blue part of M31, so the blue color is fine. Of course, some parts of the image contains a bluer population than others, and you do a fine job bringing it out.

Best of luck processing the Hubble data for M106, avdhoeven! I very much hope that they have imaged it through filters that will make it possible for you to create a nice color picture!

Ann