NGC 3199 is a Wolf-Rayet nebula: a most amazing, extraordinary beast in which light pressure alone from a huge star expels the outer atmosphere. This atmosphere will necessarily be mostly hydrogen, with some oxygen and a touch of yet more heavily processed stuff such as sulphur and nitrogen dredged up from the depths.
This particular beastie is moving toward the right relative to the pre-existing interstellar medium, and consequently there is something of a bow shock happening on the right hand side of the image. The [SII], though scanty, does seem to form discrete thready structures.
Last night we added another 5.5 hrs of [SII] taken with an FLI PL16803 to the 13 hrs of [SII], 7 hrs of H-alpha, and 9 hrs of [OIII] previously taken with an Aspen CG16M in 2016. Total exposure 29 hrs.
20 inch PlaneWave. Field approximately 37 min arc, North up. Astrodon 3nM filters.
As usual, apart from the cameras, all robotics and software including acquisition and processing software designed/built/written by us. Nothing from the fish market or from Doyles.
Processing:
- Wavelet noise filter
- Deconvolve
- Separate into stars and starless, map stars to white.
- Colour balance the nebulosity to be on average colour neutral.
- Wavelet sharpen the nebulosity (increase contrast by just 60%)
- Recombine.
In exciting news, our third Honda EU300iS generator died this morning, minutes after taking the last sub. That averages one every 4 years. That's it. No more generators. Our lithium batteries and solar are ominously still at least a couple weeks away, a bit like controlled nuclear fusion.
The bits of "fluorescence" add delight to the scene...
... rather like the bits of toffee in Hokey Pokey ice cream (something our En Zud readers will surely appreciate )
Like Hokey Pokey...I like it...in fact like it a lot
The bits of "fluorescence" add delight to the scene...
... rather like the bits of toffee in Hokey Pokey ice cream (something our En Zud readers will surely appreciate )
Like Hokey Pokey...I like it...in fact like it a lot
Love the detail in the ring area Mike. There is an interesting smoky look to those knots of dust and gas. I did this one many years ago now with the TSA. I really ought to take another look I think after seeing this version of yours.
Great image - well seen & the colour palette works!
Not too sure about the bright red stars... maybe no colour stars would be a better fit?
Love the write up about the science behind it too, well done!
Thanks Andy. Out of some 10,000 stars automatically converted from original narrowband colours to white, we missed about 150 conspicuous ones. This is now fixed.
Love the detail in the ring area Mike. There is an interesting smoky look to those knots of dust and gas. I did this one many years ago now with the TSA. I really ought to take another look I think after seeing this version of yours.
Quote:
Originally Posted by strongmanmike
Lovely
I really like the way those brighter knots and globules in the arc, really look like they are inside the blue gaseous envelope, very cool
Beautiful aquas, blues and greens too, very nice job guys
Mike
Quote:
Originally Posted by gregbradley
Another new object.
It looks dim. Well done on an interesting view of an unknown (at least to me) object.
Pretty cool Mike. That's one from the vault that you keep adding to. Getting deeper and deeper each iteration.
Thanks Marc. One of the best things about the hobby: one can keep adding to the Very Best Favourites. Adding more depth. Adding another panel to the right, to get that interesting bit just out of field. Doing another filter. Reshooting the brightest bits on a night of rare seeing. And of course reprocessing them in the light of experience and (gulp) constructive comments.
Thought I'd mark WR 18, the star that powers the nebula. I looked it up in the Simbad database, found the J2K coordinates, and then plate-solved our image.
It's pretty faint, not the one you might guess if you didn't know.
It's way, way off centre, because the star is travelling to the right relative to the interstellar background, and creating a bow shock.
)
