ASTRO: Arp 202

Arp 202 is a pair of interacting galaxies about 150 million light-years
from us in southern Lynx. Arp classed them under Galaxies not
classifiable as E or S; Material ejected from nuclei. I'm not sure what
"material" he is referring to. He comments; "Faint tail from small
galaxy". I don't know if this refers to the faint fuzz at the west end
of it or the three objects that trail to the west. The first is just a
star, at least it isn't in the SDSS. The other two are separate
galaxies per the SDSS though no red shift is provided. To me they
appear far distant galaxies though the Kanipe-Webb book consider this
the tail. I see no difference between these two and a third galaxy
directly below the eastern (middle of the three objects) galaxy. Arp
became obsessed with the idea of galaxies ejecting objects and it
appears his opinion of this pair may have colored by this concept.

Arp 202 is composed of two galaxies NGC 2719 and 2719A. Both are
classed as Im pec. The third major galaxy in the image is the nice two
arm spiral, NGC 2724, SAB(s)c, with a red shift that puts it about 5
million light-years further away than Arp 202. Such a difference is
immaterial so it is considered a member of the same group as Arp 202.
There are two small galaxies to its right. The red one has a red shift
indicating a distance of a bit over 1.4 billion light-years. Oddly, the
blue spiral above it isn't in the NED SDSS database. It has hundreds of
far fainter galaxies in this field but not this rather bright one. Nor
could I find any entry for it at NED or SIMBAD.

The small elongated almost double looking galaxy SE of Arp 202 is SDSS
J090028.22+354009.8, also a member of the Arp 202 system. The blue
spindle galaxy NE of Arp 202 is SDSS J090029.38+354840.6 and is also a
member of the Arp 202 group. Half way between Arp 202 and the last
galaxy is a very orange galaxy just above a brighter blue star. This
galaxy is SDSS J090029.38+354840.6 and is about 1.4 billion light-years
distant.

In keeping with the trend that blue is a member of the Arp 202 group and
red isn't we come to SDSS J090043.64+354829.0 directly east of the blue
spindle. It is 1.1 billion light-years away. The relatively large red
spindle NW of Arp 202 is SDSS J085935.91+355242.6 and it is almost 1.4
billion light-years from us as is SDSS J085939.37+355413.7, the round
red galaxy to its north east. The spindle galaxy is very unsymmetrical
with a far fatter and brighter disk to the SE than to the NW of the
core. I wonder what caused that. Is the disk warped so we see it more
face on to the SE or is it really less massive to the NW? Between the
spindle at 1.1 billion light-years and Arp 202, much nearer the former
is another rather bright reddish galaxy. It is SDSS J085943.03+355048.9
at a bit under 1 billion light-years.

I've made an annotated image with the distances in billions of
light-years noted. Several other galaxies and a quasar are in the image
that are also noted on this image besides these I've mentioned. The
interesting thing is that one of the galaxies is actually more distant,
not by much, than one of the the quasars in the image. Both are over 3
billion light years distant. But the quasar at 8.4 billion light years
is a lot further away. Of course Arp likely wouldn't agree and might
say they were emitted by Arp 202 rather recently. The most distant
quasar in the image is also the brightest. This Arp would jump on
instantly. It's red shift puts it at 11.65 billion light years away.
The photons I captured have traveled more than twice the age of our
solar system and possibly longer than our galaxy even existed. In fact
the light left when the universe was only about 2 billion years old. It
boggles the mind to think about.

One of the distant galaxies I've noted but not mentioned yet is SDSS
J090107.85+353657.1 at 1.8 billion light-years near the bottom of the
image. It is a 22nd magnitude galaxy hiding behind a much brighter
star. You may have to enlarge the image to see that there are two
objects there. The galaxy is sticking out of the western side of the
star. Nearby to the NW is SDSS J090121.47+353908.0 at 1.6 billion light
years that appears to be a blue star. But the magnitude and position
exactly match a galaxy in the SDSS so I assume it is correct. Also the
PSF (how the light varies across the object) is typical of a galaxy and
very atypical of the known stars in this part of the image. So
appearances can be deceiving.

Arp's image is at:
http://nedwww.ipac.caltech.edu/level...ig_arp202.jpeg

The Sloan Digital Sky Survey image of Arp 202 is at:
http://astronomerica.awardspace.com/SDSS-18/NGC2719.php

The SDSS image for NGC 2724:
http://astronomerica.awardspace.com/SDSS-18/NGC2724.php
Their filters don't show the color difference between the two galaxies
on its western side that my image shows. They use a different mix of
filters that does alter the color balance from what the eye would see if
it could see such faint color. This helps greatly in their scientific
analysis but does make for sometimes misleading images. Other times the
color is reasonably correct. I've not determined why the variation.

14" LX200R @ f/10, L=4x10' 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".