A (formerly) lazy Sombrero Now with 13.75 hours

[Paul Haese]

With the weather starting heading towards winter one never really knows how many nights will be available for imaging. Over a couple of nights in the last week I have picked up some integration time on the Sombrero Galaxy (M104). It has been on my imaging list for many, many years. I took a single sub of it three years ago but never got the chance to go further with the image. With any luck I can pick up another 5-7 hours next week to beat down the noise in the back ground (the stuff I can see on my monitor). Not to mention the effect that high cloud had on my blue channel.

Click here (http://paulhaese.net/M104.html) for larger resolution image.

Edit: the link now shows the updated image with 13.75 hours. The attached image on the right has the new data added.

Halo now quite visible

[Peter Ward]

Very tidy indeed Paul. :thumbsup:

[gregbradley]

Yes that is excellent. The weather pattern is expected to go into El Nino mid June. That means drier, warmer winter. Hopefully that translates into more clearer nights.

Greg.

[marc4darkskies]

Very nice Paul - detail looks good and stars are pretty round. :thumbsup: Are you still cropping or is this the full frame?

Don't just apply more data to noise suppression though. This galaxy has a large halo worth teasing out.

Cheers, Marcus

[Paul Haese]

Thanks Peter for your comment.




Hmmm, I am less inclined to think the Bureau can predict weather even 3 days ahead of time; much less several months. Trends might appear to indicate El Nino but we are heading into a wet winter already. So far this month we have had nearly 60mm and the average for April is around 58mm. So who knows. I suspect El Nino has a greater impact your side of the continent than in the centre where we are. The Indian Ocean dipole is more relevant to us I think. In any event I am taking what I can at present.



Thanks Marcus. Since sorting out my PEC, the guiding has produced round stars consistently. I am doing some star reduction as most do these days and this can affect the roundness of the stars if the guiding slips for a bit with high cloud etc.

This is a crop but at 100% resolution. The full res image is huge and is in portrait due to guide star location, as you would know.

I had not considered the outer halo and that is just another reason to press onwards. I will have to read up on it. Thanks for the tip.

[Andy01]

Very nice rendition of a beautiful object - looking forward to the finished image :)

[Amaranthus]

Hubble shows what halo can be revealed: http://imgsrc.hubblesite.org/hu/db/images/hs-2003-28-a-print.jpg

[RickS]

A very good result, Paul!

[Placidus]

Superbly sharp. Optics, seeing, guiding all coming together. The dust detail is magnificent.

[tilbrook@rbe.ne]

Tack sharp Paul!:thumbsup:

Images like this must be very satisfying with all the time and effort invested in your setup.

Cheers,

Justin.

[bugeater]

Absolutely love it. Love the target and your image of it is amazing.

[Slawomir]

Superb image, well done!

Would love one day to be able to photograph galaxies, in the meantime, I will have to stick to narrowband...



Up North winter = imaging time! :-)

[Bassnut]

Very tight and sharp, well done Paul.

[alpal]

That's fantastic Paul,
you've got detail in the dust lanes.
I am amazed that a GSO mirror can give you those results.
Maybe you got a fluke mirror?

cheers
Allan

[kkara4]

fantastic again paul!:eyepop:

[alpal]

Hi Paul,

off topic:

I notice a picture of your is used in this YouTube video:

https://www.youtube.com/watch?v=IAZkpyFEbLg

Watch at 3 minutes 22 seconds.

cheers
Allan

[Paul Haese]

Thanks Andy, Rick, Fred and Krishan for your comments. Much appreciated.



Thanks for that Barry. Yes the halo is well evident in that image. Such an awesome image.




Yes slowly, slowly Mike. Its starting to be satisfying.




Yes Justin, it has been a long haul of persistence. Eliminating one issue after another has been a labour of perseverance. This hobby is certainly not for the impatient (to quote Anthony Wesley).



That is nice of you to say that. There are some very fine images of this image out there to inspire me too.



Thanks Slawomir. Yes having lived in Brisbane for 4 years once winter was the best time for photography of the night sky. Funnily enough it is the place where I started astrophotography, such a long time ago.



I seriously doubt it Allan. I have looked through several of these scopes now and each once properly collimated gives quality views. Jim Sheng is a very good reflector optician. They invested heavily in quality CNC machines and are very committed to providing a quality product. I have spent a fair bit of time with Michael Chaytor and Jim to develop these scopes to where they are now. In all that time the optics have been very good. My 8" was the second RC8 in Australia was very sharp and worked well once I sorted the baffle issues. So don't be amazed, the optics are very good.



That takes me back a few years ago. That image is still in my gallery. Down the list a way now. There are a few videos I did for Sixty Symbols a few years back now. One in particular on imaging Saturn. It was great fun and part of my interest in public outreach. They asked me for permission to use various images from my website and I was pleased to help them out.

[alpal]

Hi Paul,
I can say that there were people who seriously doubted that you could get
pictures of that quality with a system costing 1/5th of the price of
the usual premium optics producers but you have proven them all wrong.
Well done.
( I am trying to put a 10" f4 carbon fiber Newt. together to get great results
so I think along the same lines as you.)

What an honour to get on to a 60 symbols video -
you're on a roll.

cheers
Allan

[Nico13]

First class Paul, I really enjoy looking at your work.

[Peter Ward]

So..let's think about this a bit more critically....and not to take away anything from Paul's fine image...Paramounts/STXL's etc. are cheap now?

As I've been howled/down before for saying so, the best optics on the planet will look very ordinary on a bowl of jelly.

[theodog]

:mad2:

Isn't this discussion better suited to the "Equipment" section.

This thread is about the image.

Well done Paul, very tidy.:thumbsup:

[astronobob]

I must say, That is a Supurb result there Paul ...

[Paul Haese]

Thanks Ken and Bob for your comments.




I am sure there were plenty of people saying that. I know of two guys here that were quite open about thinking this. Who can blame them really? GSO, the new player on the block with a reputation of people needing to tinker a bit to get the scopes producing images. Not to mention going through development from a tube to a truss. Those of us who helped with feed back and ideas knew the optics were good, it was just the housing that needed to be stable. It's been a long haul, but things are looking good now.

Yes the 60 symbols videos were fun to do. I did those in 2011 I think after being Runner up in the Solar System imaging section of the ROG competition. It was pretty cool to be able to share my passion.





I am with you 100% here Peter. STXL issues aside and some issues with the Paramount MX; essentially you need to have a stable system to produce good results. Without a good mount/support you cannot get anything good out of the best optics/cameras.

Whenever I get asked about where to start I always say but a good mount and make it stable with a good pier and pier support. From there anything is possible.




Don't worry Jeff, I reckon it is pertinent to how I got the image. Thanks all the same. :)

[Paul Haese]

I have now added another 8 hours of data to the image. The halo should now be well seen and lots of tiny little galaxies have now popped out.

[alpal]

Hi Paul,
Nicely done - worth that long haul.

cheers
Allan

[Stevec35]

Yep - nicely done Paul. One of the best sombreros I've seen in recent years.

Steve

[SkyViking]

That's a very nice and smooth Sombrero indeed Paul. Apart from the fine detail I particularly like the colours :thumbsup:
One I should get around to too, I've only ever done a couple of hours on it and then managed to pick out over 130 globulars, so can only imagine what must be lurking in your image already!

[Geoff45]

Nice capture Paul, lots of good detail in the disk.
Geoff

[gregbradley]

That's a very fine Sombrero Paul. Very well processed as well.


Greg.

[Nico13]

That is great Paul, I was just looking at the full image and seeing all the little Galaxys surrounding it in deep field in particular to the left and just to the lower right, there are hundreds of them.
A very very nice image.
Thanks for showing it.

[Andy01]

That new data has really made a heap of difference-and that in itself os very educational- its a really beautiful image now. Are you intending on going deeper still? Well done again :)

[madbadgalaxyman]

Paul,

Most impressive how far that faint diffuse light seems to stretch outwards from the bright outline of this galaxy.

One of the puzzles in astronomy is why the halo of M104 should be relatively bright. In general, halos of spiral galaxies are very difficult to detect; at around 28-30 V magnitudes per square arcsecond.

In my view, the answer to this question is that M104 is actually an S0 galaxy rather than a spiral galaxy; the dust lane would be hardly noticeable if this galaxy were viewed face on!

Cheers,
Robert

I hasten to add, in an edit, that a lot of the " galaxy halo" detections reported in the IIS astro-imaging pages are probably not actually picking up the halo of a spiral galaxy.....mostly, the images are picking up a faint outer component of the planar disk structure, rather than the outer spheroidal halo component.

Here are some really good lecture notes on galaxy halos:
http://www.eso.org/sci/meetings/2015/StellarHalos2015/talks_presentation/ferguson_garching2015_online.pdf

The halo work by professional astronomers is really taking off exponentially, in the last few years; this is one of many specialized areas within astronomy that have benefitted from an unprecedented number of PhD students, postdocs, and early career researchers in astronomy;
each sub-field within extragalactic astronomy is now developing so fast that the poor Mad Galaxy Man finds it harder and harder to keep up!

[Paul Haese]

Thanks Allan, Geoff and Greg for your comments.



Thanks Steve, that is high praise, but much appreciated.



Thanks Rolf for your compliments. Hmm, I might need to investigate and do an overlay. Any suggestions for which programme to use. The SkyX does not seem to do that.




Thanks Ken. Yes there are lots of small galaxies in the field. Though not as many as in the current field of another project that I am undertaking.




No plans at this stage to go deeper. Though with an observatory I can always add more next year if I wanted.



Thanks Robert for your comments. Quite interesting. I will go and take a look at that thread. It might help with my processing of halos in future.

Talking to several high profile imagers at the AAIC a couple of years ago, it was interesting to hear the thoughts about imaging halos and tidal streams.

[Ross G]

A great looking Sombrero Galaxy photo Paul.

Nice colours and I love the fine detail.

Ross.

[ericwbenson]

Hi Paul,

This peaked my interest since I've thought of doing something like that with Aladin (http://aladin.u-strasbg.fr/) before. Playing a bit now...attached is what I came up with using a generic Simbad data query (the Simbad button near the menu bar) and 2 custom filters for globs. The image data itself is a stack of 9x20min luminance I took in 2013 with the CDK20 at ARO.

The custom filter definitions (which are new 'planes' in the Aladin software) are:
${V}<23 && $[src.class]="GlCl" {draw{V}}
and
${V}<23 && $[src.class]="GlCl" {draw red rhomboid}

BTW really well done on that image.

Best,
EB

[Peter.M]

I understand your reasons for cropping this, and its a great image as you have displayed it. But I really really liked the full frame composition that you sent to me.

[Paul Haese]

Thanks Ross for your comment.



Wow there appears to be a lot of globulars that I have captured. Not out of the ordinary I am sure but I had no idea that there were so many. It being a smaller galaxy than our own from what I have read; I expected not many would be present. Thanks for putting that up.



I totally understand; the full frame has so many back ground galaxies to see, but the portrait style and stars on the edge of the field bothers me. Pity there were not enough guide stars for landscape.

[Peter.M]

See, I really enjoyed the portrait orientation. Oh well personal preference.

[cometcatcher]

Wonderful image Paul! All the little galaxies around it pop out easily. The main image looks like one of the early Hubble images I remember seeing. Fantastic stuff.

[Amaranthus]

Updated version is fantastic Paul. Worth the extra data.

[ericwbenson]

Oh maybe a slight misunderstanding here. The data I used was from my scope since I had the FITS file with WCS fields (what Aladin wants). We would have to feed in your FITS file into Aladin to get the markers on your image. (I suppose I could try plate solving the JPG from your website).

EB

[ericwbenson]

Hi Paul,
OK here is your image plate solved in Maxim (after fooling it with a fake FITS header) and loaded into Aladin with the glob magnitudes. I put the cutoff for globs at Vmag 20.5, best I could do with the JPG.
BTW why is your image reversed left-right, artistic license?
(Normally a two mirror scope, or refractor, flips the image upside down)

Best,
EB

[Paul Haese]

Ah, that's ok Eric, I thought you had used my image.



Thanks Eric. There is still a lot of globs there. Thanks for going to that trouble.

I don't know why it came out that way. I was imaging at 283 degrees and it was originally on its side. Not flipped either in processing. Just rotated 90 CW and cropped to suit.

[Amaranthus]

It's basically the same orientation as that Hubble image. Just a little more skewed. And I know you took it Paul, because the diffraction spikes on yours are a little further rotated compared to Hubble's!

[madbadgalaxyman]

Hello Paul,

Halo studies are really hotting up, at present, in the professional community. They have pushed integrated-light imaging of halos to about 30 magn. per sq. arsecond, and they are currently trying for 32 magn. per square arcsecond.
See for instance work done with this interesting array of small refractors:

http://dunlap.utoronto.ca/instrumentation/dragonfly/

http://arxiv.org/abs/1401.5473

I am pretty sure that the professionals have figured out some pretty good tricks and techniques for reducing the effects of sub-optimal flatfielding, scattered light in the optics, and other factors that could make it difficult to detect extremely low surface brightness light.
I am not, however, familiar with the literature on this!

cheers,
Robert

And now, just for fun and profit.....

Very Deep Image of the Virgo Cluster to 28.5 V magnitude per square arcsecond, by Mihos and Harding of CWRU::
181257

[madbadgalaxyman]

See my comments in this thread as to the apparent magnitudes and angular sizes of the globulars associated with M104 ::

http://www.iceinspace.com.au/forum/showthread.php?t=76702&highlight=M104+globulars+number

Rhode and Zepf, in a 2004 paper, estimated a total population of 1900 globulars belonging to M104, but I am unsure how well this estimate has held up since then. They also estimated that the system of globular clusters stretches to about 19 arcminutes from the centre of M104.

cheers,
Bad Galaxy Man

I shall shortly "weigh up" the Milky Way Galaxy vs. M104, in terms of the relative luminosities of these two galaxies.
Hint: in any fight between the MW and the Sombrero, the Sombrero wins by a large margin.

[madbadgalaxyman]

G'day there, Paul,

Your question about the relative sizes and luminosities of the Milky Way and the Sombrero Galaxy has had me working on this problem for a couple of hours every day, for the last week.

The Sombrero has a rich (1900 +/- 200) globular cluster population for two reasons:
(1) It is more luminous than our own galaxy
(2) It has a gigantic spheroidal bulge/halo component(s)
vs. our galaxy which has only a very small central bulge. And there are more globulars per unit of galaxy luminosity in those galaxies dominated by a bulge or spheroid.

The luminosity data on the Sombrero has been relatively easy to find, but in an odd sort of way, assessing the total luminosity of the MW has been an unpopular problem in the professional literature (only about 4 attempts to do this, in the last 20 years).
So I am going to ask a couple of Milky Way specialists if they have some recent data on the luminosity of our own Galaxy.

There is an old figure of about absolute blue magnitude -20 for the luminosity of our own galaxy which has been endlessly rehashed in the textbooks, but this figure does not really cut it any more......it is disappointing for the amateur to realize that the textbook writers do not usually utilize the most up-to-date data!

cheers,
Robert Lang

P.S.
Relative diameter of the two galaxies is going to be easier to assess. Our own galaxy is certainly no more than 80,000 light years across.

The diam. of the sombrero can be assessed from the catalog angular diam. plus there is a good recent estimate of its distance. However, M104 is very very different from our own galaxy, as our own galaxy has only a very very very faint halo! Indeed, there are strong arguments for M104 being earlier than type Sa in the orthodox Hubble Sequence of :
E - S0 - Sa - Sb - Sc - Sd - Sdm - Sm - Irr

[Paul Haese]

Wow, thanks Robert for all the reading and interest you have taken in the topic. You're comments always make for interesting reading and I am sure I can speak for all; are always appreciated too. :thumbsup:

[madbadgalaxyman]

Thanks, Paul, I am glad people appreciate the information I provide.

But I will leave the imaging and most of the image processing to experts like yourself and others in this forum....your imaging discussions increasingly have the specialized sound of a discussion between professional astronomers!

Hargis and Rhode, in a 2014 paper, claim that the bulge (or the extended spheroid..... including the bulge and also the halo) is actually much brighter (in terms of its total amount of light) than the flat disky component , leading to an overall falloff of light with increasing radius, in M104, which is more typical of an elliptical galaxy!

They regard the spheroidal component of The Sombrero as being totally dominant over the planar disk component, though I personally have some doubts about this interpretation. There are several assessments in the literature that state that the integrated light of M104 is dominated by the light from the bulge/spheroid, so the numbers cannot lie.

Certainly, our own Galaxy is very much different from M104, as it has a prominent disk and a small bulge.

I will probably do a bit of a quick MW vs. M104 comparison in the Science Forum, though this project is snowballing and there is a great deal to know about M104.

Best regards,
Robert

[Leonardo70]

Stunning Paul ... just wonderful.

All the best,
Leo

[Paul Haese]

Thanks Leo.

[gvanhau]

Very impresive image Paul.

I think one of the best Sombreros I've seen.

Geert

[Paul Haese]

Thanks Geert. Several people have suggested that, but I know there are a lot of good ones out there. However, for a scope that cost very little (not counting the other equipment which makes a huge difference too), I am quite pleased with the result.