Ultra Deep M83 The Thousand Ruby Galaxy

[strongmanmike]

Firstly, to fully appreciate the depth achieved in this image, make sure you turn up the brightness on your phone, or ideally view on a computer monitor in a dimly lit room and adjust/increase your screen brightness appropriately, this grey scale (https://pbase.com/strongmanmike2002/image/55347254/original) can help. Please enjoy a surf around any of the Full Resolution versions linked to below.

Ultra Deep image of M83

This is an extremely deep image of the southern spiral galaxy M83 and immediate surrounds, in Hydra and is perhaps (?) even the deepest, as far as revealing extended diffuse features, that has ever been compiled of this galaxy, while also displaying the full dynamic range of the scene and in colour? The image shows a wealth of detail** across the galaxy disc and main spiral arms and both Halpha and OIII data have been included in the image to better reveal the extensive star forming regions across the galaxy. Generally considered an intermediate sized spiral, an extensive outer halo, that envelopes the galaxy out to over 24 arc min in diameter, has been revealed, this is approximately double the normally referenced apparent size of 12.5 X 10 arc min, for the galaxy. At the distance of M83, this apparent size equates to an actual diameter of over 110,000 light years. Not previously seen this clearly, subtle contrast enhancement applied to this halo has revealed it to be comprised of a number of very faint but distinctly separate, long spiral arms, that wrap around and envelope the galaxy. Also seen and first revealed by Malin and Hadley (1997) in deep amplified photographic plates, taken with the UK Schmidt Telescope at the Australian Optical Observatory, is a very faint outer stellar stream (bottom left), whose curve is closely concentric with and located somewhat distant from and north west of the galaxy.

**NB: No Blur Exterminator or other AI based sharpening was used on this data.

The data for this image was collected over six nights during April, May and June and on all but one of those nights, when the seeing bloated out for a couple of hours (not even good enough for RGB!), the seeing was most excellent, with the raw FWHM of the Lum frames, as measured in MaximDL, consistently ranging between 1.5" and 1.8" over the more than 27 hours of data collection, which is very helpful in preserving detail and acheive my goal of revealing some actual stellar resolution in the galaxy arms. I am convinced I need a finer image scale than 0.84"/pix, in order to take better advantage of such conditions...fingers crossed I can get some smaller pixels in the light path some day, for the good nights :thumbsup: :prey:.

See the image on:

Astrobin (https://www.astrobin.com/jgfcv2/)

Pbase galleries (https://pbase.com/strongmanmike2002/image/174678436/original)

Flickr (https://www.flickr.com/photos/strongman/53822910716/in/dateposted/)

This high contrast stretch (https://pbase.com/strongmanmike2002/image/174647434/original), reveals the full extent of the galaxy halo and confirms that the outer halo is likely also physically connected to the distant north west stellar stream.

Here (https://pbase.com/strongmanmike2002/image/174681230/original) is a link to an annotated version identifying the many peculiar star clusters and stellar nurseries found straying way out in the galaxy halo

Here (https://pbase.com/strongmanmike2002/image/174681208/original) is a composite of some of the many distant galaxies around M83

This paper (https://iopscience.iop.org/article/10.1088/0004-637X/789/2/126/pdf) by Barnes et al. provides some interesting insights into the structure and formation of M83 and the nature of the north west stellar stream.

Hope you enjoy :thumbsup:

Mike

[croweater]

That is beautiful Mike. With that stream at bottom left shown so clearly could now be called "the rat tail galaxy". Well worth all those hours"work".
Cheers, Richard

[joshman]

Wow! Mike, that is stunning. Even more so to get that kind of resolution without the use of "AI" based sharpening routines.

[RobF]

Have you tried more dithering and drizzle perhaps Mike before going to a smaller pixel camera?

Amazing and inspiring work - thanks for sharing. Have just been "galaxy surfing" some of the other galaxies visible which are amazing in their own right too - the 2 larger ones in your thumbnail are really showing some nice detail. :eyepop:

[alpal]

Hi Mike,
that is a fantastic image.
27 hours and 30 minutes of integration.
L,Ha,OIII,R,G,B = 15hrs, 4.2hrs, 3.2hrs, 1.6hrs 1.6hrs, 1.75hrs.
You have really excelled this time.
As expected so many other distant galaxies have popped out.

cheers
Allan

[keller60]

Not bad at all...but I don't think its the deepest M83 out there.


Rolf Olsen's near 70 hour epic exposure does look deeper.


Cool rendition just the same.

[strongmanmike]

Thanks so much Richard, yeah it does look a bit like a rat or possum tail in this orienation huh? cool :thumbsup:



Thanks Josh ma'man, who is soon to have a mount nearly as good as mine :P :lol: :thumbsup: Gotta love AP mounts, when does it arrive? :prey: Yeah I see soooo few images that have used BlurEx where it isn't as obvious as DB's, that I just can't warm to it as a "look" :shrug: the odd imager out there has managed to use it without being obvious but still get some benefit and those are ok I guess? :confuse3: :thumbsup:



Yes the Drizzle thing has been suggested before Rob and I keep meaning to have shot at it...buuut seems I am a creature of habit :shrug: :doh:...besides, a finer physical image scale is better than drizzling, like better seeing always trumps RL decon, BlurEx or other sharpening :)



Thanks Al, yeah always a lover of seeing a myriad of background galaxies :love: but it was the massive extended halo with spiral structure that made me swoon this time :love2:

Thanks all for the nice comments :hi:

Mike

[strongmanmike]

Ah huh..On ya Peter ;)

[Startrek]

Mike,
Wow !!
Excellent M83 with resolution and detail us mere mortals can only dream about.
Well done from the top of Australia
Also love the wide outer spirals beyond the main structure ( rarely exposed )
Glad to see you finally bit the bullet and joined Astrobin , a great hosting platform with loads of features ( my second year on it )

Cheers
Martone

[keller60]

Odd reply :shrug:



Just sayin' it's good, but not as deep as Rolf's.


Adam Block also has a CDK24 10 hour effort with more faint fuzzies but does not show the halo quite as much.



Cheers
Bill

[strongmanmike]

Cheers Martone :thumbsup: I certainly could not find a single other image of M83, regardless of telescope size, that shows the full extent of the outer halo and with structural detail along with a clear north west arc and in full dynamic range colour :shrug: but no problemo, happy to be shown one if there is one, be great to see, really :thumbsup: :)

Yeah I bit the bullet and joined Astrobin, it has some nice features :thumbsup:

Mike

[gregbradley]

Stunning Mike and a great choice of target.

Was there much signal in the O111?

Greg.

[strongmanmike]

Hi Greg, thanks a lot mate, imaging motivation has been lack luster this year, grief is a funny thing, very dynamic and changes perspectives a bit but I'm still enjoying getting up there, just in a less manic, must take advantage of every bit of clear sky time, sort of way, more chilled :)

Yes, there was plenty of OIII but I'm not sure it particularly added much to the image as I'd hoped? Some of the slightly teal tones in the central 50% of the main galaxy have been caused by this OIII.. I think? :question:

Mike

[Retrograde]

Wow Mike - this is amazing.

I love the outer halos and tidal tail and all the detail in the faint fuzzies that just appear as amorphous blobs in most images. :thumbsup:

[strongmanmike]

Thanks Pete, glad you like it, not quite a "discovery" but it's always nice to be to see a very well imaged object in a new light :thumbsup:

Mike

[AdamJL]

Good grief, that's a killer image. Amazing work, Mike. Just perfect.

[alpal]

Hi Mike,
you're right and I see a definite place for long exposure images
taken with fast Newts. - extreme deep fields.
Nothing else seems to pick up those faint halos so well.
Is it Rolf Olsen who pioneered that?
NGC5128 with NASA data added showed us the way:
https://www.rolfolsenastrophotography.com/Astrophotography/Centaurus-A-Extreme-Deep-Field/i-XH3VRsC/A

cheers
Allan

[strongmanmike]

Rolf is a legend and yes I think his 120hr Cen A, completed back in mid 2013, illustrated the effectiveness of uber long exposures and may well have started the trend...now, some ten years on, there are whole groups of imagers combining efforts to compile amazing 200hr, 300hr+ exposures :eyepop:, that are revealing vanishingly faint features and have made numerous discoveries, it's almost a kind of magic :) Eventually there will be more of these collaborations and much, or all, of the sky will likely have been imaged in this manner..?

At 27.5hrs, my M83 is a mere token effort in comparison...but still, I'm happy with the outcome, my location helps :thumbsup:

Mike

[Paul Haese]

Nice capture of the outer arms of M83. I like the colour too. I remember reading about the outer arms a few years back now and wondering at the time if my GSO RC12 could capture it from my obs at Clayton Bay.

I do wonder what my 16" RCOS could capture at the altitude you are working from though.

[strongmanmike]

Thanks Paul

I'm currently at an image scale of 0.84"/pix, I'm confident the seeing quality I consistently see, would suit 0.42"/pix on many nights. My current telescope actually suffers from some astigmatism, not a huge amount but enough to mean my MaximDL measurements indicating the majority of my subs are sitting at 1.4"- 1.8" across the year, are actually more like 1.2"- 1.6" were my scope aberration free. It's actually annoying me, so yes, very confident a scope like your 16" or a smaller pixel camera on my scope, would definitely excel at high resolution imaging at Eagleview, the extra sampling could handle some more decon as well.

Mike

[alpal]

Hi Mike,
yes - with Paul's RCOS 16" at FL = 3,414 mm and
ZWO2600MM Pro pixel size of 3.76 microns
his arc-sec per pixel ratio is: 0.23 arc seconds.
https://www.wilmslowastro.com/software/formulae.htm#ARCSEC_PIXEL


With your telescope -
Just using the ideas of the Nyquist sampling theorem if you
ever got sub 1 arc second seeing you would need a minimum of
0.5 arc seconds per pixel to properly measure it.
So any measurement below 2 x 0.84"/pixel or 1.68 arc seconds seeing
is probably not accurate?

Paul's telescope could take full advantage of the seeing at your wonderful location.
Can anyone please correct me if I'm wrong?

cheers
Allan

[strongmanmike]

On the subject of sampling and seeing....one funny comparison is with my last effort on the same galaxy (https://pbase.com/image/159520083/original) back in 2015, from my last observing site at Wallaroo close to Canberra, with all the same imaging gear and processing software...bloody no comparison :eyepop: looks like crap, I knew it wasn't my best work at the time and it's much less exposure, I remember it was a one night quicky... I now realise just how crap it was :lol:

Mike

[alpal]

Hi Mike,
You did well.
Look at what I got:
the FWHM values I were getting were 4.9 arc seconds measured with Maxim DL.
https://www.flickr.com/photos/24719437@N03/8715470059/in/datetaken-public/

cheers
Allan

[rmuhlack]

Impressive Mike. Good to see another example of M83's extended halo and loop. With my 8inch newtonian and similar integration I was able to reveal the loop with a heavy stretch, though not with the level of detail and clarity you have in your image (which comes from mountain top seeing/transparency, more aperture, faster optics, mono sensor etc as well as your deft processing). Nicely done.

Have you seen the earlier 1997 Malin and Hadley paper (also cited by Barnes et al 2014) which also mentions M83's extended halo and loop?

[strongmanmike]

Aaah well, we all manage to create muck occasionally :P :lol:



Thanks glad you liked it Richard :thumbsup: yes saw that paper and it will be linked to from a famous site tomorrow :D ;)

Mike

[alpal]

yes Mike - when the seeing is as bad as 4.9 arc seconds it's not worth proceeding -
all you get is a blurry mess but -

when you've gone to all the trouble of setting
the system up it's hard to resist taking some kind of image.
Some nights I measured as bad as 6 arc seconds FWHM.
I think the best night I ever got in Melbourne was 2.9 arc seconds
FWHM and that was only between 2 am any 5 am using an Ha filter.
Your results getting between 1.5" and 1.8" over the more than 27 hours of data collection
are very impressive and from a dark site as well.

cheers
Allan

[Andy01]

Congratulations on today's APOD, Mike; well done, a fab deep image with real scientific value! :party2:
https://apod.nasa.gov/apod/ap240703.html

[alpal]

Wow - Mike is a mega star now - well done.
It's a beautiful picture.

Allan

[strongmanmike]

Thanks Guys, was a nice surprise this morning, I haven't submitted to APOD for some time but I really liked the result here and thought meah, I'll give it a shot :thumbsup:

Mike

[gregbradley]

Congrats Mike.
Well deserved. It’s the best image I have seen for ages
And there have been plenty of superb images on this site.

Greg

[seeker372011]

Congratulations on an APOD

[AdamJL]

Well-deserved indeed, well done, Mike!

[Kuz]

Congratulations on the APOD Mike well deserved :party2::party2:

[strongmanmike]

Wow, thankyou so much fellas, your kind comments mean a lot :thumbsup:

Mike

[DiscoDuck]

Congrats Mike. Wonderful image and very well-deserved recognition.

[strongmanmike]

Cheers Paul :thumbsup:

Mike

[Stephane]

Wow, how did I miss this? This image is incredible Mike - especially given you haven’t used any AI sharpening tools. Congratulations too on the well-deserved APOD!

[strongmanmike]

Cheers Stephane, he he yeah I think it may even annoy some people when I mention the lack of AI use :P, sorry :ashamed:, it's just that AI "decon" gives most images a different look, it's usually obvious and just doesn't look quite real to me :shrug: and people are starting to see that as kinda "normal" but I don't recon it is, so I just like to make it clear that I don't use it. Not a life changing issue just a personal muse and go ahead and use it, no one goes to jail :lol: ...buuuut if you have to, please use it sparingly :thumbsup: or..?.. don't :question: :lol:

Mike

[TrevorW]

Beauty mate :)

[strongmanmike]

Cheers Trev :thumbsup:

Mike

[markas]

Mike, congrats on the APOD.
The galaxy's outer reaches show up amazingly - as almost never seen, and the clarity of detail in the main spiral is spectacular.


On the matter of resolution, I'm sure you are right. I recently changed from 1"/px to 0.65"/px, and it shows at my Mt Macedon site which never gets much better than 1.7" seeing...


I'm very jealous of you getting so many hours of sky time - recently I've been lucky if I can two decent nights with good seeing in one dark period:sad:


Mark

[strongmanmike]

Cheers Mark, always wanted to do a good deep M83, I originally wanted more exposure but after three months of slow collection, I was impatient to see what I had and started processing and woah! I was gob smacked...so, meah, just kept going and all the aspects I was hoping for were revealed, without all the extra exposure that I had imagined would be necessary, the blessing of transparent dark skies I guess? :thumbsup:

Since starting digital imaging back in 2003, I have done serious imaging (and visual observing), from various spots around Canberra, Maitland, Newcastle, Kurri Kurri and from Wiruna (ASNSW premier dark sky site) and Eagleview edges out or completely floors all of these places, in all aspects, seeing, darkness and transparency, its great :thumbsup: So I am not surprised your drop from 1"/pix to 0.65"/pix is returning dividends for you from Macedon. All my gear was extensively utilized for nearly 8 years, at my old observatory at Wallaroo, on the outskirts of Canberra and then simply moved 60km south and 850m higher into the Tinderry's and the improvement has been mind boggling, in every session, both visual and imaging :thumbsup: So yes, I am sure dropping my image scale finer will be worth it.

You can see my conditions quantified and some comparisons between Wallaroo and Eagleview HERE (https://pbase.com/strongmanmike2002/site_comparison), it's no fishing story, I'm not making it up :)

Mike

[alpal]

Amazing comparisons Mike,
you'd hate to be trying to image from suburban Melbourne
where the seeing is often 6 arc seconds FWHM.
I've seen Jupiter and Mars from a park in Melbourne
with high end refactors.
The seeing pops in and out -
you see those planets clearly for less than a second at a time.
It would be good only for video and lucky seeing -
selecting the best frames and stacking.

I bet lucky seeing from Eagleview would be well below 1 arc second.

cheers
Allan

[Nikolas]

All I can say is well done!!!

[strongmanmike]

Yes considered giving that a go, Kevin Parker does just that and has recently done some great work on some small planetary nebs, if you're on it, here is his Facebook page (https://www.facebook.com/groups/943624572325939/user/100003210439708/) :thumbsup:



Cheers Nik, and sure, that'll do :)

Mike

[alpal]

Thanks Mike,
I'm not on Facebook so your link didn't work.
I can see this link -
https://www.facebook.com/kevin.parker.735507/

is that correct?

Allan.

[strongmanmike]

Yep, that goes straight to Kevins FB page :)

Mike

[Ant0nio]

Congratulations Mike,
A cracking M83 up there with the best of them & a well deserved APOD. :thumbsup:

Cheers,
Tony

[strongmanmike]

Grazie Mille Antonio :thumbsup:

Just noticed it managed to score a Top Pick on Astrobin today too, very cool :D only just joined Astrobin a week or so ago and it was my inaugural image posted there, so glad at least a few enjoyed seeing it :)

Mike

[GFBrown]

An excellent photo of a very well named galaxy

[CoolhandJo]

wow thats a fantastic image Mike. So deep and so much detail!!!

[strongmanmike]

Thanks very much guys :thumbsup:

Mike

[DJT]

Lovely image Mike and, as always, useful detailed information behind it. Learning loads. Keep at it.

And also congrats for the APOD

David

[strongmanmike]

Cheers mate, good to hear and will do :thumbsup:

Mike

[E_ri_k]

That’s stunning mate, I love everything about this image. One of my favourite galaxies.

Erik

[strongmanmike]

Thanks Erik :thumbsup: and yeah through my 18" Dob (https://pbase.com/strongmanmike2002/image/173309205) up at Eagleview it looks amazing visually too :thumbsup:

Mike

[astronobob]

Yeah amazing capers Mike, doing these deeds are in a sense the backbone to the hobby and an inspiration for future armatures to set personal goals etc.
Valuable stuff and a beautiful image for sure

[Dave882]

Crikey Mike that’s a spectacular images for my astro-starved eyes! Don’t think I have ever see m83 in such depth and clarity. Wonderful… just wonderful

[strongmanmike]

Cheers a lot Bob hope you are right :cheers:



Cheers heaps Dave and welcome back :hi:. Apart from the APOD (https://apod.nasa.gov/apod/ap240703.html) :D... it only gets better! (http://www.robgendlerastropics.com/M83-StarstreamBlend.html) :thumbsup:

Mike