Thread: ASTRO: NGC 6384
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Old July 31st 12, 08:36 AM posted to alt.binaries.pictures.astro
Rick Johnson[_2_]
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Default ASTRO: NGC 6384

NGC 6384 is a low surface brightness galaxy in Ophiuchus about 80
million light-years away. Not a constellation in which you find many
nice spiral galaxies! It is more the globular cluster constellation.
It is also the Zodiac constellation astrologers ignore. NED classes it
as SAB(r)bc and as a LINER galaxy. The NGC Project using a different
classification scheme says SBbc I. It is somewhat obscured and of low
surface brightness making it a bit of a challenging target. I didn't
try to correct the color for reddening. Due to it being somewhat
obscured by our galaxies dust. Looking at various color images on the
net I find it in a field of far more blue stars than I show. I can't
explain the difference but it could be from adjusting the blue back into
the galaxy but not excluding the unobscured stars from this blue boost.
I used the simple G2V balancing of the unobscured stars. This likely
left the galaxy too red due to extinction.

Being in a heavily obscured area of the sky it is not covered by the
Sloan survey. Only 6 galaxies are listed in NED as being in this field,
none with any distance data but NGC 6384 itself.

Several papers indicated the arms were smooth and featureless. That
certainly isn't the impression I got in my image so I had to do some
digging. I found a great Hubble Space Telescope image of it that
certainly doesn't show the arms as smooth and featureless. Also several
papers indicated there was no star formation going on in the core.
Strange as most theories on barred spirals say the bar funnels in gas
and dust triggering star formation around the core area. The text with
the Hubble image says that they see star formation around the core area
triggered by dust and gas that is being funneled into the core. Odd the
experts can't seem to agree on what's going on in this much studied
galaxy. The HST image and text is at:
http://www.spacetelescope.org/images/potw1108a/

I'll let their webpage fill in the details sparse as they are.

14" LX200R @ f/10, L=4x10' RGB=2x10', STL-11000XM, Paramount ME

Rick
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