ASTRO: ARP 268/Holmberg II Interesting nearby irregular galaxy

Arp 268/Holmberg II is part of the M81 group and is located about 3 mega
parsecs from us, about 10 million light years. It is classed as a
Magellan type irregular galaxy. Arp classed it under "Galaxies (not
classifiable as S or E); Irregular clumps. That would seem to fit Arp
235 posted earlier as well. Being close and having blue giants up to
19th magnitude I was able to resolve many of its brighter stars and star
clusters. Arp's comment: "Resolution of stars: Note linear loop of
emission regions." I'm not sure how a loop could be called linear but
I'm sure he is referring to that looping feature on the east side (left)
of the galaxy. The CGPG catalog notes: "Large post-eruptive blue
irregular with compact core and many knots." I'm not sure what is
considered the core of this guy. I can't say I see it in any image I
looked at.

There are several interesting galaxies in the field. Above and slightly
left is the oddly red spiral NPM1G +70.0037. I find no distance
estimate. Galaxy Zoo in studying the Sloan Deep Sky Survey images has
discovered a new class of spiral galaxies, red spirals. This may be one
of those. Spiral arms are usually very blue as this is where new star
formation is going on. Without current star formation it was thought
the spiral structure would quickly break down. So this class of spirals
is a real problem to explain.

Down a and to the left of the red spiral is the double galaxy KUG
0815+709. Apparently that bright spot on the upper arm is a second
galaxy. Both it and the red spiral are strong IR emitting galaxies.

Most galaxies in the image are anonymous, including the interesting
looking spiral below the double spiral KUG 0815+709 and the narrow edge
on spiral seen through Arp 236's east side just above that loop of star
forming regions. I'd love to know more about it but couldn't find even
a mention of it anyplace.

There is a large star cluster centered just above my image, RX
J0819.3+7054. Some of its members are seen along the top center of my
image. They are somewhat reddened by their great distance of about 2.7
billion light years. None were listed individually however. Therefore
I can't separate which are cluster members and which are just background
galaxies. Two other clusters are listed in this region to add to the
confusion of who belongs to what.

An excellent image of this galaxy taken by the 10 meter Keck telescope
is at:
http://cse.ssl.berkeley.edu/bmendez/...olmberg_II.jpg

Arp's image of this galaxy is one of his best, indicating a very good
night atop Palomar mountain.
http://nedwww.ipac.caltech.edu/level...ig_arp268.jpeg
Arp's image was taken in blue light it appears to show the super hot
blue stars recently formed in the galaxy.

This was taken January 21 UTC so I'm getting a bit more current in my
processing!

14" LX200R @ f/10, L=4x10' RGB=2x10', 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 Johnson wrote:
Arp 268/Holmberg II is part of the M81 group and is located about 3 mega
parsecs from us, about 10 million light years. It is classed as a
Magellan type irregular galaxy. Arp classed it under "Galaxies (not
classifiable as S or E); Irregular clumps. That would seem to fit Arp
235 posted earlier as well. Being close and having blue giants up to
19th magnitude I was able to resolve many of its brighter stars and star
clusters. Arp's comment: "Resolution of stars: Note linear loop of
emission regions." I'm not sure how a loop could be called linear but
I'm sure he is referring to that looping feature on the east side (left)
of the galaxy. The CGPG catalog notes: "Large post-eruptive blue
irregular with compact core and many knots." I'm not sure what is
considered the core of this guy. I can't say I see it in any image I
looked at.

There are several interesting galaxies in the field. Above and slightly
left is the oddly red spiral NPM1G +70.0037. I find no distance
estimate. Galaxy Zoo in studying the Sloan Deep Sky Survey images has
discovered a new class of spiral galaxies, red spirals. This may be one
of those. Spiral arms are usually very blue as this is where new star
formation is going on. Without current star formation it was thought
the spiral structure would quickly break down. So this class of spirals
is a real problem to explain.

Down a and to the left of the red spiral is the double galaxy KUG
0815+709. Apparently that bright spot on the upper arm is a second
galaxy. Both it and the red spiral are strong IR emitting galaxies.

Most galaxies in the image are anonymous, including the interesting
looking spiral below the double spiral KUG 0815+709 and the narrow edge
on spiral seen through Arp 236's east side just above that loop of star
forming regions. I'd love to know more about it but couldn't find even
a mention of it anyplace.

There is a large star cluster centered just above my image, RX
J0819.3+7054. Some of its members are seen along the top center of my
image. They are somewhat reddened by their great distance of about 2.7
billion light years. None were listed individually however. Therefore
I can't separate which are cluster members and which are just background
galaxies. Two other clusters are listed in this region to add to the
confusion of who belongs to what.

An excellent image of this galaxy taken by the 10 meter Keck telescope
is at:
http://cse.ssl.berkeley.edu/bmendez/...olmberg_II.jpg

Arp's image of this galaxy is one of his best, indicating a very good
night atop Palomar mountain.
http://nedwww.ipac.caltech.edu/level...ig_arp268.jpeg
Arp's image was taken in blue light it appears to show the super hot
blue stars recently formed in the galaxy.

This was taken January 21 UTC so I'm getting a bit more current in my
processing!

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

Rick


------------------------------------------------------------------------

I like the two small ones(upper left), anything known about them?

Sjouke Burry wrote:
Rick Johnson wrote:
Arp 268/Holmberg II is part of the M81 group and is located about 3
mega parsecs from us, about 10 million light years. It is classed as
a Magellan type irregular galaxy. Arp classed it under "Galaxies (not
classifiable as S or E); Irregular clumps. That would seem to fit Arp
235 posted earlier as well. Being close and having blue giants up to
19th magnitude I was able to resolve many of its brighter stars and
star clusters. Arp's comment: "Resolution of stars: Note linear loop
of emission regions." I'm not sure how a loop could be called linear
but I'm sure he is referring to that looping feature on the east side
(left) of the galaxy. The CGPG catalog notes: "Large post-eruptive
blue irregular with compact core and many knots." I'm not sure what
is considered the core of this guy. I can't say I see it in any image
I looked at.

There are several interesting galaxies in the field. Above and
slightly left is the oddly red spiral NPM1G +70.0037. I find no
distance estimate. Galaxy Zoo in studying the Sloan Deep Sky Survey
images has discovered a new class of spiral galaxies, red spirals.
This may be one of those. Spiral arms are usually very blue as this
is where new star formation is going on. Without current star
formation it was thought the spiral structure would quickly break
down. So this class of spirals is a real problem to explain.

Down a and to the left of the red spiral is the double galaxy KUG
0815+709. Apparently that bright spot on the upper arm is a second
galaxy. Both it and the red spiral are strong IR emitting galaxies.

Most galaxies in the image are anonymous, including the interesting
looking spiral below the double spiral KUG 0815+709 and the narrow
edge on spiral seen through Arp 236's east side just above that loop
of star forming regions. I'd love to know more about it but couldn't
find even a mention of it anyplace.

There is a large star cluster centered just above my image, RX
J0819.3+7054. Some of its members are seen along the top center of my
image. They are somewhat reddened by their great distance of about
2.7 billion light years. None were listed individually however.
Therefore I can't separate which are cluster members and which are
just background galaxies. Two other clusters are listed in this
region to add to the confusion of who belongs to what.

An excellent image of this galaxy taken by the 10 meter Keck telescope
is at:
http://cse.ssl.berkeley.edu/bmendez/...olmberg_II.jpg

Arp's image of this galaxy is one of his best, indicating a very good
night atop Palomar mountain.
http://nedwww.ipac.caltech.edu/level...ig_arp268.jpeg
Arp's image was taken in blue light it appears to show the super hot
blue stars recently formed in the galaxy.

This was taken January 21 UTC so I'm getting a bit more current in my
processing!

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

Rick


------------------------------------------------------------------------

I like the two small ones(upper left), anything known about them?

See paragraph 2 and 3 above for all I could find.
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".

Great picture Rick, went straight on my list.

Stefan

"Rick Johnson" schrieb im Newsbeitrag
ster.com...
Arp 268/Holmberg II is part of the M81 group and is located about 3 mega
parsecs from us, about 10 million light years. It is classed as a
Magellan type irregular galaxy. Arp classed it under "Galaxies (not
classifiable as S or E); Irregular clumps. That would seem to fit Arp
235 posted earlier as well. Being close and having blue giants up to
19th magnitude I was able to resolve many of its brighter stars and star
clusters. Arp's comment: "Resolution of stars: Note linear loop of
emission regions." I'm not sure how a loop could be called linear but
I'm sure he is referring to that looping feature on the east side (left)
of the galaxy. The CGPG catalog notes: "Large post-eruptive blue
irregular with compact core and many knots." I'm not sure what is
considered the core of this guy. I can't say I see it in any image I
looked at.

There are several interesting galaxies in the field. Above and slightly
left is the oddly red spiral NPM1G +70.0037. I find no distance
estimate. Galaxy Zoo in studying the Sloan Deep Sky Survey images has
discovered a new class of spiral galaxies, red spirals. This may be one
of those. Spiral arms are usually very blue as this is where new star
formation is going on. Without current star formation it was thought
the spiral structure would quickly break down. So this class of spirals
is a real problem to explain.

Down a and to the left of the red spiral is the double galaxy KUG
0815+709. Apparently that bright spot on the upper arm is a second
galaxy. Both it and the red spiral are strong IR emitting galaxies.

Most galaxies in the image are anonymous, including the interesting
looking spiral below the double spiral KUG 0815+709 and the narrow edge
on spiral seen through Arp 236's east side just above that loop of star
forming regions. I'd love to know more about it but couldn't find even
a mention of it anyplace.

There is a large star cluster centered just above my image, RX
J0819.3+7054. Some of its members are seen along the top center of my
image. They are somewhat reddened by their great distance of about 2.7
billion light years. None were listed individually however. Therefore
I can't separate which are cluster members and which are just background
galaxies. Two other clusters are listed in this region to add to the
confusion of who belongs to what.

An excellent image of this galaxy taken by the 10 meter Keck telescope
is at:
http://cse.ssl.berkeley.edu/bmendez/...olmberg_II.jpg

Arp's image of this galaxy is one of his best, indicating a very good
night atop Palomar mountain.
http://nedwww.ipac.caltech.edu/level...ig_arp268.jpeg
Arp's image was taken in blue light it appears to show the super hot
blue stars recently formed in the galaxy.

This was taken January 21 UTC so I'm getting a bit more current in my
processing!

14" LX200R @ f/10, L=4x10' RGB=2x10', 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".

It certainly deserves a lot more attention than it gets. It also needed
a lot more exposure time than I gave it! So it's still on my list for
next year.

Rick

Stefan Lilge wrote:
Great picture Rick, went straight on my list.

Stefan

"Rick Johnson" schrieb im Newsbeitrag
ster.com...
Arp 268/Holmberg II is part of the M81 group and is located about 3 mega
parsecs from us, about 10 million light years. It is classed as a
Magellan type irregular galaxy. Arp classed it under "Galaxies (not
classifiable as S or E); Irregular clumps. That would seem to fit Arp
235 posted earlier as well. Being close and having blue giants up to
19th magnitude I was able to resolve many of its brighter stars and star
clusters. Arp's comment: "Resolution of stars: Note linear loop of
emission regions." I'm not sure how a loop could be called linear but
I'm sure he is referring to that looping feature on the east side (left)
of the galaxy. The CGPG catalog notes: "Large post-eruptive blue
irregular with compact core and many knots." I'm not sure what is
considered the core of this guy. I can't say I see it in any image I
looked at.

There are several interesting galaxies in the field. Above and slightly
left is the oddly red spiral NPM1G +70.0037. I find no distance
estimate. Galaxy Zoo in studying the Sloan Deep Sky Survey images has
discovered a new class of spiral galaxies, red spirals. This may be one
of those. Spiral arms are usually very blue as this is where new star
formation is going on. Without current star formation it was thought
the spiral structure would quickly break down. So this class of spirals
is a real problem to explain.

Down a and to the left of the red spiral is the double galaxy KUG
0815+709. Apparently that bright spot on the upper arm is a second
galaxy. Both it and the red spiral are strong IR emitting galaxies.

Most galaxies in the image are anonymous, including the interesting
looking spiral below the double spiral KUG 0815+709 and the narrow edge
on spiral seen through Arp 236's east side just above that loop of star
forming regions. I'd love to know more about it but couldn't find even
a mention of it anyplace.

There is a large star cluster centered just above my image, RX
J0819.3+7054. Some of its members are seen along the top center of my
image. They are somewhat reddened by their great distance of about 2.7
billion light years. None were listed individually however. Therefore
I can't separate which are cluster members and which are just background
galaxies. Two other clusters are listed in this region to add to the
confusion of who belongs to what.

An excellent image of this galaxy taken by the 10 meter Keck telescope
is at:
http://cse.ssl.berkeley.edu/bmendez/...olmberg_II.jpg

Arp's image of this galaxy is one of his best, indicating a very good
night atop Palomar mountain.
http://nedwww.ipac.caltech.edu/level...ig_arp268.jpeg
Arp's image was taken in blue light it appears to show the super hot
blue stars recently formed in the galaxy.

This was taken January 21 UTC so I'm getting a bit more current in my
processing!

14" LX200R @ f/10, L=4x10' RGB=2x10', 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".