Arp 166

Been traveling to astronomy meetings about the despiking of Arp 192 and
other things. I should be back for the season now so I hope I can catch
up on my image processing as well as other chores I've been lax about
this summer.

Arp 166 is composed of two interacting elliptical galaxies NGC 750 and
NGC 751 (lower). Both are classed E pec though one source says they are
two normal E0 galaxies. While the NGC project classes them as E1 and E
repectively. Red shift data puts them about 225 million light years
away in the constellation of Triangulum. Arp put the pair in his
category; Galaxies (not classifiable as S or E), with difuse elements.
Note the bright short bridge between the two galaxies. Arp didn't
mention this feature however. His only comment refers to a third galaxy
saying "Small spiral at end of plume." The galaxy wasn't catalogued at
the time of Arp's comment. Now it is known as 2MASX J01572652+3314452.
I find little on it however. It is likely unrelated to Arp 166 however.

There are many other galaxies in the field but many of them, other than
the brightest or IR galaxies aren't cataloged at NED. Several though
are NGC objects. At the top of the image, partly out of frame is NGC
761, an SBa galaxy about 218 million light years away so likely related
to those in Arp 166. The double star below it is NGC 766. In the rush
to find and catalog galaxies many such double stars were seen as
galaxies, some single stars as well. Photography has greatly reduced
but not totally eliminated such errrors.

NGC 739 is the S0? galaxy 40% of the way to the upper right corner. It
is about 196 million light years away per red shift data. NGC 736 is
the large elliptical galaxy toward lower right. Notes refer to an outer
halo or pseudo outer ring. Does this include to the odd plume to the
north that spreads out east and west at the top making a ring arc? It's
red shift indicates a distance of about 188 million light years. NE of
it is NGC 738 at 189 mly, a much smaller, elliptical red compact galaxy.
To the southeast of NGC 736 is NGC 740 described as a very red spindle
and classed SBb?. Red shift says 199 mly. Other measurements vary
between 178 and 215 mly with a weighted average of 201 million light
years in good agreement with RS data.

Some of the fainter galaxies of interest include 2MFGC 01479 (2MASS Flat
Galaxy Cataloge) which is 70% of the way from Arp 166 to the 15th
magnitude NGC 739. In K band IR light this little guy shines at
magnitude 14, a full magnitude brighter than NGC 739 in visual light! A
short hop east and a bit north brings you to VI Zw 116 just 6" south of
a star. It is a Red spherical compact galaxy that is also an IR bright
galaxy.

The asteroid north of Arp 166 is (126304) 2002 AX119 at magnitude 18.6.

Arp's image:
http://nedwww.ipac.caltech.edu/level...ig_arp166.jpeg

14" LX200R @ 1/10, L=4x10', RGB=2x10"x3, STL-11000XM, Paramount ME

Besides the full image I've included a 150% enlarged crop of the pair
which shows the bridge between them a bit better than the normal size
image. In also includes the asteroid. VI Zw 116 is at the upper right
edge of the cropped image.

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".

What an interesting galaxy pair.

Madejsky (1991} describes the interaction as a deeply penetrating low
velocity encounter that will result in a complete merger on the
galaxies next closest approach.


On Thu, 05 Aug 2010 16:22:16 -0500, Rick Johnson
wrote:

Been traveling to astronomy meetings about the despiking of Arp 192 and
other things. I should be back for the season now so I hope I can catch
up on my image processing as well as other chores I've been lax about
this summer.

Arp 166 is composed of two interacting elliptical galaxies NGC 750 and
NGC 751 (lower). Both are classed E pec though one source says they are
two normal E0 galaxies. While the NGC project classes them as E1 and E
repectively. Red shift data puts them about 225 million light years
away in the constellation of Triangulum. Arp put the pair in his
category; Galaxies (not classifiable as S or E), with difuse elements.
Note the bright short bridge between the two galaxies. Arp didn't
mention this feature however. His only comment refers to a third galaxy
saying "Small spiral at end of plume." The galaxy wasn't catalogued at
the time of Arp's comment. Now it is known as 2MASX J01572652+3314452.
I find little on it however. It is likely unrelated to Arp 166 however.

There are many other galaxies in the field but many of them, other than
the brightest or IR galaxies aren't cataloged at NED. Several though
are NGC objects. At the top of the image, partly out of frame is NGC
761, an SBa galaxy about 218 million light years away so likely related
to those in Arp 166. The double star below it is NGC 766. In the rush
to find and catalog galaxies many such double stars were seen as
galaxies, some single stars as well. Photography has greatly reduced
but not totally eliminated such errrors.

NGC 739 is the S0? galaxy 40% of the way to the upper right corner. It
is about 196 million light years away per red shift data. NGC 736 is
the large elliptical galaxy toward lower right. Notes refer to an outer
halo or pseudo outer ring. Does this include to the odd plume to the
north that spreads out east and west at the top making a ring arc? It's
red shift indicates a distance of about 188 million light years. NE of
it is NGC 738 at 189 mly, a much smaller, elliptical red compact galaxy.
To the southeast of NGC 736 is NGC 740 described as a very red spindle
and classed SBb?. Red shift says 199 mly. Other measurements vary
between 178 and 215 mly with a weighted average of 201 million light
years in good agreement with RS data.

Some of the fainter galaxies of interest include 2MFGC 01479 (2MASS Flat
Galaxy Cataloge) which is 70% of the way from Arp 166 to the 15th
magnitude NGC 739. In K band IR light this little guy shines at
magnitude 14, a full magnitude brighter than NGC 739 in visual light! A
short hop east and a bit north brings you to VI Zw 116 just 6" south of
a star. It is a Red spherical compact galaxy that is also an IR bright
galaxy.

The asteroid north of Arp 166 is (126304) 2002 AX119 at magnitude 18.6.

Arp's image:
http://nedwww.ipac.caltech.edu/level...ig_arp166.jpeg

14" LX200R @ 1/10, L=4x10', RGB=2x10"x3, STL-11000XM, Paramount ME

Besides the full image I've included a 150% enlarged crop of the pair
which shows the bridge between them a bit better than the normal size
image. In also includes the asteroid. VI Zw 116 is at the upper right
edge of the cropped image.

Rick

Rick,

there's a bucket full of interesting galaxies in this image. Great shooting.

Stefan

"Rick Johnson" schrieb im Newsbeitrag
. com...
Been traveling to astronomy meetings about the despiking of Arp 192 and
other things. I should be back for the season now so I hope I can catch
up on my image processing as well as other chores I've been lax about
this summer.

Arp 166 is composed of two interacting elliptical galaxies NGC 750 and
NGC 751 (lower). Both are classed E pec though one source says they are
two normal E0 galaxies. While the NGC project classes them as E1 and E
repectively. Red shift data puts them about 225 million light years
away in the constellation of Triangulum. Arp put the pair in his
category; Galaxies (not classifiable as S or E), with difuse elements.
Note the bright short bridge between the two galaxies. Arp didn't
mention this feature however. His only comment refers to a third galaxy
saying "Small spiral at end of plume." The galaxy wasn't catalogued at
the time of Arp's comment. Now it is known as 2MASX J01572652+3314452.
I find little on it however. It is likely unrelated to Arp 166 however.

There are many other galaxies in the field but many of them, other than
the brightest or IR galaxies aren't cataloged at NED. Several though
are NGC objects. At the top of the image, partly out of frame is NGC
761, an SBa galaxy about 218 million light years away so likely related
to those in Arp 166. The double star below it is NGC 766. In the rush
to find and catalog galaxies many such double stars were seen as
galaxies, some single stars as well. Photography has greatly reduced
but not totally eliminated such errrors.

NGC 739 is the S0? galaxy 40% of the way to the upper right corner. It
is about 196 million light years away per red shift data. NGC 736 is
the large elliptical galaxy toward lower right. Notes refer to an outer
halo or pseudo outer ring. Does this include to the odd plume to the
north that spreads out east and west at the top making a ring arc? It's
red shift indicates a distance of about 188 million light years. NE of
it is NGC 738 at 189 mly, a much smaller, elliptical red compact galaxy.
To the southeast of NGC 736 is NGC 740 described as a very red spindle
and classed SBb?. Red shift says 199 mly. Other measurements vary
between 178 and 215 mly with a weighted average of 201 million light
years in good agreement with RS data.

Some of the fainter galaxies of interest include 2MFGC 01479 (2MASS Flat
Galaxy Cataloge) which is 70% of the way from Arp 166 to the 15th
magnitude NGC 739. In K band IR light this little guy shines at
magnitude 14, a full magnitude brighter than NGC 739 in visual light! A
short hop east and a bit north brings you to VI Zw 116 just 6" south of
a star. It is a Red spherical compact galaxy that is also an IR bright
galaxy.

The asteroid north of Arp 166 is (126304) 2002 AX119 at magnitude 18.6.

Arp's image:
http://nedwww.ipac.caltech.edu/level...ig_arp166.jpeg

14" LX200R @ 1/10, L=4x10', RGB=2x10"x3, STL-11000XM, Paramount ME

Besides the full image I've included a 150% enlarged crop of the pair
which shows the bridge between them a bit better than the normal size
image. In also includes the asteroid. VI Zw 116 is at the upper right
edge of the cropped image.

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".