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Old March 17th 14, 09:32 PM posted to alt.binaries.pictures.astro
Stefan Lilge
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Default ASTRO: Pegasus I Galaxy Cluster

Rick,

good that you mentioned the shell because I might have overlooked it
otherwise.
Interesting detail.
And a lot of small spirals to add to the excitement :-)

Stefan

"Rick Johnson" schrieb im Newsbeitrag
...

Two giant elliptical galaxies are at the heart of the Pegasus I galaxy
cluster which is about 160 million light-years distant. NGC 7619 is the
brightest member and likely the most massive but otherwise is a rather
normal elliptical galaxy. The other major member is NGC 7626. It is a
shell galaxy indicating it is the result of a rather recent merger. The
shell is easiest to see on the eastern (left) side. Notes at NED
indicate it has a dust lane at the core though I was unable to find it
in my image. These features as well as others cause it to be classified
as being peculiar. It also has a LINER core, another indication of the
merger that created the shell. Notes also indicate that NGC 7619 likely
harbors a lot of dust areas as well. NGC 7619 is about 180,000 light
years across its major axis. NGC 7626 is slightly larger, about 195,000
light-years. This larger size is likely due to the merger and only
temporary. Both are likely larger than my estimates as determining
where the edges are is difficult though NED gives sizes somewhat smaller
than I'm seeing.

Another rather distorted galaxy in the group is MCG +01-59-058. It is
listed as SB? by NED. It seems a rather normal small spiral except for
that huge faint arm that pushes the main disk way to the east side of
the galaxy making it look "Sloshed". UGC 12510 is listed as E in NED
but I see faint arms making it look like a disk galaxy rather than an
elliptical. Note the apparent bright linear feature in the lower arm is
due to unresolved stars in our galaxy plus a distant background galaxy.
They do add to the spiral appearance. It's best to look to the
northern side where such background and foreground objects are lacking.

In making the annotated image I found nearly all with distance data were
members of the cluster so carry a distance of about 160 million
light-years. For those I omitted writing 0.16 over and over. Only
those obviously not a member have their distance shown. Some rather
bright galaxies had no redshift data. Those are listed with na for not
available. They are likely cluster members but I can't say for sure.

Two asteroids are shown in the annotated image as well.

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

Rick
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