ASTRO: Arp 62

Arp 62 was classed by Arp under: Galaxies with small high surface
brightness companions on arms. It is located in Ursa Major about 280
million light-years from us. The CGCG catalog says of the pair: "Pair
of neutral post-eruptive SB and elliptical compact, separation 40"
northeast to southwest." In most catalogs it is listed under one
number. UGC 6865a and b, CGCG 214-035a and b, etc. A is usually the
little companion as it is the westernmost of the two. But the western
one is VV 286b with the main one being VV 286a just to make life more
confusing.

NED classifies the main galaxy as SB, simply a barred spiral with no
attempt to describe the arms. The companion is listed as E(c). I
believe the c is for condensed. At least it sure is. Could be its
outer stars have been stripped from it by the encounter leaving only a
core or it really was this way from the start. I found no papers on
this subject. Shouldn't be hard to tell if the spray of stars contains
a lot of stars similar to those in the small companion. Another case of
too many galaxies and too few telescopes and grad students (translate
that into too little money as well).

In the annotated image there is a lot of galaxies at a distance of about
890 million light-years. Though I found no cluster listed for that
distance. In the upper left corner I've marked a red galaxy as G/GC as
it is the cD galaxy that anchors a galaxy cluster with a given distance
of about 1.6 billion light-years though the galaxy itself has a red
shift of a bit under 1.5 billion light-years. Since it is the anchor
I'd think it's distance should rule but in most of these cases that
doesn't seem to be the case, I don't know why. The cluster is known as
MaxBCG J178.72386+43.60782 and the galaxy as SDSS J115453.73+433628.2.
It is in the 2MASX list as an IR source as well. MaxBCG = Maximum
likelihood redshift Brightest Cluster Galaxy and can identify both the
cluster and the main galaxy in the cluster as it does in this case.
Both the cluster and galaxy carry the same number in this catalog, that
is just its j2000 coordinates. The cluster is listed in NED as having
16 members. The only other cluster member with a given redshift has one
that agrees to the redshift of the anchoring galaxy not that given for
the cluster. There's nothing on the rest in the area.

Another galaxy cluster is in the lower right corner. NSCS
J115213+431915 is listed at 5 billion light-years with some 37 members.
No diameter is listed. The label is located at the center of the
cluster as defined at NED.

Arp's image:
http://nedwww.ipac.caltech.edu/level...big_arp62.jpeg

14" LX200R @ f/10, L=4X10 RGB=2X10X3, STL-11000XM, Paramount ME

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

Rick,

that's a weird specimen indeed. Great detail.

Stefan

"Rick Johnson" schrieb im Newsbeitrag
ster.com...
Arp 62 was classed by Arp under: Galaxies with small high surface
brightness companions on arms. It is located in Ursa Major about 280
million light-years from us. The CGCG catalog says of the pair: "Pair
of neutral post-eruptive SB and elliptical compact, separation 40"
northeast to southwest." In most catalogs it is listed under one
number. UGC 6865a and b, CGCG 214-035a and b, etc. A is usually the
little companion as it is the westernmost of the two. But the western
one is VV 286b with the main one being VV 286a just to make life more
confusing.

NED classifies the main galaxy as SB, simply a barred spiral with no
attempt to describe the arms. The companion is listed as E(c). I
believe the c is for condensed. At least it sure is. Could be its
outer stars have been stripped from it by the encounter leaving only a
core or it really was this way from the start. I found no papers on
this subject. Shouldn't be hard to tell if the spray of stars contains
a lot of stars similar to those in the small companion. Another case of
too many galaxies and too few telescopes and grad students (translate
that into too little money as well).

In the annotated image there is a lot of galaxies at a distance of about
890 million light-years. Though I found no cluster listed for that
distance. In the upper left corner I've marked a red galaxy as G/GC as
it is the cD galaxy that anchors a galaxy cluster with a given distance
of about 1.6 billion light-years though the galaxy itself has a red
shift of a bit under 1.5 billion light-years. Since it is the anchor
I'd think it's distance should rule but in most of these cases that
doesn't seem to be the case, I don't know why. The cluster is known as
MaxBCG J178.72386+43.60782 and the galaxy as SDSS J115453.73+433628.2.
It is in the 2MASX list as an IR source as well. MaxBCG = Maximum
likelihood redshift Brightest Cluster Galaxy and can identify both the
cluster and the main galaxy in the cluster as it does in this case.
Both the cluster and galaxy carry the same number in this catalog, that
is just its j2000 coordinates. The cluster is listed in NED as having
16 members. The only other cluster member with a given redshift has one
that agrees to the redshift of the anchoring galaxy not that given for
the cluster. There's nothing on the rest in the area.

Another galaxy cluster is in the lower right corner. NSCS
J115213+431915 is listed at 5 billion light-years with some 37 members.
No diameter is listed. The label is located at the center of the
cluster as defined at NED.

Arp's image:
http://nedwww.ipac.caltech.edu/level...big_arp62.jpeg

14" LX200R @ f/10, L=4X10 RGB=2X10X3, STL-11000XM, Paramount ME

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