ASTRO: NGC 1055

I posted this one back in my mono days. I thought it looked pretty
good. I decided to redo it in color. See I was very wrong about the
mono image looking good. Never showed either of the odd features of
this galaxy.

NGC 1055 is a member of the M77 (NGC 1068) group. At first glance it
appears much like an ordinary near edge on spiral galaxy. But if you
stretch the image as I've done you notice two obvious features that
aren't common. The first is a tight pair of parallel linear dust lanes
going NW from the core of the galaxy and thus at an angle to the plane
of the galaxy as defined by its massive dust lane. The other, is its
halo. Instead of being round as most are or square as is sometimes seen
in galaxies with a "small" black hole and thus not very massive halo.
the halo of NGC 1055 seems to have gone beyond square to a four pole
shape, a square that is pinched in on all four sides. The argument that
all isn't normal gets stronger when viewed in other frequencies than
visible light. It is strong in radio, especially HI and CO bands, it is
a strong IR emitter as well indicating strong star birth hidden behind a
thick curtain of dust. Its spectrum shows it to be both a Seyfert 2 and
LINER 2 galaxy, both indications of a recent encounter that has stirred
up star formation and is providing food for its core's black hole.

The galaxy is located in Cetus about a half degree from M77. If I had
rotated my camera about 35 degrees east of north I could have just
barely fit both in one frame. Instead I'll refer you to a Robert
Gendler image of the pair at APOD.
http://apod.nasa.gov/apod/ap061215.html

Was M77 involved with a close encounter with NGC 1055? Could be. M77
shows strong signs of a past interaction and is a Seyfert 1 and Liner 2
galaxy. It also has an outer blue ring of stars. All this could be a
sign of past interaction.

APOD puts the group at about 60 million light years from us. I found a
surprisingly large range of values for the distance to these galaxies.
60 million is a bit further than the average but well within the range.
This just shows that we still have a long way to go in pinning down
the true distances to even rather nearby galaxies.

The Sloan image uses three IR bands so shows IR galaxies like this one
as very red rather than its color to our eye. Since I don't use IR
bands in my color data -- my camera is not designed for IR sensitivity
-- I try to color balance as the eye would see it if it were bright
enough for our eyes. Something that can never happen even if we had a
magical space ship that could take us to nearby to the galaxy. That
would make it bigger, not brighter. It would still be too dim to
activate the color sensing cells in our eye.


14" LX200R @ f/10, L=4x10', RGB=2x10'x3, 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".

A lot of detail - I last touched ngc 1055 in 2005- need to add it to
my reshoot list.

At that time I found a paper discussing the 'Boxy-bulge" appearance of
the galaxy and attributing it to infall from a minor merger. The
paper was from a russian team but is no longer available on the ADS
site.

With regard to x-shaped or square bulges, take a look at NGC 128.
The hypothsis is again minor mergers.

Anyhow, good work.

On Tue, 14 Sep 2010 00:36:06 -0500, Rick Johnson
wrote:

I posted this one back in my mono days. I thought it looked pretty
good. I decided to redo it in color. See I was very wrong about the
mono image looking good. Never showed either of the odd features of
this galaxy.

NGC 1055 is a member of the M77 (NGC 1068) group. At first glance it
appears much like an ordinary near edge on spiral galaxy. But if you
stretch the image as I've done you notice two obvious features that
aren't common. The first is a tight pair of parallel linear dust lanes
going NW from the core of the galaxy and thus at an angle to the plane
of the galaxy as defined by its massive dust lane. The other, is its
halo. Instead of being round as most are or square as is sometimes seen
in galaxies with a "small" black hole and thus not very massive halo.
the halo of NGC 1055 seems to have gone beyond square to a four pole
shape, a square that is pinched in on all four sides. The argument that
all isn't normal gets stronger when viewed in other frequencies than
visible light. It is strong in radio, especially HI and CO bands, it is
a strong IR emitter as well indicating strong star birth hidden behind a
thick curtain of dust. Its spectrum shows it to be both a Seyfert 2 and
LINER 2 galaxy, both indications of a recent encounter that has stirred
up star formation and is providing food for its core's black hole.

The galaxy is located in Cetus about a half degree from M77. If I had
rotated my camera about 35 degrees east of north I could have just
barely fit both in one frame. Instead I'll refer you to a Robert
Gendler image of the pair at APOD.
http://apod.nasa.gov/apod/ap061215.html

Was M77 involved with a close encounter with NGC 1055? Could be. M77
shows strong signs of a past interaction and is a Seyfert 1 and Liner 2
galaxy. It also has an outer blue ring of stars. All this could be a
sign of past interaction.

APOD puts the group at about 60 million light years from us. I found a
surprisingly large range of values for the distance to these galaxies.
60 million is a bit further than the average but well within the range.
This just shows that we still have a long way to go in pinning down
the true distances to even rather nearby galaxies.

The Sloan image uses three IR bands so shows IR galaxies like this one
as very red rather than its color to our eye. Since I don't use IR
bands in my color data -- my camera is not designed for IR sensitivity
-- I try to color balance as the eye would see it if it were bright
enough for our eyes. Something that can never happen even if we had a
magical space ship that could take us to nearby to the galaxy. That
would make it bigger, not brighter. It would still be too dim to
activate the color sensing cells in our eye.


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

Rick

Originally Posted by

Rick Johnson wrote:



The quality of your work never ceases to amaze me. Someday it would be
nice to see a list of the equipment and software that was used to get
an image such as this.

Rick

The equipment is in the post.
Software is just CCDSoft to take the image following a script file I write for the evening and using The Sky 6 Pro for telescope control. Both come with the mount. Processing is with Photoshop after calibration in CCDSoft.

Rick