LMC and SMC extended halo, streams and dust mark ii.
I took this set last weekend at my dark site.
Its 58 x 30 seconds ISO1600 tracked on a Vixen Polarie.
Lens was Sigma Art 35mm F1.4.
The processing has been push hard in order to see the extended halo, the tidal stream and the dust.
No flats though but I don't think it would change the outcome. Vignetting was corrected in Lightroom and lens corrections done there. This is similar to flats for a digital camera.
I am also imaging this currently with my FLI camera and hope to show something there as well soon.
You can clearly see a tidal stream coming off the top left of the SMC and there is an odd long bar to the right of the LMC that looks like a rake. Not sure if that is a tidal stream of stars or is it compressed dust? It looks like that strange hammer shaped tidal stream that comes off the bottom of NGC1097.
I captured the tidal stream of the SMC once before;
Also a stream of dust looking material seeming to flow towards the LMC to the bottom right.
Also around the SMC there seems to be a gap in the dust. Could that be a gravitational effect? Image processing may play a part here so later images would help confirm that is in fact a detail.
After having asked for images of the area in 2016, Dana, username Weltevreden SA on IIS, wrote about that "Magellanic Mystery" in February this year. Here as well as on cloudynights: https://www.cloudynights.com/topic/6...olved-at-last/
It's light reflecting 'galactic cirrus' - in this case Milky Way cirrus, not actually from the MCs. Can be seen with naked eye from very dark sites, as well.
Comes out really well in your over-processed image. I bet she'd be happy if you drop her a PM with a link to your image in reference to her article.
I'm absolutely fascinated by that phenomenon since I read about it. All Sky projects have mapped it, too. It's very faint, very beautiful, and it's "all around us".
After having asked for images of the area in 2016, Dana, username Weltevreden SA on IIS, wrote about that "Magellanic Mystery" in February this year. Here as well as on cloudynights: https://www.cloudynights.com/topic/6...olved-at-last/
It's light reflecting 'galactic cirrus' - in this case Milky Way cirrus, not actually from the MCs. Can be seen with naked eye from very dark sites, as well.
Comes out really well in your over-processed image. I bet she'd be happy if you drop her a PM with a link to your image in reference to her article.
I'm absolutely fascinated by that phenomenon since I read about it. All Sky projects have mapped it, too. It's very faint, very beautiful, and it's "all around us".
Cheers Annette
Thanks very much for that link to her report. Very informative indeed. So it is part of this Magellan ghost. I thought it looked like dust. What confuses it is the small star tidal stream from the SMC.
I'll send her a link to the image. I think I'll wait though as I am planning more extensive imaging over Christmas from my dark site.
I am currently imaging it with a Nikon 50mm F1.8 lens and a FLI Microline 16200 but that is from semi rural skies and I am not sure if its going to work.
Looking pretty good so far Greg! I’ve wanted to try and do the dust in this region more myself but don’t have a lens to cover it at the moment. Planning on rectifying that in the new year
You’ve shown the dusty regions quite well so far even without a lot of exposure yet.
from semi rural skies and I am not sure if its going to work.
even IF it isn't - that would be valuable information for the community, too. Your fast 50mm lens captures the whole area of the 2 MCs plus surroundings which is very neat in this regard.
I hope I'll notice when you post your result sometime after Christmas.
And I hope someone can can shed light on the origins of SMC's extended "arm". Not sure whether Dana had mentioned it in her reports. I'll try and skim through it again..
The "stuff" is all around us - it only needs a good light source so it reflects that light and we can capture it.
A German guy did an image of the "stuff" around a very bright variable star. He chose a variable star from this database http://cdsportal.u-strasbg.fr/?target=HIP%2017884to seek the faint beauty around it bc apparently variables are en vogue in the professional astro-community and his image, if it showed something beautiful, would gather more momentum.
He imaged with a 11" SC, produced 35 hours, made of 50 secs frames. Finn's Nebula (named after his nephew): https://www.astrobin.com/378375/
Bigger regions photographed with 2 cameras side by side and from a darker site than possible in Germany could shorten the amount of precious cloudless imaging time, significantly....
Looking pretty good so far Greg! I’ve wanted to try and do the dust in this region more myself but don’t have a lens to cover it at the moment. Planning on rectifying that in the new year
You’ve shown the dusty regions quite well so far even without a lot of exposure yet.
Thanks. It took some massive stretching though. It would be good to have several hours of data.
Quote:
Originally Posted by silv
even IF it isn't - that would be valuable information for the community, too. Your fast 50mm lens captures the whole area of the 2 MCs plus surroundings which is very neat in this regard.
I hope I'll notice when you post your result sometime after Christmas.
And I hope someone can can shed light on the origins of SMC's extended "arm". Not sure whether Dana had mentioned it in her reports. I'll try and skim through it again..
Quote:
Originally Posted by silv
The "stuff" is all around us - it only needs a good light source so it reflects that light and we can capture it.
A German guy did an image of the "stuff" around a very bright variable star. He chose a variable star from this database http://cdsportal.u-strasbg.fr/?target=HIP%2017884to seek the faint beauty around it bc apparently variables are en vogue in the professional astro-community and his image, if it showed something beautiful, would gather more momentum.
He imaged with a 11" SC, produced 35 hours, made of 50 secs frames. Finn's Nebula (named after his nephew): https://www.astrobin.com/378375/
Bigger regions photographed with 2 cameras side by side and from a darker site than possible in Germany could shorten the amount of precious cloudless imaging time, significantly....
My dark site is very dark, almost no light pollution. I saw that variable star image - very impressive.
Quote:
Originally Posted by multiweb
Looks like you've got all the right bits in there now.
Cheers Marc. The F1.4 helps a lot.
I think its the sort of image where I could simply set up the Polarie tracker and mirrorless and an intervalometer and get it to pump out a bunch of images. I'll take several flats, darks and bias frames.
It shows some of the same structures that I've seen before in images from Andrew Lockwood and a couple of others. Very nice!
I have been hoping to do this with a fast lens and CMOS camera but we keep having new moon weekends that coincide with crap weather.
Cheers,
Rick.
I took a few hours with a Nikon 50mm F1.8G on my FLI ML16 last week but the initial processing (not very extensive) was not showing any of this.
It may be that it requires a very dark site and no moon. Next time I have that opportunity I think I will go for a long exposure and see what I can get.
It's fascinating what you got out by really pushing that image, Greg, much more than we expect. The extended SMC arm that Annette mentioned is actually debris from the more recent (500 Myr ago) sideswipe interaction between the LMC and SMC. This stream is a gas bridge, out of which the long stream of new HII and star clusters between the two galaxies originated. The LMC didn't come out of it terribly well, either: it lost an entire arm & is today a one-arm galaxy – which is why the upper quadrant of the LMC is such a fulminous place while the bottom half is so barren. The ancient and younger populations in the LMC's bar were jarred loose from each other; the younger population (~6 Gyr old) now lofts about 3,000 light years above the ancient population and tilts upward toward the Tarantula Nebula region at an 8° angle. There was an earlier encounter 2.3 Gyr ago in which the SMC was tidally stripped of a large number of then-middle age stars, which now for a second "red giants" bridge beneath the young gaseous bridge visible in your image.
The angular spike rising to the r. of the LMC is indeed a dust filament in our own galaxy, extending out into the halo about 300 lyr below the MW disc. It is a very enigmatic structure. I've taken to calling it the "Chameleon Spike" because it emanates from the same Galactic cirrus structure that gives us "Magellan's Ghost" (as Annette astutely pointed out). I enlarged your image and noticed that the 3 faint clumps descending from the LMC toward Apus are the three ultra-faint dust features called "Magellan's Ghost". They seemed a bit reddish to my eye. Your image is the first I've seen to clearly show the underlying dust structure shared by the two features.
The Chameleon Spike is truly enigmatic. See this Google Drive image – it's an image of the magnetic fields in the same area your image covers, though rotated quite a bit clockwise. The patch of brownish blobs in the centre is the LMC. The magnetic flow lines reveal the Spike to be a completely inexplicable eruption out of the low-intensity Galactic ambient field that rotates with the arms. When there are magnetic field lines of this density there is a lot of electron flow, and those electrons carry dust with them – that's the dust in the ascending filament that your image captures. The Spike is a really mystifying feature that shows up in every electromagnetic band from gamma all the way down to sub-mm but is quiet in the optical and radio. All the hydrogen and dust bands vividly trace it, so it is a thermally hot feature. Why it should suddenly erupt out of the Galaxy from such a quiet locale is a mystery. I haven't found any papers in the professional papers that study it.
So back to your shot, Greg, you really packed a lot into your 58 30-sec shots at 35mm f/1.4. Kudos!
It's fascinating what you got out by really pushing that image, Greg, much more than we expect. The extended SMC arm that Annette mentioned is actually debris from the more recent (500 Myr ago) sideswipe interaction between the LMC and SMC. This stream is a gas bridge, out of which the long stream of new HII and star clusters between the two galaxies originated. The LMC didn't come out of it terribly well, either: it lost an entire arm & is today a one-arm galaxy – which is why the upper quadrant of the LMC is such a fulminous place while the bottom half is so barren. The ancient and younger populations in the LMC's bar were jarred loose from each other; the younger population (~6 Gyr old) now lofts about 3,000 light years above the ancient population and tilts upward toward the Tarantula Nebula region at an 8° angle. There was an earlier encounter 2.3 Gyr ago in which the SMC was tidally stripped of a large number of then-middle age stars, which now for a second "red giants" bridge beneath the young gaseous bridge visible in your image.
The angular spike rising to the r. of the LMC is indeed a dust filament in our own galaxy, extending out into the halo about 300 lyr below the MW disc. It is a very enigmatic structure. I've taken to calling it the "Chameleon Spike" because it emanates from the same Galactic cirrus structure that gives us "Magellan's Ghost" (as Annette astutely pointed out). I enlarged your image and noticed that the 3 faint clumps descending from the LMC toward Apus are the three ultra-faint dust features called "Magellan's Ghost". They seemed a bit reddish to my eye. Your image is the first I've seen to clearly show the underlying dust structure shared by the two features.
The Chameleon Spike is truly enigmatic. See this Google Drive image – it's an image of the magnetic fields in the same area your image covers, though rotated quite a bit clockwise. The patch of brownish blobs in the centre is the LMC. The magnetic flow lines reveal the Spike to be a completely inexplicable eruption out of the low-intensity Galactic ambient field that rotates with the arms. When there are magnetic field lines of this density there is a lot of electron flow, and those electrons carry dust with them – that's the dust in the ascending filament that your image captures. The Spike is a really mystifying feature that shows up in every electromagnetic band from gamma all the way down to sub-mm but is quiet in the optical and radio. All the hydrogen and dust bands vividly trace it, so it is a thermally hot feature. Why it should suddenly erupt out of the Galaxy from such a quiet locale is a mystery. I haven't found any papers in the professional papers that study it.
So back to your shot, Greg, you really packed a lot into your 58 30-sec shots at 35mm f/1.4. Kudos!
=Dana in S Africa
Wow, I didn't realise so much was known about the history of the LMC and SMC.
Hopefully I get some clear skies after Christmas and I can do a much longer set of exposures on this.
Your fast 50mm lens captures the whole area of the 2 MCs plus surroundings which is very neat in this regard. 
