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ASTRO: Arp 118
Arp 118 reminds me a lot of Arp 244 I imaged two years ago also known as
the Antenna Galaxies http://www.spacebanter.com/attachmen...ntid=576&stc=1 (yes I know it needs reprocessing). Though there are no long tidal tails and only one of the galaxies is a spiral. This pair is nearly 4 times more distant at just under 400 million light years but the left spiral shows the same loop of knots along one edge that NGC 4038, the upper spiral in the antenna galaxies shows. There seems to be glitch in the NGC catalog as the left member of Arp 118 carries two NGC numbers 1141 and 1143. The right member also has two numbers 1142 and 1144. Considering the catalog is supposed to be in right ascension order (at the time compiled - precession has altered things slightly for widely separated galaxies) this shouldn't happen. Unfortunately, the website I used to investigate such errors no longer exits. I haven't tried the Wayback Machine, it probably has the data. Most sources use 1143 and 1144 so I will too. NGC 1143 (right galaxy) is classed as S0 pec (Ring A) and NGC 1144 as S pec (Ring B). Arp though has them under his "Elliptical or Elliptical-like Galaxies close to perturbing spirals". I assume 1143 is the elliptical-like galaxy and 1144 the perturbing spiral. Though it appears to me its the "perturbing spiral" that has been most perturbed. It's arms are wildly distorted and then there's that blue arc of monster star clusters on the side toward the other galaxy. There are two other possible members of this group but they appear to be staying just far enough away not to be distorted -- yet. One is LEDA 1150350 to the upper right of the other two. Just above NGC 1144 (left galaxy) is a near star-like blue galaxy SDSS J025512.06-001032.9 with a red shift distance that puts it at the same distance and thus likely a dwarf member of the group. At the bottom of the image just slightly left of Arp 118 is a small spiral SDSS J025518.00-001824.7 with no distance data. Just to its right is a blue "star". It is listed as a galaxy SDSS J025516.81-001824.1 at a red shift distance of 1.65 billion light years. Obviously not a member of the group! At the very top of the page left of center is a galaxy with two faint loops for arms one above and one below the core. They must be due to some interaction in the past. It is 2MASX J02552344-0000311 but I can find no data on it. The fact it is a 2MASX galaxy means it was found due to its high infrared emission, a sign of possible massive star formation hidden in thick dust clouds. It is just below a trio of rather bright stars, leftmost the brightest. To its right and right against the upper edge is the spiral galaxy MCG +00-08-044 at 545 million light years. There are two asteroids in the image as well though due to my processing to best show the structure of Arp 118 they are rather faintly seen. The one above Arp 118 half way to the top and a bit right of the group is (42989) 1999 TO245 at magnitude 18.6 slightly further right but only slightly higher than Arp 118 is (47716) 2000 DQ25 at magnitude 19.3. Arp's image is at: http://nedwww.ipac.caltech.edu/level...ig_arp118.jpeg 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". |
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ASTRO: Arp 118
One of my favorites! excellent imaging on this one.
Rick Johnson wrote: Arp's image is at: http://nedwww.ipac.caltech.edu/level...ig_arp118.jpeg 14" LX200R @ f/10, L=4x10' RGB=2x10', STL-11000XM, Paramount ME Rick ------------------------------------------------------------------------ -- Adriano http://www.edmar-co.com/adriano/ 34°14'11.7"N |
#3
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ASTRO: Arp 118
Rick, very good detail in the left of the two galaxies. I also like the
galaxy at the upper limit of the picture, amazing how good the spiral structure of this tiny galaxy can be seen in your image. Stefan "Rick Johnson" schrieb im Newsbeitrag ter.com... Arp 118 reminds me a lot of Arp 244 I imaged two years ago also known as the Antenna Galaxies http://www.spacebanter.com/attachmen...ntid=576&stc=1 (yes I know it needs reprocessing). Though there are no long tidal tails and only one of the galaxies is a spiral. This pair is nearly 4 times more distant at just under 400 million light years but the left spiral shows the same loop of knots along one edge that NGC 4038, the upper spiral in the antenna galaxies shows. There seems to be glitch in the NGC catalog as the left member of Arp 118 carries two NGC numbers 1141 and 1143. The right member also has two numbers 1142 and 1144. Considering the catalog is supposed to be in right ascension order (at the time compiled - precession has altered things slightly for widely separated galaxies) this shouldn't happen. Unfortunately, the website I used to investigate such errors no longer exits. I haven't tried the Wayback Machine, it probably has the data. Most sources use 1143 and 1144 so I will too. NGC 1143 (right galaxy) is classed as S0 pec (Ring A) and NGC 1144 as S pec (Ring B). Arp though has them under his "Elliptical or Elliptical-like Galaxies close to perturbing spirals". I assume 1143 is the elliptical-like galaxy and 1144 the perturbing spiral. Though it appears to me its the "perturbing spiral" that has been most perturbed. It's arms are wildly distorted and then there's that blue arc of monster star clusters on the side toward the other galaxy. There are two other possible members of this group but they appear to be staying just far enough away not to be distorted -- yet. One is LEDA 1150350 to the upper right of the other two. Just above NGC 1144 (left galaxy) is a near star-like blue galaxy SDSS J025512.06-001032.9 with a red shift distance that puts it at the same distance and thus likely a dwarf member of the group. At the bottom of the image just slightly left of Arp 118 is a small spiral SDSS J025518.00-001824.7 with no distance data. Just to its right is a blue "star". It is listed as a galaxy SDSS J025516.81-001824.1 at a red shift distance of 1.65 billion light years. Obviously not a member of the group! At the very top of the page left of center is a galaxy with two faint loops for arms one above and one below the core. They must be due to some interaction in the past. It is 2MASX J02552344-0000311 but I can find no data on it. The fact it is a 2MASX galaxy means it was found due to its high infrared emission, a sign of possible massive star formation hidden in thick dust clouds. It is just below a trio of rather bright stars, leftmost the brightest. To its right and right against the upper edge is the spiral galaxy MCG +00-08-044 at 545 million light years. There are two asteroids in the image as well though due to my processing to best show the structure of Arp 118 they are rather faintly seen. The one above Arp 118 half way to the top and a bit right of the group is (42989) 1999 TO245 at magnitude 18.6 slightly further right but only slightly higher than Arp 118 is (47716) 2000 DQ25 at magnitude 19.3. Arp's image is at: http://nedwww.ipac.caltech.edu/level...ig_arp118.jpeg 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". |
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