ASTRO: NGC 1156 A nearby blue dwarf galaxy

NGC 1156 is a nearby Magellanic dwarf galaxy in Aries. While it is
nearby I can't put a very definite number on it's distance. Redshift
would indicate about 8 million light-years. Tully Fisher measurements
say a bit over 20 million light-years. One paper assumes 6 million
light-years, another 25 million light-years. Pick a number!

An amateur processed HST image of this galaxy shows many HII regions
though several ground based papers talk of only two. So I suppose it
wasn't surprising my LRGB image failed to pick up any of the H alpha
emissions associated with the blue star clusters in my image but for a
hint of it near the southwest end of the galaxy. I'll have to add some
H alpha in the filtered data and see if that helps any. The HST image
can be found at:
http://upload.wikimedia.org/wikipedi...-R658GB625.jpg
Big file!

NGC 1156 apparently has an invisible companion, a dark galaxy. These
consist of huge amounts of neutral hydrogen seen only in radio
telescopes but few if any stars. It too seems to be a dwarf galaxy.
Other than that NGC 1156 appears to be traveling alone through space.
http://www.spacedaily.com/reports/Ar...Candidate.html

Only 2 other galaxies in my image have any redshift data so I didn't
prepare an annotated image. The "large" galaxy near the right edge a
bit higher than NGC 1156 is UGC 02442 at about 460 million light-years.
Near the top right are a pair of galaxies, the upper a quite red
spindle. Below it is V Zw 298 also at 460 million light-years. The red
spindle is 2MASX J02584323+2524381, an infra red emitting galaxy. No
redshift data is available for it however.

To the southwest of NGC 1156 is an interesting, apparently very distant,
curving chain of galaxies. They aren't listed at NED so I can't tell you
anything about them.

14" LX200R @ f/10, L=4x10' RGB=2x10'x3, STL-11000XM, Paramount ME

Rick
--
Prefix is correct. Domain is arvig dot net

Rick,

this galaxy looks a lot like NGC 4449, just smaller...

Stefan

"Rick Johnson" schrieb im Newsbeitrag
. com...

NGC 1156 is a nearby Magellanic dwarf galaxy in Aries. While it is
nearby I can't put a very definite number on it's distance. Redshift
would indicate about 8 million light-years. Tully Fisher measurements
say a bit over 20 million light-years. One paper assumes 6 million
light-years, another 25 million light-years. Pick a number!

An amateur processed HST image of this galaxy shows many HII regions
though several ground based papers talk of only two. So I suppose it
wasn't surprising my LRGB image failed to pick up any of the H alpha
emissions associated with the blue star clusters in my image but for a
hint of it near the southwest end of the galaxy. I'll have to add some
H alpha in the filtered data and see if that helps any. The HST image
can be found at:
http://upload.wikimedia.org/wikipedi...-R658GB625.jpg
Big file!

NGC 1156 apparently has an invisible companion, a dark galaxy. These
consist of huge amounts of neutral hydrogen seen only in radio
telescopes but few if any stars. It too seems to be a dwarf galaxy.
Other than that NGC 1156 appears to be traveling alone through space.
http://www.spacedaily.com/reports/Ar...Candidate.html

Only 2 other galaxies in my image have any redshift data so I didn't
prepare an annotated image. The "large" galaxy near the right edge a
bit higher than NGC 1156 is UGC 02442 at about 460 million light-years.
Near the top right are a pair of galaxies, the upper a quite red
spindle. Below it is V Zw 298 also at 460 million light-years. The red
spindle is 2MASX J02584323+2524381, an infra red emitting galaxy. No
redshift data is available for it however.

To the southwest of NGC 1156 is an interesting, apparently very distant,
curving chain of galaxies. They aren't listed at NED so I can't tell you
anything about them.

14" LX200R @ f/10, L=4x10' RGB=2x10'x3, STL-11000XM, Paramount ME

Rick
--
Prefix is correct. Domain is arvig dot net

When I went to process it my first thought was I'd already done it and
this was an accidental duplicate image run. Sometimes happens when I
forget to mark one of on the To-do list. But running through my
collection I found several including 4449 it was similar to. Lots of
these guys out there.

Rick

On 3/21/2012 3:36 PM, Stefan Lilge wrote:
Rick,

this galaxy looks a lot like NGC 4449, just smaller...

Stefan

"Rick schrieb im Newsbeitrag
. com...

NGC 1156 is a nearby Magellanic dwarf galaxy in Aries. While it is
nearby I can't put a very definite number on it's distance. Redshift
would indicate about 8 million light-years. Tully Fisher measurements
say a bit over 20 million light-years. One paper assumes 6 million
light-years, another 25 million light-years. Pick a number!

An amateur processed HST image of this galaxy shows many HII regions
though several ground based papers talk of only two. So I suppose it
wasn't surprising my LRGB image failed to pick up any of the H alpha
emissions associated with the blue star clusters in my image but for a
hint of it near the southwest end of the galaxy. I'll have to add some
H alpha in the filtered data and see if that helps any. The HST image
can be found at:
http://upload.wikimedia.org/wikipedi...-R658GB625.jpg
Big file!

NGC 1156 apparently has an invisible companion, a dark galaxy. These
consist of huge amounts of neutral hydrogen seen only in radio
telescopes but few if any stars. It too seems to be a dwarf galaxy.
Other than that NGC 1156 appears to be traveling alone through space.
http://www.spacedaily.com/reports/Ar...Candidate.html

Only 2 other galaxies in my image have any redshift data so I didn't
prepare an annotated image. The "large" galaxy near the right edge a
bit higher than NGC 1156 is UGC 02442 at about 460 million light-years.
Near the top right are a pair of galaxies, the upper a quite red
spindle. Below it is V Zw 298 also at 460 million light-years. The red
spindle is 2MASX J02584323+2524381, an infra red emitting galaxy. No
redshift data is available for it however.

To the southwest of NGC 1156 is an interesting, apparently very distant,
curving chain of galaxies. They aren't listed at NED so I can't tell you
anything about them.

14" LX200R @ f/10, L=4x10' RGB=2x10'x3, STL-11000XM, Paramount ME

Rick
--
Prefix is correct. Domain is arvig dot net