Marvin Jenkins

A thing of beauty. Well done. I have been there once before and it still leaves a chill.

Time to visit my doctor to see if my crossed fingers will ever work again.

I had an odd situation when I did mine. There was a long blond hair across the mirror. I made the mistake of pointing this out to my wife who has dark Afro hair.

I can honestly say that my grade 4 buzz cut is not the culprit, and I am sure that I have never seen a long haired blonde at my scope. I am sure that having a telescope means that I am immune from female attention. Not to mention my interesting repartee about the difference between magnitude and apparent magnitude.

Yeh, still got it going on.

Marv

Your final question about expected magnitude of a quasar at one billion lys distance. I have a distance in my notes for MK205 of 1100 mlys, that’s just over a billion right?
I will try to find out what magnitude this quasar is listed as. Why do I feel another question coming up?

If lensing is the cause of MK205 appearing to be next to NGC4319 then would the lensing effect cause 205 to appear differently, ie magnified in size or brightness?
 

Marvin

6 hours ago, Gfamily said:

Oooh, 

Q1 I guess you got from here, but I'm not sure where that 'function' came from, and of course, that's for quasars down to magnitude 23, whereas  MK205 is a thousands (or tens of thousands) of times brighter. 

Q2 The Sloan Digital Sky Survey has identified in the region of 5-600,000 quasars (according to the wiki), so the number may be a bit less

Q3 Hmm, maybe (are you including dwarf galaxies?)

Q4 What!!!?!!! NGC4319 is about 3' by 2.5' - which is about 1/480 of a [square] degree, so even if there were 2000 galaxies, that would only be about 4-5 square degrees in total

Q5 Do we see ~200 Quasars behind galaxies? 

 

Question - what is the 'expected' magnitude of a Quasar at about 1 Bly distance?  I'm trying to find its magnitude. 

You got to give me at least one mark for attempting it. I did say it would take me a while to get an incorrect answer.

Q1 source space math.gsfc.nasa.gov I did see the SDSS figure but you cannot beat a source with nasa in the title.

Q3 was a list of all galaxies including dwarf up to 100 million lys. The source was NED and I cut it down from 2500 to 2000 as our prime concern was galaxies out to a distance of 77 mlys.

Q4 is definitely my problem, or I didn’t understand your question. My understanding is there are 41253 square degrees of sky, so how much of that sky is covered by our galaxies in question?

I forgot to look at square degrees of sky as 60 minutes of arc x 60 minutes of arc (squared) I worked out a rough area in arc minutes squared of a galaxy, multiplied it by 2000 for the amount of galaxies to get total arc minutes squared of all the galaxies we are using. I agree with you that they would only cover 4-5 deg in total.
 

Q5, No we do not. I make 310 quasars per square degree of sky, so five degrees of sky covers 1550 quasars. So the closest 2000 galaxies obscure 1550 QSOs.

So back to ARP and his picture of NGC4319, if a single galaxy can produce gravitational lensing (?) and most galaxies are obscuring a background quasar then a lot of observable galaxies should be showing an optical illusion companion?

Do you know of any other galaxies within 100mlys that have the same situation or similar as NGC4319 and MK205? I can’t find any but I am not sure where to look.

Marv
 

On 26/09/2020 at 11:42, Gfamily said:

I may be wrong, but my thoughts would aim to keep it as simple as possible - so would be along the lines of... 

Q1 "How many quasars do we know there are?"

If we assume they are randomly distributed the next Q is

Q2 "How many are there per 'square degree' on the sky?"

Now; we know NGC 4319 is a close-by (relatively) galaxy - so its angular size is larger than most. 

So let's ask  -

Q3  "How many galaxies are as close (or closer ) as NGC4319?"

and Q4 "What's their combined angular size?"

Then you can ask -

Q5 "Given the total angular size from Q4; how many Quasars (as per Q2) would be covered by a part of a galaxy as close as NGC4319?"

 

 

I’m back with an answer. Fried my brain to tell the truth. One of the hardest parts is to find accurate data to start with.

Q1. 12.8 million

Q2. 310

Q3. About 2000

Q4. 1200 square degrees

Q5. 2000 galaxies covering 372,000 Quasars at an average of 186 quasars per galaxy.

How did I do?

Marv

Put me out of my misery please. Tell me it is gleaming and back where it should be not being used a dog water bowl.

M

It has been thirteen hours. I can’t keep my fingers crossed for much longer. How did the cleaning go?

5 hours ago, jetstream said:

All I know is that I could see more of this in my 24"

QSO J2240+0321

Wow. Please give a description. What does the object look like through that monster? 24 inch Dob! Stuff of dreams.

Marv

I am going to give that a go. See you next year😁 I will have a bash at it but it will take some time to come up with an incorrect answer.

14 minutes ago, andrew s said:

A bit like Olbers paradox.  I suspect it is a combination of QSO were only active for a finite period and the Universe is too young for all QSO light to have got here yet.

Regards  Andrew 

Now that is an interesting thought. So if we know the distance by redshift of NGC4319 and the distance by redshift of MK205 we know how far in the background MK205 is.

I am right in assuming that because MK205’s light has reached us from a far farther distance it is older than the galaxy?
If a QSO is active for a finite period, then would that period of activity be shorter or longer than the life of a galaxy by comparison?

The maths to calculate the number of quasars expected around a galaxy!!! I said I read the book Bang and looked on the web for an hour not completed a degree😂

Seriously though, how does one go about such a task?
 

As to my comment about expecting galaxies to have quasars if lensing is present, perhaps I should have said object. I was thinking along the lines of ‘If a single galaxy creates lensing, so any decent sized galaxy with an object behind it should show the distant object as an optical close neighbour’ Perhaps I am simplifying things too much.

Marv

10 hours ago, Gfamily said:

You'd need to look at the figures, but you may need to consider the effects of gravitational lensing, as that can have a magnifying and brightening effect.

I'm not saying it is that in this case, but it's a possibility.

I have had a look at that idea. It is clearly an extraordinary effect as predicted by Einstein and captured in that stunning image not so long ago. The only thing troubles me about gravitational lensing in this instance is that I have noted it being used in reference to large gravitational areas like galaxy clusters.

Just a presumption, but if one galaxy NGC4319 can create gravitational lensing then I would expect most galaxies to have a QSO as a neighbour. My basic idea is that if we are looking at a galaxy and it has another some distance behind it, it would be shown by lensing. With the amount of galaxies lensing should be evident a lot of the time I would have thought.

Marvin

I had to laugh though. Put in a search for NGC4319 in the NASA Hubble site and it came back with unknown.

I tried again in upper case and the site came back closed due to maintenance!

Just a coincidence I know, but what a time for that to happen.

M

3 hours ago, Marvin Jenkins said:

Are there any other examples of galaxy pictures from Hubble looking like that. I am a Hubble image fan (aren’t we all) and I cannot ever remember seeing this before.

I will have a good look through the archive on the web and see if I can more. Do you  know of a link specific to that type of Hubble image?
 

Marv

Found some. I didn’t know that the wide field took pictures like that. Seems I have been seeing pictures that slightly cropped for display purposes.

I saw the black area and thought redaction. Thanks for the info.

9 hours ago, Gfamily said:

The Wide field and Planetary Camera 2 on the Hubble Space Telescope always produced that shape of image, as there were separate imaging zones

 I think you can discount a conspiracy to hide 'the truth'  

https://en.wikipedia.org/wiki/Wide_Field_and_Planetary_Camera_2

Are there any other examples of galaxy pictures from Hubble looking like that. I am a Hubble image fan (aren’t we all) and I cannot ever remember seeing this before.

I will have a good look through the archive on the web and see if I can more. Do you  know of a link specific to that type of Hubble image?
 

Marv

8 hours ago, Gfamily said:

This might also set your mind at rest. 

http://www.kopernik.org/images/archive/n4319.htm

"Recent Hubble Space Telescope spectra show an absorption feature in the spectra of MK 205 that is in fact at the same red shift as NGC 4319. This would seem to show that MK 205 is indeed a much more distant object with some of its light being absorbed as it passes through NGC 4319"

I did wonder about that possibility and MK 205 being in some form of optical alignment but there seems to be a problem. Taking into account all of the above and using the revised red shift to attain a distance of MK 205 surely means that MK 205 is impossibly large and bright.
Any thoughts?

Marv

Solid cloud here anyway, thankfully or I might not have been able to resist.

M

With my ongoing efforts to expand my understanding of Cosmology from very little to a little bit more I managed to get my head around the current accepted idea of how our universe came into being, thanks to the excellent book Bang.

I have been aware for sometime about the ARP catalogue of peculiar galaxies and found out a little about Halton C Arp, it’s author.

I have noticed a few curious and discouraging remarks about his observations. Wikipedia states his observation of the galaxy NGC4319 with a companion QSO interacting with the galaxy and connected by a bridge even though the two objects have different red shifts has been disproved.
Furthermore, the conclusion that these objects are in very different parts of the universe has been proved by their different red shifts!!!! That’s the whole point of Arp pointing out the physical connection.

I googled the ESA Hubble image of NGC4319 and the attached picture is what I was confronted with on the ESA website. It seems obvious this a blatant bit of censorship.

I realise that insisting that red shift as a concept is fundamentally flawed has the effect of calling into question the expansion of the universe and the Big Bang which might annoy the establishment. 
However, blacking out a section of a picture that is real visual data is extremely troubling to me.

If this is the case then how do the Astro scientific community plan to deal with future sky survey data and Hubble pictures, lock it all away under lock and key in case it does not fit the current model? I thought science was based on observation/hypothesis/testing not ignoring and censorship.

Marvin

Still not interested!

Oh no, not again! After enthusiastically spending all night out after Stu gave us a heads up on the last one, only for the clouds to roll in so I couldn’t see Venus and Mercury, I vowed never again.

Marv

🤞

Great thing about DSLRs, you can push everything, a bit at a time and see the results right there. A lot to be said for following formula, but experimentation is the key. Don’t be afraid to push to the limits, you can just chuck crap subs in the bin.

On a mount of some description reasonably well polar aligned. Focal length around 50mm, ISO 800 ish, F3 to 4 you may well be able to go 20 second exposures.

Marv

2 hours ago, domstar said:

I had another look on Friday night. I got the same feeling at 100x. There's something there. It could be an unresolved star.

Just wanted to know your thoughts about The Splinter? You mention it in passing. I realise that the post is about the Quintet, but I was gob smacked with the splinter. So much so, I did a three hour imaging run on it not realising how faint and distant it really was.

I need to look through my observing diary, but I am sure I was trying for the Quintet when I ended up frustrated and discovered the Splinter. What is it about seeing something so distant for the first time?

Marv

Great first time effort. I know I had a couple of bites at the Andromeda cherry before I got a useable image.

I am not going to say anything to do with doing anything wrong, you have already proved you can get focus and frame your target which is the main battle.

I would suggest you try slightly longer exposure lengths. Try a test shot at ten seconds and see if you have star trailing. I may not be right of course but I would be tempted to lower the ISO a tad and try for ten or so longer exposures. No trailing, get a few more subs.

You have captured M101 perfectly out on the edge and have shown that you can get something out of stacking software and Gimp, took me months. Keep up the good work DSO imager.
 

Marv

Super interesting. I had no idea that this kind of object existed, at first glance I was wondering why you were posting a distant comet pic but talking about reflection nebula.

It has to be said that from your very detailed description it sure is one odd object. Thank you for the effort and the info, I will be following this thread with interest.

Marv

I have been smiling all the time following this thread. What an enthusiastic report of an amazing, infuriating, difficult target.

I am one of the newly initiated having my first view of the W Veil at the end of July. I had often wondered about this spectacular nebula having seen loads of amazing pics on this site.

I had not bothered to try before as most of the chat mentions it only appearing with Olll filters and such which I do not have yet, so I had it way down on my list. I have to say that I do not have much light pollution, at worst B4 and my nearest village 3k away turn off the lights at midnight.

I think light pollution may well be the biggest problem. I have a six inch newt and on a nice clear night I got my first look at the W Veil without any filter and after some adaptation, without averted vision. E Veil was also realised the same way. No fancy eyepieces either, Orion plossl’s.

Well done everyone involved, I know how much it means as I danced like a nutter round the garden when I realised what I had in the EP. For all of you still trying, I am sure that with equipment upgrades and/or dark site visits it will happen for you too.

Marvin