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NGC 7129 in OSC with IR950 Mouseover Overlay (For mouse-over of new revision) (Rev... (With NIR data inserted for the mouseover), Alan Brunelle
NGC 7129 in OSC with IR950 Mouseover Overlay (For mouse-over of new revision) (Rev... (With NIR data inserted for the mouseover), Alan Brunelle

NGC 7129 in OSC with IR950 Mouseover Overlay (For mouse-over of new revision) (Rev... (With NIR data inserted for the mouseover)

Getting plate-solving status, please wait...
NGC 7129 in OSC with IR950 Mouseover Overlay (For mouse-over of new revision) (Rev... (With NIR data inserted for the mouseover), Alan Brunelle
NGC 7129 in OSC with IR950 Mouseover Overlay (For mouse-over of new revision) (Rev... (With NIR data inserted for the mouseover), Alan Brunelle

NGC 7129 in OSC with IR950 Mouseover Overlay (For mouse-over of new revision) (Rev... (With NIR data inserted for the mouseover)

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Description

12-14-2022:
Revision posted here.  In fact I had to delete the original (with mouseover version) in order to be able to retain a mouseover capability with the new revision.

Corrected were lots of bad stars, star defects, noise, etc.  I had tried this twice before and really never liked it.  The new methods are much better.  But even though this is primarily a reflection nebula, it still does not thrill me.  Here I enhance the molecular clouds that are scattered about, and further deemphasize the stars, this time without artifacts.

Original Post Description:
This object is rapidly becoming one of my least favorite objects as an artistic endeavor.  Perhaps it is just not as visually exciting as I was expecting.  I do believe that this one would benefit from a larger aperture, long focal length scope, for the reflection nebula part.  I tried this a couple years back when I started astrophotography.  I was not happy then and never posted it.  This time, it was my hope to highlight more the surrounding molecular clouds and faint Ha emission nebulae instead of the "embryo" itself. 

What brought me back to this object was the fact that it displays a pretty high concentration of Harbig-Haro objects and other youthful stellar objects (YSO), including interesting IR emissions.  I did turn my 5 inch Mak-Newt with the QHY5III462 camera on the main subject here, using my 950nm edge filter.  For fun, I present that as a mouseover to the main OSC image.  Except for a simple stretch, the IR image is pretty much what I got.  Not so many interesting things to see with this, I did it more for fun and to learn to be more creative with mouseovers.  More exciting data hopefully awaits when I receive the 12 inch imaging Newtonian from Europe. 

What is interesting (or not as it may be) is that HH objects, though typically seen in red hues in the visible, generally do not show up in the IR bands from 1-4 uM.  That means the reds seen are pretty restricted to the visible.  These young stars are very buried in their nascent clouds and much longer wavelengths (and more expensive cameras!) are required to reveal them.  I think one of the half dozen or so remains faintly visible.

What is neat, though not surprising, is that the camera cuts right through the blue reflection nebula.  But why are those bright blue stars in this nursery not depressed in their signals (IR) relative to other stars?  (Normally, I see a strong reduction with this camera and filter with bona fide blue giants, which emit much stronger in the blue and UV and little in the IR.) The reason is all of these are classified as YSOs.  As I explained before, YSO are typically pre-main sequence stars in their early development.  That means that their H-fusion nuclear engines have not fired up yet.  Convection within these stars digs all the way to their cores, stirring up million degree matter, which by the time it surfaces is still very hot, blue hot.  But this means that cooler matter moves into the core and while still very hot, it has not yet gotten hot enough to ignite main sequence hydrogen fusion.  Once this is achieved, the structure of the star stratifies, thereby isolating the core from the surface.  While the core will achieve multiple tens of millions of degrees, the surface now settles into a temperature that more reflects the mass of the star.  And of course that temperature changes over the star's lifetime, which reflects other stellar "life" dynamics.  So why do these blue YSOs still remain bright in my IR camera?  (Where normally blue stars get dimmer and red star get brighter, sometimes dominantly bright.)  My understanding is that these young stars are still closely enveloped by their progenitor dense circumstellar disks, rocks and planetesimals, that themselves get heated by the star and emit light that I see in the region of ~1 uM.  But we generally do not see that in our visible devices because of the over abundance of blue light.  But the blue reflected light from the more-distant reflection nebula dust, which is otherwise cold at those distances from the stars, is easily dispensed with by my filter.

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