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What is this galaxy?



 
 
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  #1  
Old December 27th 16, 10:39 PM posted to sci.astro.research
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Posts: 35
Default What is this galaxy?

Anyone know what kind of galaxy this galaxy might be?

http://skyserver.sdss.org/dr13/en/to...189&dec=13.076

It has a ring around the central bulge, but no apparent black hole
central high intensity region. Looks a little like a polar ring galaxy,
but the ring is within the bulge near the outer radius of the bulge.

Easiest to see if you zoom in 2 clicks, then invert the image. it's
right next to a disrupted galaxy in Virgo Cluster (which can be seen by
zooming out a couple clicks.

Looks like a galaxy without a black hole, unless the small bright knot
to the north is an ejected black hole.

Thanks,

rt

  #2  
Old December 28th 16, 04:45 AM posted to sci.astro.research
jacobnavia
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Default What is this galaxy?

Le 27/12/2016 =E0 22:39, a =E9crit :
Anyone know what kind of galaxy this galaxy might be?

http://skyserver.sdss.org/dr13/en/to...D186.9189&dec=
=3D13.076

It has a ring around the central bulge, but no apparent black hole
central high intensity region. Looks a little like a polar ring galaxy,
but the ring is within the bulge near the outer radius of the bulge.

Easiest to see if you zoom in 2 clicks, then invert the image. it's
right next to a disrupted galaxy in Virgo Cluster (which can be seen by
zooming out a couple clicks.

Looks like a galaxy without a black hole, unless the small bright knot
to the north is an ejected black hole.

Thanks,

rt


Did you read this?

TOO_FEW_GOOD_DETECTIONS DEBLENDED_AT_EDGE PEAKS_TOO_CLOSE=20
DEBLENDED_AS_MOVING MOVED BINNED4 BINNED2 BINNED1 DEBLEND_PRUNED=20
TOO_LARGE NOTCHECKED INTERP COSMIC_RAY DEBLEND_TOO_MANY_PEAKS MANYPETRO=20
NOPETRO NODEBLEND BLENDED EDGE

Click in the "explore" link.
  #3  
Old December 28th 16, 10:23 AM posted to sci.astro.research
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Posts: 9
Default What is this galaxy?

The galaxy is NGC 4435, a.k.a. VCC 1030 and at least a dozen other
names. Its morphology is classified as SBO (plus some other stuff),
which means it's a barred lenticular (or S0) galaxy. If you click on
the Explore link on the SDSS page (your link), and then on the NED
search link, you'll get a lot of information about this galaxy,
including the fact that it appears in some 363 papers (references), all
of which can be accessed via a link. There are also 12 notes, one of
which says, in part "Because of the dust, it is also impossible to
assess the presence of a nucleus".

  #4  
Old January 1st 17, 04:47 AM posted to sci.astro.research
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Default What is this galaxy?

There are also 12 notes, one of
which says, in part "Because of the dust, it is also impossible to
assess the presence of a nucleus".


Doesn't look like dust is blocking view to center, if it is, the
dust is extraordinarily smooth.

It looks like it ran right through the center of the adjacent galaxy,
and lost it's black hole to the larger galaxy, with the stars
continuing on, blowing out into a spherical shell that has the
appearance of a circle.

But sorting out what is really going on would be a challenge. I'll
have to read some of those papers. But it really looks like it's
a galaxy without a central massive BH............and that's unusual
if so. Wonder if one of the papers shows spectroscopy of the central
region, I'll have to check.

Thanks for letting me know to click on the references to see papers.

rt
  #5  
Old January 1st 17, 06:04 PM posted to sci.astro.research
Phillip Helbig (undress to reply)[_2_]
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Posts: 273
Default What is this galaxy?

In article ,
writes:

Doesn't look like dust is blocking view to center, if it is, the
dust is extraordinarily smooth.

It looks like it ran right through the center of the adjacent galaxy,
and lost it's black hole to the larger galaxy, with the stars
continuing on, blowing out into a spherical shell that has the
appearance of a circle.

But sorting out what is really going on would be a challenge. I'll
have to read some of those papers. But it really looks like it's
a galaxy without a central massive BH............and that's unusual
if so. Wonder if one of the papers shows spectroscopy of the central
region, I'll have to check.


Even though most galaxies probably contain central supermassive black
holes, they are not always active. Even if they are, radiation can be
directed in some direction other than towards us and/or can be obscured
by dust. There is no way you can tell just by looking at an SDSS image.
There are probably many images of this galaxy in much higher resolution.
(The interesting thing about SDSS is not its resolution or depth,
neither of which are particularly good (it is a small telescope at a
site which is much worse than the best, exposures are not particularly
long), but rather the fact that it images a large area of the sky and
does so in survey mode, rather than with targeted observations (which
allow one to study only objects which are already known).)
  #6  
Old January 3rd 17, 04:31 AM posted to sci.astro.research
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Posts: n/a
Default What is this galaxy?

On Saturday, December 31, 2016 at 10:47:34 PM UTC-5, wr=
ote:

{snip}

Doesn't look like dust is blocking view to center, if it is, the
dust is extraordinarily smooth.

It looks like it ran right through the center of the adjacent galaxy,
and lost it's black hole to the larger galaxy, with the stars
continuing on, blowing out into a spherical shell that has the
appearance of a circle.


I'm sure you already know this: the images you see on the SDSS site
are heavily processed representations of the actual SDSS data, which
can be downloaded as FITS files (all the way from the raw data to
the nicest cleaned data). Independent survey observations which may
include this galaxy are GALEX (UV), DECaLS (optical), PS1 (optical),
WISE (IR), Akari (IR), IRAS (IR), Planck (microwave), and FIRST
(1.4 GHz). This being a Virgo cluster galaxy, it may have been the
target of dedicated observations by 8-10m class facilities (e.g.
Gemini, Subaru, Keck, VLT, LBT, and GCT), as well the Hubble; if
so, some imaging data may be in the public domain (in the form of
FITS files).

One terrific thing about data - not JPG or PNG images - in the
public domain is that you can download it and do your own processing;
DS9 is great for this (although the User Manual is rather, um,
terse).

But sorting out what is really going on would be a challenge. I'll
have to read some of those papers. But it really looks like it's
a galaxy without a central massive BH............and that's unusual
if so. Wonder if one of the papers shows spectroscopy of the central
region, I'll have to check.


As PH has already noted, showing robustly that a galaxy as massive
as NGC 4435 has no central SMBH could be extraordinarily difficult,
and not just if it's quiescent.

Thanks for letting me know to click on the references to see papers.


You're welcome.
  #7  
Old January 6th 17, 05:06 AM posted to sci.astro.research
Martin Brown
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Posts: 1,707
Default What is this galaxy?

On 01/01/2017 03:47, wrote:
There are also 12 notes, one of
which says, in part "Because of the dust, it is also impossible to
assess the presence of a nucleus".


Doesn't look like dust is blocking view to center, if it is, the
dust is extraordinarily smooth.


Looks can be deceptive! IRAS infrared imaging was used to better
determine its luminosity profile in a paper from 2009 (fig 4 p1995):

http://iopscience.iop.org/article/10...138/6/1990/pdf

Since VCC1030 aka NGC4435 has a detected unresolved point source at its
core in VLA 8GHz radio observations I think it is highly likely that the
SM black hole is still there but the stripping of dust and gas out of
the smaller galaxy by the previous collision has starved it of food.

It looks like it ran right through the center of the adjacent galaxy,
and lost it's black hole to the larger galaxy, with the stars
continuing on, blowing out into a spherical shell that has the
appearance of a circle.


It is dynamically very difficult for this to happen without a 3 body
collision of roughly similar mass objects. But there *is* observational
evidence for a weakly emitting radio point source at the core (ie a BH).

At least one group thinks that some of what we see in this Virgo field
is confused by local galactic cirrus in the line of sight.

http://mnrasl.oxfordjournals.org/con...1/L26.full.pdf

But sorting out what is really going on would be a challenge. I'll
have to read some of those papers. But it really looks like it's
a galaxy without a central massive BH............and that's unusual
if so. Wonder if one of the papers shows spectroscopy of the central
region, I'll have to check.


Having been and had a look at it on CDS Strasbourg I am actually more
interested in the bright linear source with no obvious optical
counterpart that appears on XMM-Newton EPIC at about 10 O'clock from the
emissions of NGC 4438 (or is it an aeretfact)?.

http://cdsportal.u-strasbg.fr/?target=NGC%20%204435

Unfortunately Chandra field of view doesn't include it.

http://chandra.harvard.edu/photo/200...438/index.html

BTW It isn't a good idea to concentrate on the weirdest most twisted
tree that you can find if you want to understand how trees work.

Arp went down that path in an attempt to debunk the Big Bang (and to be
fair found a lot of very curious interacting galaxies as a result)

https://ned.ipac.caltech.edu/level5/..._contents.html

It is ARP120 in that catalogue.

VLT Cosmic Gem's programme observed this pair in 2011 - rather pretty.

https://www.eso.org/public/news/eso1131/

--
Regards,
Martin Brown
  #8  
Old January 18th 17, 06:49 AM posted to sci.astro.research
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Default What is this galaxy?

On Thursday, January 5, 2017 at 8:06:03 PM UTC-8, Martin Brown wrote:
On 01/01/2017 03:47, wrote:


Martin said:
Having been and had a look at it on CDS Strasbourg I am actually more
interested in the bright linear source with no obvious optical
counterpart that appears on XMM-Newton EPIC at about 10 O'clock from the
emissions of NGC 4438 (or is it an aeretfact)?.

http://cdsportal.u-strasbg.fr/?target=NGC%20%204435


I clicked on above link but didn't see the feature you mentioned.
I did see a faint straight line, (asteroid streak?) at maybe 1
oclock and 3 galactic radii away.

Curious about how to see the other image you mentioned, as much to
learn about how to use another viewer as anything.

I'll be careful regarding twisted trees. ;-)

rt
 




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