ASTRO: NGC 6338 in a large galaxy cluster

NGC 6338 is the cD galaxy anchoring the SDSS-C4-DR3 3152 galaxy cluster.
The cluster contains some 83 members about 400 million light-years
away near the head of Draco. NGC 6338 is classed as an S0 galaxy rather
than elliptical and has a redshift that puts it 370 million light years
distant, somewhat closer than the listed value for the cluster it
anchors. Adding to the confusion NED lists a 6 galaxy NGC 6338 group at
380 million light-years. All this indicates how difficult it is pinning
a distance to a galaxy or group of galaxies.

Just north of NGC 6338 is the galaxy pair of VII Zw 700 that share a
common halo of stars. Redshift puts the brighter core at 430 million
light years. The fainter southern core has no redshift data.

The annotated image shows the distances to the galaxies (G) in the image
in billions of light-years. Normally most are over a billion light
years distant but in this case most are around 400 million but I stuck
with convention. UvES stands for Ultraviolet Excess Source and often
marks probable quasars. Their distances are photographically determined
rather than spectroscopically determined so likely have a larger error
bar. Most labels are immediately right of the object. When this wasn't
possible a line was drawn to the object. Galaxies with names other than
those that just give its position (SDSS, MASX, etc.) are shown. Most
are IC and NGC numbers. The oddball is GIN. Which simply stands for
Galaxy Identification Number. What criterion was used for galaxies to
include is unknown to me. NED used it as the primary designation for
only one galaxy in the field.

This field may have set a record for the number of galaxies with
redshift data. It will be a short lived record. I'm working on one
that will make this one seem lonely by comparison. Also it may have set
a record for galaxies not in NED. Many of the small ones around NGC
6338 aren't even in NED let alone have redshift data, yet several
thousand galaxies are shown for my field, just that some of the brighter
ones aren't there. I don't know why.

While most of the galaxies are nearby and members of the galaxy cluster
some out past 4 billion light-years are to be found with several UvES
objects out beyond 10 and even 11 billion light-years.

14" LX200R @ f/10, L=5x10' 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".