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Old December 29th 07, 06:08 AM posted to alt.binaries.pictures.astro
Rick Johnson[_2_]
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Default ASTRO: IC 1613 another dwarf galaxy

As should be obvious by now I like these guys. Though I'm running out
of big and bright ones visible from 47N. This one is in the local
group. I could find no consensus on its distance. This is odd since
most references indicate it was used to help calibrate the cephied
variable standard candle. The only one I found with an error bar put it
at 2.38 +/- 0.07 million light years. So I'll go with that one. That
puts it a bit closer than M31. While it is sort of in the general
direction of Andromeda (south nearly 40 degrees in Cetus) it isn't
associated with it that I have found.

This was again taken with my severe ice problem and seeing this low (if
the celestial equator region is low) over the lake put it right into my
area of bad seeing and heavy fogging from ice in the air over the lake.
You could see it rising up off the lake. I binned 3x3 rather than my
usual 2x2 in an effort to get enough signal to work with compared to the
ice. Oddly, while the fogging was severe it was pretty even with not as
much of a gradient problem as I have higher in the sky with less ice to
look through. I don't understand it but sure do appreciate it!
References I saw say there are HII bubbles all over this guy. But I
wasn't able to image but a few in the area to the upper left. Though
there are a lot of hints of pink throughout the horizontal arm. This
may be noise rather than true signal, I just don't know. I was only
able to get 1 frame of color for each color before the fogging go so
severe I had to quit (was hitting 40,000 ADU in 10 minutes which puts
the fog into my non linear range as well as all the details in the
galaxy. That meant my standard galaxy curves wouldn't work and I had to
figure out new ones. One color frame isn't enough for something this
faint. It took 5 nights to get the data I did then the clouds moved in
and have not left since.

Due to the intense fogging this is a rather noisy shot. I was going to
get more data on it this month but the clouds had other ideas It is now
on the way down and will not again be this high in my dark sky until
next fall so this will have to do for this year.

14" LX200R @ f/10, L=7x10' RGB=1x10' all binned 3x3, STL-11000XM,
Paramount ME

Rick
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