Arp 171 Under much better conditions

Arp 171 and the galaxy cluster it anchors is located about 380 million light-years distant in the northeastern corner of Virgo. I rarely reshoot an object. There are so many new ones yet to explore I usually don't redo something. I made an exception in this case. Partly because the framing the first time missed some interesting galaxies and galaxy clusters to the north and secondly because conditions weren't great the first time so I didn't pick up much of the plumes. I'd hoped to add this data to the earlier image for the area of Arp 171's plumes. Unfortunately the data was so unequal it seemed to hurt the plumes rather than help them so I gave up that attempt. Apparently most of what I thought were plumes were mostly over processed noise in the original image.

Arp 171 consists of the two interacting galaxies IC 1042 and NGC 5718. Both are S0 rather than elliptical galaxies. Though there's some question about this indicated by the ? and : in the two classifications. NGC 5718 is the bright cluster galaxy anchoring the large galaxy cluster SDSS-C4-DR3 1014. Ned shows it with 105 members but gives no size. It certainly is larger than my image.

Arp put this pair under his heading for Galaxies with diffuse counter-tails. Arp's image http://ned.ipac.caltech.edu/level5/A...ig_arp171.jpeg strangely is framed such that most of the plumes lie outside its edges. While the edges of the plumes are rather fuzzy, especially to the northwest I'm quite confident it measures more than 1 million light-years across. I can't recall measuring any coming even close to this size.

For laughs my pathetic first attempt from 2010 is at: http://www.spacebanter.com/attachmen...tid=3403&stc=1

The field is very crowded with annotated objects. In a few cases I've drawn a line to an object when it appears that wasn't necessary, as in the case of the UvES object at 9.45p billion light-years. If you look very closely you will find two objects at these locations with the line going to the one that is labeled. So if a line appears unnecessary or seems off center look closer and you'll find a second object is involved. NED listed quite a few Emission Line Galaxies. They were mostly very faint and hard to see on the processed image. Most were at distances of 4 to 8 billion light-years. Since the image was already rather cluttered I listed only a very few of them to give a sampling of what they are like. I omitted about 100 of these as it would have made the image so cluttered as to be nearly useless.

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

Rick

Rick,

that looks like one giant galaxy with many cores.
Or like a small ghost with widely spread arms :-)

Stefan


"WA0CKY" schrieb im Newsbeitrag ...


Arp 171 and the galaxy cluster it anchors is located about 380 million
light-years distant in the northeastern corner of Virgo. I rarely
reshoot an object. There are so many new ones yet to explore I usually
don't redo something. I made an exception in this case. Partly because
the framing the first time missed some interesting galaxies and galaxy
clusters to the north and secondly because conditions weren't great the
first time so I didn't pick up much of the plumes. I'd hoped to add this
data to the earlier image for the area of Arp 171's plumes.
Unfortunately the data was so unequal it seemed to hurt the plumes
rather than help them so I gave up that attempt. Apparently most of
what I thought were plumes were mostly over processed noise in the
original image.

Arp 171 consists of the two interacting galaxies IC 1042 and NGC 5718.
Both are S0 rather than elliptical galaxies. Though there's some
question about this indicated by the ? and : in the two classifications.
NGC 5718 is the bright cluster galaxy anchoring the large galaxy
cluster SDSS-C4-DR3 1014. Ned shows it with 105 members but gives no
size. It certainly is larger than my image.

Arp put this pair under his heading for Galaxies with diffuse
counter-tails. Arp's image
http://ned.ipac.caltech.edu/level5/A...ig_arp171.jpeg strangely
is framed such that most of the plumes lie outside its edges. While the
edges of the plumes are rather fuzzy, especially to the northwest I'm
quite confident it measures more than 1 million light-years across. I
can't recall measuring any coming even close to this size.

For laughs my pathetic first attempt from 2010 is at:
http://www.spacebanter.com/attachmen...tid=3403&stc=1

The field is very crowded with annotated objects. In a few cases I've
drawn a line to an object when it appears that wasn't necessary, as in
the case of the UvES object at 9.45p billion light-years. If you look
very closely you will find two objects at these locations with the line
going to the one that is labeled. So if a line appears unnecessary or
seems off center look closer and you'll find a second object is
involved. NED listed quite a few Emission Line Galaxies. They were
mostly very faint and hard to see on the processed image. Most were at
distances of 4 to 8 billion light-years. Since the image was already
rather cluttered I listed only a very few of them to give a sampling of
what they are like. I omitted about 100 of these as it would have made
the image so cluttered as to be nearly useless.

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

Rick


--
WA0CKY