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View Full Version : Object of the Week June 9, 2013 - Markarian 205 and the red shift controversy



reiner
June 9th, 2013, 02:37 PM
Mrk 205 and NGC 4319
Draco

Ra
12 21 44
Dec
+75 18 38

Mag 15.2 vis (Mrk 205)

Type: well, that is the question ... ;-)

This OOTW is going deep into the history books of cosmology. It is about a nice (at least on DSS) spiral galaxy, NGC 4319, and a quasi-stellar spot, Mrk 205, next to it. It is probably very special to astronomy, that tiny little specks such as Mrk 205 may cause large turmoil ...

Back to the year 1971. Edwin Hubble's theory of the expanding universe, reflected in a red shift correlating with distance appeared to be generally accepted. Well, not by everybody. Halton Arp took a deep photograph of NGC 4319 and Mrk 205 with the 200" Hale telescope, in which he suspected a "bridge" between the nearby spiral and the quasar, despite they had extremely different red shifts. His case was that they are close in space to each other and not a chance alignment along our line of sight. Arp was considering the hypothesis that the considerable red shift of the then new quasi-stellar objects or short quasars was not due to their distance from us. Instead, he suggested that they are objects being expelled from the nuclei of their "host galaxies" and that the red shift of their light had other reasons (such as, for instance, gravity). This was, of course, in strong disagreement to the general view of the scientific community, in particular Allan Sandage, leading to lasting controversies between the supporters of the two groups (with Arp's being certainly a minority).

If you are interested in this story and others, read the very interesting article about Arp's peculiar universe in Jeff Kanipe's and Dennis Webb's book about "The Arp Atlas of Peculiar Galaxies".

Here is an image of the galaxy group around NGC 4319 with on the DSS
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And here a close up NGC 4319 with the quasar
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The funny thing is: There is really something between NGC4319 and Mrk 205. Not distinct, but it is there. This HST Heritage image shows that the immediate environment of NGC 4319 is filled with matter, being outer parts of the spiral arms or perhaps as well some tidals due to interaction with other galaxies.

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What can we see visually? Well, Mrk 205 is a quasar and there's not much to see except for a tiny stellar thing. During my first observation many years ago with my then 14" Dob, Mrk 205 was not easy and could be seen only with averted vision somewhat offset from NGC 4319 (more offset as suggested by the DSS image). With my 22" it is visible all the time, even with direct vision, if I recall it correctly. No, I did not see a bridge.

Last week, I revisited this group (almost at zenith during early evening) and also looked at the other galaxies. Neighboring NGC 4319 (no pun intended :-) ) is a small galaxy with a faint halo and not much structure at first sight. After some time, I suspected the northern spiral arm as an extremely faint arc offset from the main galaxy. Conditions were not overwhelming, so this should be easier under proper conditions. Unstructured NGC 4291 is situated WNW of 4319 and situated as one of the cornerstones of a quasi-rectangular asterism. There is another galaxy, NGC 4386, offset to the NE of the two other NGC galaxies.


"Give it a go and let us know what you think about red shifts, bridges, and all that stuff!"

Good luck and great viewing!

Ivan Maly
June 9th, 2013, 07:14 PM
Nice choice. Hubble himself, as far as I heard, did not want to have anything to do with any overarching theories, and to the consternation of expansion enthusiasts who considered themselves his followers, till his dying days was saying "apparent velocity", in regard to redshifts.

Jimi Lowrey
June 10th, 2013, 03:41 PM
One thing that is on my to do list is to try for is the companion of Mrk 205.

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I had forgotten about it till you did this OOTW. " I will give it a go and let you know"

Uwe Glahn
June 10th, 2013, 06:21 PM
Cool pair Reiner.

I visited years ago, I have to try it once more, perhaps with the companion, thanks Jimi.

16", 129x, NELM 6m2
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reiner
June 10th, 2013, 07:44 PM
One thing that is on my to do list is to try for is the companion of Mrk 205.

Hi Jimi,

I still remember well that night, when I observed Mrk205 for the first time with my 14". It was my second quasar then besides 3C 273. And I was veeeery proud of being able to see this tiny little thing. And now you come up with observing its companion ... unbelievable ;-)

RolandosCY
June 11th, 2013, 12:26 PM
I did observe Markarian 205 on both June 9th and 10th. I had to, as it was an object proposed by Reiner who directed me to this great forum. Well, I must admit that Markarian 205 was relatively easy in my 18" on both evenings, and especially last night which was better and darker. The ideal view was at a rather high 488X obtained with a 7mm Nagler and 2X Barlows. I could keep it in view with direct vision at both 294X and 488X but it was easier with the higher magnification. NGC 4319 appeared as a soft glow with a slightly brighter core. No sight of a bridge or a ... companion (I will probably need another 30 inches for that!). Markarian 205 is the first quasar I have logged, thanks to Reiner for a great target!

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Howard B
June 11th, 2013, 08:11 PM
My latest observation of Markarian 205 is from the 2008 Oregon Star Party, so it's about time for another look this summer. My memory of this now rather old observation is that patience was rewarded, as was observing the same object in several scopes with a small group of fellow observers. Here's my eyepiece sketch:

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My notes say:

"This was fun! Lot's of nifty galaxies here, and one of the "stars" near 4319 is Markarian 205. 4291 and 4386 are both brighter than 4319 but together they make a sweet trio...257x to 467x. PS - Markarian 205 was pointed out by Candace (Pratt) as the faint star to the immediate right of 4319 in my sketch. Chuck (Dethloff) then noted a faint glow just above the quasar - cool!"

Jimi Lowrey
June 17th, 2013, 10:33 PM
A few nights ago I had a successful observation of the companion of Mrk 205. The seeing was rock steady and I was able to use super high power to see this small galaxy. The best view was with a 6mm ZAO with a 2X barlow @1464 X I also used A 4MM with barlow @ 2440 X.

Most of the time Mrk 205 had a tear drop look to it and in moments of good seeing the core of the companion would pop into view. I saw it as a separate galaxy about 8 or 9 times. The companion of Mrk 205 looked small and stellar when it would pop in to view. I was surprised that I was able to see it on my first attempt.

This is my raw sketch of the field that I did to verify my observation
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