Author Topic: Sunday 15th July 2012: the Voorwerpje of NGC 5972  (Read 3937 times)

Alice

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Sunday 15th July 2012: the Voorwerpje of NGC 5972
« on: July 14, 2012, 10:45:30 pm »
Today's Object of the Day is this nice little galaxy:


587739845390761994, also known as NGC 5972.

You can also find this galaxy without the line of missing pixels on the Deep Sky Objects Browser.

Or with some extra lines on Sky Map. :D

Not all that much is out there about this galaxy - Deepskypedia has started a page on it, and it looks very empty, like the start of this Object of the Day when JeanTate first replied to it (see the first post! :D). This paper from 1995, by Verón and Verón-Cetty, argues that while the galaxy has previously been classed as an S0 galaxy (a lenticular - i.e. a disk without spiral arms), they disagree with this and believe it is an elliptical, a result of an old merger. They remark in the paper that no lenticular galaxy has yet had a feature this one contains, namely an "extended double lobe radio source" - that those are associated only with ellipticals - and this paper backs up that rule. (Will we find an exception; or has one already been found! :D) They add that the spectrum matches that of a Seyfert galaxy - in other words, with an AGN.

In future, though, I suspect Googling "NGC 5792" will bring more results! The nicest of them is of course Drew's Voorwerpje catalogue. And Bill has posted a couple of pictures . . .


In twilight at Kitt Peak


Kitt Peak again, this time a combination of filters

Tantalisingly, he remarked that "we already know about more than Sloan sees for this one". We also "know of emission-line structures that will spill right outside the field of view of the narrow-band filters". Indeed, it is the Voorwerpje with the most extensive areas of ionised gas in the whole project :o :o

A few days ago, the Hubble image arrived . . .

(click to enlarge)

That image is about 75,000 light years across - about three quarters the probable size of the Milky Way. The green is OIII like we get a lot of in the peas; the red is H-alpha, ordinary ionized hydrogen like we get in the Sun. As they say in the blog, there's a clear double helix - not something that the SDSS image, or the 1995 paper, seems to show!

Here's its spectrum, by the way - from Drew's website, not from this latest image.


We seem so far to agree with the 1995 paper about a double lobe radio source - as to its morphology, I'd say merger and not yet either a lenticular or an elliptical :D c_cld asks if it's a polar ring. So far there's not that much information on the blog, but I expect a great deal in time!

So what do we do whilst waiting for said information? We get Galaxyzooitis and start seeing other things in it, of course! Budgieye says it looks like a wrapped sweet. And, well, this weirdo looked at the middle and saw this . . .


« Last Edit: July 15, 2012, 12:11:30 am by Alice »

JeanTate

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Re: Sunday 15th July 2012: the Voorwerpje of NGC 5972
« Reply #1 on: July 14, 2012, 11:09:05 pm »
I'm sure it will be good - very, very good - when it appears  ;) :D 8) :-*

Alice

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Re: Sunday 15th July 2012: the Voorwerpje of NGC 5972
« Reply #2 on: July 14, 2012, 11:10:49 pm »
Hahahaha! I shall now move it with the reply! ;D ;D ;D

AlexandredOr

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Re: Sunday 15th July 2012: the Voorwerpje of NGC 5972
« Reply #3 on: July 15, 2012, 07:42:59 am »
 :D :D :D :D :D

Baby star opening its eyes on the Universe.

PeterD

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Re: Sunday 15th July 2012: the Voorwerpje of NGC 5972
« Reply #4 on: July 15, 2012, 08:02:59 am »
Fascinating OoTD! Lot's to digest.

Great vulture (?) and the blob-thing at the end :) Sometimes observational cosmology is more like a Rorschach Test...Horse's Heads, Antennae, Sombrero, BigFoot etc now this! :) :) :) :)

elizabeth

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Re: Sunday 15th July 2012: the Voorwerpje of NGC 5972
« Reply #5 on: July 15, 2012, 08:19:59 am »
 ;D ;D Awesome picture and wonderful work everyone a great present I would say for all zooities for our 5th year!

stellar190

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Re: Sunday 15th July 2012: the Voorwerpje of NGC 5972
« Reply #6 on: July 16, 2012, 12:28:29 am »
This is really awesome! I want to hug a voorwerpjes but my arms aren't long enough :'( And I now cannot un-see what you can see in the latest Hubble image :D :D

NGC3314

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Re: Sunday 15th July 2012: the Voorwerpje of NGC 5972
« Reply #7 on: July 16, 2012, 12:39:04 am »
(Grins hugely)

Mukund Vedapudi

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Re: Sunday 15th July 2012: the Voorwerpje of NGC 5972
« Reply #8 on: July 16, 2012, 04:21:25 am »
Lovely  :) :)
Faith is the bird singing when the dawn is yet dark.

StephanieC

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Re: Sunday 15th July 2012: the Voorwerpje of NGC 5972
« Reply #9 on: July 17, 2012, 12:18:47 am »
Very nice!

Budgieye

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Re: Sunday 15th July 2012: the Voorwerpje of NGC 5972
« Reply #10 on: July 17, 2012, 05:20:41 am »
Very complex.

Lightbulb500

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Re: Sunday 15th July 2012: the Voorwerpje of NGC 5972
« Reply #11 on: July 19, 2012, 06:37:10 pm »
Simply stunning! 8)

zutopian

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Re: Sunday 15th July 2012: the Voorwerpje of NGC 5972
« Reply #12 on: June 19, 2014, 03:47:39 pm »
Warning: this topic has not been posted in for at least 120 days.

Copy from another topic:

May be you could already confirm the tentative conclusion of this 1995 paper:
Quote
The analysis of the images of NGC 5972 shows that it is an E galaxy rather than an SO-a; this galaxy however shows some structures which are not identifiable with spiral arms but could perhaps be the result of a merger event.


Would NGC 5972 be a polar ring candidate?
 ::)  ::)

I think we entirely support the idea that NGC 5972 has undergone a merger - we see tidal streams, and the dust and gas are in multiple planes and twisted. It might end up as a polar ring, if we are really patient.

Warning: this topic has not been posted in for at least 120 days.

NGC 5972 has shown up in Radio Zoo Talk.:
http://radiotalk.galaxyzoo.org/#/subjects/ARG0002jh9
Talk discussion:NGC 5972: Galaxy with known voorwerpje and known doublelobe
http://radiotalk.galaxyzoo.org/#/boards/BRG0000002/discussions/DRG00006oe

I did following post in Radio Zoo Talk.:


http://skyserver.sdss3.org/public/en/tools/explore/summary.aspx?id=1237665566615666691

It is NGC 5972, which has a known voorwerpje (ionized gas cloud). Ref.: GZ paper by Keel et al.. 
One of the other NED Refs is as follows.:.

Title:  The Hubble type of the double lobe radio galaxy NGC 5972
Quote
We found in the literature a single example of a spiral galaxy associated with a classical extended double lobe radio source: NGC 5972 classified as an S0-a by Lauberts (1982). We show that it is rather an E galaxy which may possibly be the result of a merger event. It has an emission line spectrum typical of a Seyfert 2 galaxy.
Authors: Veron, P.; Veron-Cetty, M.-P.   
Publication: Astronomy and Astrophysics, v.296, p.315 (A&A Homepage)   
Publication Date: 04/1995   
Origin: CDS; KNUDSEN   
Bibliographic Code: 1995A&A...296..315V   
http://adsabs.harvard.edu/cgi-bin/bib_query?1995A%26A...296..315V

The paper was cited in following paper.:
Title: An Unusual Radio Galaxy in Abell 428: A Large, Powerful FR I Source in a Disk-dominated Host
Authors: Ledlow, Michael J.; Owen, Frazer N.; Keel, William C.
Bibliographic Code: 1998ApJ...495..227L
http://adsabs.harvard.edu/abs/1998ApJ...495..227L

Here is the GZ blog post about the observation by the HST.:
Something rich and strange – Hubble eyes NGC 5972
Quote
(...)This is a galaxy with active nucleus, large double radio source, and the most extensive ionized gas we turned up in the Voorwerpje project. (...)
http://blog.galaxyzoo.org/2012/07/12/something-rich-and-strange-hubble-eyes-ngc-5972/

PS: (...)
« Last Edit: June 19, 2014, 06:23:56 pm by zutopian »