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# Marvin Jenkins

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753

1. ## Halton Arp picture problem

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.
2. ## Halton Arp picture problem

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?
3. ## Halton Arp picture problem

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
4. ## Halton Arp picture problem

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
5. ## Halton Arp picture problem

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
6. ## Halton Arp picture problem

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.
7. ## Halton Arp picture problem

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. ## Halton Arp picture problem

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
9. ## All the planets in one night

Solid cloud here anyway, thankfully or I might not have been able to resist. M
10. ## Halton Arp picture problem

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
11. ## All the planets in one night

Still not interested!
12. ## All the planets in one night

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

14. ## M31 with a DSLR and tripod

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
15. ## Stephan's Quintet passes the grunt test.

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
16. ## M31 with a DSLR and tripod

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
17. ## REFLECTION NEBULAE - EEVA STYLE

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

19. ## To set up or not to set up, that is the question.

It’s completely cloudy so I didn’t set up so I am not happy. M
20. ## A frustrating night. NGC 7662 and M76

If it’s in the centre then I am taking it as the central starIn all seriousness it looks to be about as bright as the least bright stars in the background. Is there a way you could identify any of the background stars to compare 16.6 mag? Marv
21. ## Aperture Fever. Is there a cure?

That's what the future obs is going to be for, not just observing but hiding all the future kit.
22. ## Aperture Fever. Is there a cure?

I used to know a guy who replaced his carbon road bike every year like some kind of drug fix. Very expensive and asked if his Mrs was ok with it. His reply.... As long as it is a red Specialized she never knows. Shame I can’t go from my 6 inch newt to 12 inch. Even keeping the colour the same I am sure she would notice. Marv
23. ## To nebula or not to nebula.

I completely understand, EP leading to Camera is normally what happens (did with me) but jm1973 needs to find the target first to photograph it. Also it was quite an in-depth post so it covered a fair amount. Marv
24. ## It's another M31

No such thing as another. If I get board of M31 time for the scopes to go. Really like the wide field/ mosaic. Really puts it in its place in the darkness. M
25. ## To nebula or not to nebula.

I know Astro can get confusing and very frustrating especially when trying to get a Goto mount working just how you want it. Firstly I have to say with all respect to replies to your original op, you seem to be trying to find the Ring Neb via an EP. This is doable with a 200p just takes some practice and a little knowledge of that bit of sky. You are doing nothing wrong. Just take your time and don’t complicate anything. If you cannot find an object in the EP then adding cameras is probably going to add questions. If you find it, then definitely add a camera. Try finding something like M13 a large bright glob in Hercules. See it in your finder scope first, compare it’s position to stars in the square of Hercules. A large target like that is the way to learn an object in relation to its surrounding star field. Planetary nebula are bright so seem a great choice, but they are so small they are very hard to to find. I have had nights when I know the Goto is perfect but I have had ten minutes at the EP to realise that the center object in the fov is not just another star, but the ‘target pn’ ! Happy hunting and clear skies. Marv
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