ASTRO: NGC 185

NGC 185 is a dwarf E3 galaxy that is likely gravitationally bound to NGC
147, another dwarf galaxy. Both are considered satellite galaxies of M
31. NGC 185 is a bit closer to us than M31, probably about 2.3 million
light-years. It is a LINER and Seyfert 2 galaxy with dust clouds near
the core. All this indicates the core has been the scene of recent star
formation. This is born out by the core's rather blue color. Normally
the core of a galaxy is made up of old population II stars which due to
age are usually quite red. Due to lack of star formation for billions
of years only red stars remain. NGC 185 is an obvious exception to this
general rule with a core that contains new, massive, short lived
population I stars.

I managed to image this one on a night of better than average seeing.
It was one taken automatically. I set it up when seeing wasn't all that
great so stayed at my usual 1" per pixel resolution. It could have been
done at 0.5" for more resolution than seen here. One penalty for
imaging while sleeping. Still I was able to resolve many of the new
star clusters in its core and many of the stars throughout the galaxy.
I found an image of the core region taken with one of the Isaac Newton
group's telescopes on La Palma in the Canary Islands. Which one I don't
know but since they range in size from 1 to 4.5 meters and have superb
seeing I thought my image compares quite favorably. I don't see the
core as blue as they do but then I don't see the rest in the odd
greenish yellow color they do either. Their image was taken using
photometric BVR photometric filters rather than those designed for the
color response of our eyes. This may account for the color difference.

NED, while identifying a few galaxies in the field has no red shift data
on any but two that appear to be the same object with different
distances and magnitude estimates. Both are within the error circle for
the other which has 6 times the area of their normal error circle. This
makes identification impossible as I see only near noise level smudges
within that circle. NED shows a quasar without red shift distance which
is very rare. In fact I don't think I've seen that before. The error
circle is huge, 5" of arc. Only stars in that circle are either too
bright by far or a magnitude too faint by my measurement. No filter is
given for the magnitude estimate however.

Isaac Newton Group image:
http://spider.seds.org/spider/LG/Pics/n0185hi.jpg

14" LX200R @ f/10, L=8x10' RGB=2x10'x3, STL-11000XM, Paramount ME

Rick
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Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".