Author Topic: Wednesday, 9 July, 2014: Colors, Spray  (Read 2251 times)

JeanTate

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Wednesday, 9 July, 2014: Colors, Spray
« on: July 09, 2014, 12:47:21 am »
Continuing in the 'good old days' style I used in last week's OOTD (Wednesday, 2 July, 2014: Depth):



This is centered on SDSS J134814.32+152538.1, which has a spectroscopic redshift of 0.057. I'd love to be able to say it - or its northern companion - has been posted before, by ... but I can't!  :'( I do not know how to easily go about finding all the relevant DR7, DR8, and DR9 ObjIds (if I had them, I could search this forum), and even if I did, I do not know how to search GZ Talk for any threads, posts, or comments on any AGZ object/field which may include them.

The bottom half of the northern galaxy (SDSS J134814.77+152550.2) is a very different color than the top half; is that because there's a tidal tail of thick dust across it (and none over the top half)? If so, why isn't the bottom galaxy equally red?

And what's SDSS J134814.58+152541.3, the pure red star in between? Is it just a foreground (Milky Way) very red star (M class perhaps)? or something associated with the merger (heavily reddened)? or ...?

Actually, I couldn't resist including another amazing galaxy:



That's SDSS J011821.34-025856.1, and it was noted by  trevor allen faller_ErrorDupUsername in GZ Talk on December 7 2012 8:17 PM. On July 7 2014 10:45 PM, zooite mendocinosunrise independently discovered it, saying (in GZ Talk) "what are the two jets coming out of the left side of this galaxy?" Super-zooite Budgieye followed up, and noted its resemblance to M82 (see the Bulge or outflow of gas? GZ Talk thread).

Zooite trevor faller posted this here, in the GZ forum, on December 09, 2012, 01:16:14 am: HALO?

Quote from: trevor faller
http://skyserver.sdss3.org/dr8/en/tools/explore/obj.asp?id=1237657065793650763  dont know if this is a foreground irregular with the flat galaxy showing through or a rather large halo

A few hours' later, paulrogers replied:

Quote from: paulrogers
Good question!  And I'll pose another possibility--perhaps it's the remnant dust cloud from a local supernova's planetary nebula that happens to be in our line of sight.

Unfortunately we have no spectra.  If we had separate spectra/redshifts from the eastern blue bit and the southern red bit we could determine if they're the same distance away and associated.  NED gives a single redshift (Redshift:  0.026635 +/- 0.000150) but Skyserver has none.

What do you think?

Oh, more eye-candy; M82 (source):


zutopian

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Re: Wednesday, 9 July, 2014: Colors, Spray
« Reply #1 on: July 09, 2014, 04:40:20 am »
Quote
This is centered on SDSS J134814.32+152538.1, which has a spectroscopic redshift of 0.057. I'd love to be able to say it - or its northern companion - has been posted before, by ... but I can't!  I do not know how to easily go about finding all the relevant DR7, DR8, and DR9 ObjIds (if I had them, I could search this forum), and even if I did, I do not know how to search GZ Talk for any threads, posts, or comments on any AGZ object/field which may include them.

The objIDs in DR8, DR9 and DR10 are identical.
In DR7 the objID is different. In order to find out the corresponding DR7 objID of a DR8/9/10 ID, one can enter the coordinates in DR7, but there are objects, which are just available in DR8/9/10.
All objects, which are available in DR7 are also available in DR8/9/10.
The galaxies in the current Galaxy Zoo are just available in DR8/9/10, but not in DR7. There are few galaxies (in the current GZ), which are also available in DR7, but the reason is, that there is a control sample and besides some objects are stars in DR7, but in DR8 they are galaxies (objtype).

The DR8/9/10-ID of SDSS J134814.32+152538.1 is 11237668313772064831 and it is available in DR7. Here is the link.:
http://cas.sdss.org/dr7/en/tools/explore/obj.asp?id=587742592547160124

« Last Edit: July 09, 2014, 01:11:15 pm by zutopian »

JeanTate

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Re: Wednesday, 9 July, 2014: Colors, Spray
« Reply #2 on: July 09, 2014, 01:22:25 pm »
Thanks zutopian.  :)

DR7 ObjId 587742592547160124 is mentioned in three GZ forum threads (not counting this one): in Biggest cosmic trainwrecks - Mergers on August 19, 2008 by Jouke "Big mess  ;D" (no image posted); in Active galaxies with ionized gas clouds - more denizens of the Zoo on October 03, 2009, by mitch "posted several times before" and an image, also a link to DR7 ObjId 587742592547160123 posted; and in the Nice Merge thread, on February 14, 2009, by Anjin "Always worth a look" (no image posted; Hanny followed up with an image).

DR8 etc ObjId 11237668313772064831 is mentioned in only this thread.

DR7 ObjId 587742592547160123 is mentioned in four GZ forum threads (details later), which seems to be what mitch was referring to.

I haven't yet looked at the ObjIds of the red star.

Any idea how to find the AGZ ID(s) of images which contain any of these galaxies?