ARP230

Polar Ring Galaxy -- Arp 230

Arp 230/IC 51 is a small galaxy about 62 million miles from us in the western end of the constellation of Cetus the sea monster, north of Beta Ceti. Arp put it in his category of galaxies with concentric shells. His comment: "Inner and outer shells visible in direction of axis only." It is now thought to be a polar ring galaxy and the result of a merger of two galaxies sometime in the past. It is quite small even now so these weren't Milky Way size galaxies before the merger. Note in my image that there appears to be some faint debris of the merger to the south-southeast. I suspected it to be just a reflection but moving the scope didn't alter it as it would a reflection so it must be real. I forgot to move it back after the test so it is off center. The galaxy was discovered by Stephan Javelle on August 30, 1892.

The Hubble Space Telescope took a high-resolution image of the core of this galaxy. Colors don't match mine but that could be due to the filters used. I didn't go back to the original data and see what filters were used. For once the image is oriented the same as mine. I see no sign of a double core but they may have merged or are hidden behind our apparently near edge on view. Looks to me like the arms belong to one galaxy while the north-south elongation may reflect the axis of the other galaxy. I'd love to see it in 3D. NED classes it as S0 pec?. It is listed as PRC B-01 in the Polar Ring Catalog.

The field is very uninteresting with little in the way of faint background stars or galaxies. Only one other galaxy has a redshift given. Find the brightest orange star near the upper right corner and go east, left. First, you come to a star with an edge on galaxy just above and right of it. Nearby directly east is 2MASX J00454753-1320157, a rather orange elliptical looking galaxy with a redshift of 1.6 billion light years. The edge on is the anonymous galaxy APMUKS(BJ) B004314.84-133646.7. There's an interesting looking, very blue, galaxy due east of Arp 230 about 60% of the way to the edge. It is yet another anonymous galaxy APMUKS(BJ) B004436.29-134249.9 in that all we have on it is what an automatic plate measuring engine found, mostly position and magnitude. That's the way it goes with this field.

If you enlarge the field about 2x a lot of faint fuzzies start to appear but otherwise, it is a pretty dull field but for Arp 230.

Hubble image:
http://apod.nasa.gov/apod/ap960822.html

Arp's image:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp230.jpeg

14" LX200R @ f/10, L=4x10 RGB=2x10x3, STL-11000XM, Paramount ME

Related Designations for ARP230

ARP231

Arp 231 is a peculiar galaxy system in northwestern Cetus about 250 million light-years away. Arp put it in his category: Concentric Ring Galaxies. Often his categories had little to do with what was going on, rather they were just an attempt to categorize by appearance. Often a category would contain galaxies of very different natures that just happened to look the same. That isn't so much the case with his concentric ring category. These are thought to be caused by the interaction of two or more galaxies. Sharp rings as in this case coming when a small, dense gas-poor galaxy merges with a much larger one with warm dust and gas. Arp 231 appears to be such a system. For a paper showing how such galaxies are created see: http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1988ApJ...331..682H&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.pdf

Arp 231 consists of two parts IC 1575a and IC 1575B divided by a curving dust lane with IC 1525a being the golden colored northern part and IC 1575B the bluer southern part. I suspect, can't prove, the golden IC 1525a would be the compact, dense gas and dust free galaxy and virtually everything else is debris from both plus the large galaxy it is interacting with. The galaxy was discovered by Lewis Swift on September 5, 1896.

Arp's note on the system reads: "Faintest arc extends about 2' S of the nucleus with absorption." Here he missed mentioning an even fainter arc to the west (right) running behind a blue star that extends out even further than the one Arp saw. I've placed the label for Arp 231 beside the western arc's southern end. I saw hints of even more distant ones in the original FITS but so weak they could be noise. In any case, they didn't survive color addition. This one will need more time to decide the issue as I didn't find anything deeper than mine on the net.

While everything indicates this is two interacting galaxies NED seems to disagree. It classifies parts a and b as simply Part of a single galaxy. Though it does show the north part listed as MCG-01-03-002 and the southern as MCG-01-03-003. NED Classifies the system as S0+ pec. No classification is given for either part though the northern part is stated to have the morphology of a dusty elliptical. This even though they give its size as only 12 seconds of arc (that of the golden core). I still think most of what is seen above and below the dust lane is the larger disk galaxy that the small dense elliptical ran into. I found no papers on this system other than a few that mention it in passing as similar to what the authors were studying. Too bad as it appears to be quite interesting.

I took this one over two nights. First night had excellent seeing but very poor transparency that got worse as the imaging went on. Only the luminance data was usable. The second night had good transparency but horrid seeing, three times worse than through the heavy haze of the night before. The result was good detail in the first image and the ability to see deep in the second but with no resolution. Also, I had bright asteroids pass through the image both nights. I ended up using the second night for color (resolution issues not so important) and for the faint outer parts of Arp 231. The first night's luminance was used for everything else including all the stars and other galaxies. This left me with color tracks of two bright asteroids with no luminance track to go with it. I went back and added in the asteroids from the second night to the luminance data rather than eliminate the color trails. One bright asteroid (lower middle) was from the first night. You can see the seeing difference comparing its trail to that of the two from the second night. It is much finer thanks to far better seeing. Since no color data was not usable the first night it has no color trails. Since seeing the second night was poor I took the color data first hoping by the time it got near the meridian seeing would be better for the second run of luminance data. That was not the case, however. But it does explain why the color comes before the luminance trail. The night before I'd waited until the object was closer to the meridian then took luminance on the east side and color on the west but due to the wait fall fog nailed me. I didn't take that chance the second night. Didn't much matter as seeing never did improve. It was taken October 3rd and 4th, 2010 UT.

The first-night asteroid (without color trails) is (9146) Tulikov at magnitude 16.8. It also shows in the lower right corner from the second night. That's how far it moved in 24 hours. The bright asteroid to the lower left of Arp 231 is (21986) Alexanduribe at magnitude 16.9. 4 other fainter asteroids from the second night were lost when I limited that night to showing only the shells and bright obvious asteroids I had noticed before I started searching the data. One fainter one I did notice and thus include is (110618) 2001 TC149 19.1 in the upper left corner.

The naming citation for Alexanduribe reads:
Alexander Tyler Uribe (b. 1990) is a finalist in the 2005 Discovery Channel Young Scientist Challenge (DCYSC), a middle school science competition, for his physical science project. He attends the Willow Creek Middle School, North Lehi, Utah.
Yes, the asteroid name cuts his first name two letters short for some reason.

The naming citation for Tulikov reads:
Composer Serafim Sergeevich Tulikov (b. 1914), People's artist of the U.S.S.R., is the author of many lyrical and patriotic songs that are very popular with the Russian people.

Arp's image:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp231.jpeg

14" LX200R @ f/10, L=8(4)X10' RGB=2X10'X3, STL-11000XM, Paramount ME

Related Designations for ARP231

ARP232

Arp 137/NGC 2914 is the other peculiar galaxy in the image just to the southeast (lower left) of Arp 232. It falls under Arp's category of Elliptical and Elliptical-like Galaxies: Material emanating from elliptical galaxies. It does have a plume of material coming off the south end and a small faint one off the northern end. Arp's image makes it look like there's an odd hook like arm coming off the northern side as well. I don't know which he is referring to. In my image that northern "hook" is seen as a continuous ring-like structure, or is it a one-armed spiral? Also of interest is the very high proper motion of a star near the "bright" star to the east of Arp 137. In Arp's image, it is northwest of the "bright" star while some 45 years or so later it has moved to the south-southwest of it. I've marked it as HPM in the annotated image. William Herschel found this galaxy on March 3, 1786.

Arp 232/NGC 2911 turned out more interesting than I thought it would be when I was looking at the raw data and Arp's image. Arp put it in his category: Galaxies (not classifiable as S or E); Appearance of fission. I really don't see it in either his image or mine but it sure does have some interesting dust lanes. Two linear ones that make an X near the core rather similar to NGC 660 just not as spectacular. Another forms an arc. Could it be the cause of his fission category? Arp did comment on the larger linear dust lane saying "Absorption lane reaching away from galaxy." It barely shows in his image. I don't see the other dust lanes in his image. Note that Dennis Webb's webpage puts this one in the concentric rings category. He tells me that from Arp's notes it was ambiguous which category it belonged in. He thought it looked more like concentric rings was the right category and put it there for the web page. Later researching this one for their book Dennis contacted Arp who told him it belonged in the fission category. That is what the book shows but the webpage hasn't been updated as of the time I am typing this.

Arp 232 is NGC 2911 and is part of a group of galaxies that includes 3 other NGC objects though one is subject to debate. One of the others is also an Arp galaxy as well though I didn't realize it at the time. Nor did I realize it a month later when I took it though that data is not as good so I'm going with this image. It was discovered by William Herschel on March 11, 1784. Like the other one in this image, he found it isn't in either of the Herschel 400 observing programs.

Arp 232 is classed as SA(s)0:pec;Sy LINER by NED and the NGC Project. NED puts it about 155 million light years distant by its red shift. All that dust is very unusual for an S0 galaxy as is the very distorted shape of its outer envelope. While I found nothing on it, it does appear to me it interacted with or ate a companion. Something had to trigger the Seyfert and LINER activity of its nucleus. I didn't see anything indicating it was interacting with Arp 137 but certainly that galaxy has had a run in with some other galaxy to create its southern plume and odd arm structure. Arp 137 is classed as SB(s)ab by NED and and the NGC project. So none of them see the arm as a ring like I was thinking. It's nearly identical red shift puts it at 160 million light years making the separation between the two at about 225 thousand light years if they were at the same distance from us. Close enough I'd suspect some interaction.

To add to the oddities in this image there's a star-like object just off the NE arm of Arp 137. NED identifies it as SDSS J093403.79+100646.8 saying it is part of Arp 137. It isn't a star, that is certain. Its point spread function (how its light is distributed) shows it to have an angular size and not just a point source like a star. But is it truly part of Arp 137? I don't think so. The galaxy shows no hint of star clusters at my resolution. For there to be a single one making this bright blob and for it to be just off the side of the "ring" doesn't seem reasonable. Adding to the confusion NED, while saying it is part of Arp 137 with a redshift of 160 million light years gives this object a redshift that puts it 1.8 billion light years distant. Far beyond Arp 137. NED doesn't say why it ignores this and thinks it's part of Arp 137. Though I've seen a couple cases where the SDSS redshift was apparently very wrong I doubt this is one of them. I don't have a final answer, however.

The tiny blue galaxy NE of Arp 232 is another problem. Some sources say it is NGC 2912. Other sources say NGC 2912 is a duplicate entry for NGC 2914 (Arp 137) The NGC project, however, says NGC 2912 is just a star. I like Dr. Corwin's logic and will go with him and NED saying NGC 2912 is a star. Seligman agrees with Dr. Corwin on this. The star was first recorded by Herman Schultz on April 3, 1870. The PGC records it as PGC 3325919. That leaves this blue galaxy. NED and Seligman say it is PGC 027167. They put it at a redshift distance of 172 million light-years making it a dwarf member of the group. They class it as Im, an irregular dwarf of the Magellanic type. To me, it looks like a very small spiral but that likely is due to my limited resolution.

There are many more minor members of the group as well as one large member, NGC 2919 in the upper left of my image. It shows a lot of interesting detail. NED classes it as SAB(r)b: with a redshift that puts it only 127 million light-years away. Is it truly a member of the group with a somewhat unusual red sift due to its motions in the cluster or just a foreground object. I flipped a mental coin and it came up with it being a member of the group. It was discovered by William Tempel on February 1, 1877. The annotated image lists galaxies that have a redshift indicating they are members of the group listed by catalog name and distance. Galaxies and quasars not members of the group with redshift data are listed by their redshift distance. All distances are in billions of light years and determined using NED's 5 year WMAP option.

Arp 232/NGC 2911 was discovered by William Herschel on March 11, 1784. NGC 2912, just a star, was cataloged by Herman Schultz on April 3, 1870. Arp 137/NGC 2914 was discovered by William Herschel on March 3, 1786. Neither of Herschel's discoveries are in either of the Herschel observing programs. NGC 2919 was discovered by Wilhelm Tempel on February 1, 1877.

If all this isn't enough there are two asteroids in the image also identified on the annotated image. Both are near the top of the image. (51757) 2001 LA4 at magnitude 19.4 is directly above Arp 232 while (78275) 2002 PU30 at magnitude 19.8 is about 3 and a half minutes northeast of it coming out of the right side of a rather bright star.

I've included an SDSS image of this Arp pair. For some reason, it doesn't show the dust lanes of Arp 232 nearly as well as my image yet has higher resolution.

Arp's image of Arp 137 is at:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp137.jpeg

Arp's image of Arp 232 is at:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp232.jpeg

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

Related Designations for ARP232

ARP233

Arp 233/UGC 5720/HARO 02 is a blue compact galaxy in Ursa Major about 75 million light-years distant. It is a starburst galaxy. NED classifies it as Im Pec with HII emission lines. Arp put it in his category Galaxies (not classifiable as S or E): Appearance of Fission, one of his largest categories. He made the comment: "Narrow faint absorption lane in south-following direction." This is likely the reddish band best seen on my enlarged cropped image on the southeast end of the brightest part of the galaxy. The HARO catalog lists blue galaxies with emission lines. It is also MRK 0033 which lists ultraviolet excess sources and SBS 1029+546, a catalog of emission line source. None of this was known when Arp made his atlas.

In my image, the galaxy appears rather noisy due to a grainy appearance. This is likely real as the rest of the image shows no such "noise". Though the SDSS image doesn't seem to show this nor does it show the thin red band that is in my image.

While Arp's image seems to have a hint of a narrow "waist" to the galaxy that may be the reason for his "appearance of fission" classification it really doesn't show in my image. Though I have a blue region to the NE and more white brighter region southeast of it. That could be what is making the two lobe hint to Arp's image. "Appearance of mitosis" seems a more reasonable description to me.

So what caused this starburst activity? It's usually associated with a close encounter with another galaxy. I meant to try and include UGC 5676 in this image. Somehow I made a couple math errors and missed it by a wide margin. This galaxy is highly distorted. I need to go back and image it. Its redshift is virtually the same as Arp 233 making it a likely candidate. It isn't a starburst galaxy but is very blue indicating it has a lot of very young super hot stars which could be caused by an interaction with another galaxy. Certainly, some encounter is responsible for its distortions. While I missed imaging it I've included the SDSS image of it anyway.

But there's yet another candidate. Being about 80 minutes away it may seem too far but these are close galaxies. The distance between the two not much greater than that between M81 and M82 for instance and M81 is usually considered the reason for M82's starburst activity. The galaxy I'm referring to is Arp 217/NGC 3310. I imaged it early in my digital career and severely damaged the color data by stupidity not saving the original so I can't go back and fix it. It is on my re-shoot list, however. I prefer UGC 5676 but needed to mention this one as well.

Arp's image
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp233.jpeg

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

Related Designations for ARP233

ARP234

ARP 234, NGC 3738 is a large irregular galaxy that's a member of the Canes Venatici 1 Cloud though is located in Ursa Major at the bottom of the bowl of the big dipper. Arp classed it in his galaxies with appearance of fission category. As with most in this category, I have no idea what he is seeing. I just see a very blue irregular galaxy with no defined core but a large number of star-forming regions toward the center. I screwed up when taking this image. I knew that NGC 3756 would be in the same field if I put Arp 234 a bit high in the field. But I forgot which side of the meridian I was on. With it west of the meridian the camera is upside down so I should have put it low in the field, not high. The two are completely unrelated but it would have made a more interesting image with a second rather large galaxy in the image. I found many different distance estimates for Arp 235. Most fell in the 11.5 to 15 million light-year range. That would put it just beyond the local group. It was discovered by William Herschel on April 14, 1789. Like so many Arp galaxies he discovered this one too isn't in either of the observing programs for Herschel objects.

The only other galaxy in the image to show much detail is CGCG 268-054 to the NW of Arp 234. It is a 15th magnitude face on spiral at about 390 million light-years away. I sure wish it was closer as it shows some arm structure that looks really interesting. The tiny nearly star-like deep orange galaxy just to its southwest is SDSS J113459.03+543907.5, a 20th magnitude galaxy some 3.8 billion light-years distant. To its northwest making a flat isosceles triangle is a somewhat blue star-like object. It is the quasar SDSS J113455.00+543925.7 at 9.3 billion light-years. Continuing NW about the same distance you come to SDSS J113450.67+543953.0 at 1.8 billion light-years. Seems most objects in this field are rather distant except for Arp 234.

The 17th magnitude barred spiral galaxy west and a bit north of Arp 234, well south of a rather bright star is 2MASX J11344865+5433429 at 1.5 billion light-years.

North and a bit west of Arp 234, between two bright stars, is the red spindle of 2MASX J11344865+5433429, an 18th magnitude galaxy about 1.7 billion light-years distant. The spindle points southeast, just past a blue star to a blue galaxy, SDSS J113549.21+543950.4 at just under 1 billion light-years. Continuing southeast quite a ways brings you to another red spindle SDSS J113621.51+543725.3 also 1.7 billion light-years away. Going Northeast from this red spindle brings you to a rather large and bright blue possible edge on galaxy, SDSS J113644.19+543859.6, at 260 million light-years. A pretty close galaxy for this field! Follow the galaxy's plane to the northeast. You will come to a 19th magnitude blue quasar, SDSS J113722.84+544155.2 about 60% of the way to the upper left corner. It is 11.3 billion light-years distant.

There's an even more distant quasar in the image. Go directly east from Arp 234 almost to the eastern (left) edge. There's a bright blue star there. Just to its east are three "stars" in a flat triangle. The brightest is a bit north of the bright star and is really the galaxy SDSS J113737.23+543211.5. Below it and a bit west is the second brightest of the three. It is the quasar, shining at magnitude 22.0 in green light SDSS J113736.87+543149.5 at 12.2 billion light-years. The fainter, third member to the west and a bit south is the 22.2 magnitude galaxy SDSS J113735.03+543146.9. Makes you wonder if any of the stars in the image really are stars! NED has no redshift data on these two galaxies.

Directly east of Arp 234 a short ways, under a rather bright blue star is the somewhat blue 17th magnitude galaxy, 2MASXi J1136165+543150 at 260 million light-years. Further east and a bit south brings you to another blue spindle, SDSS J113645.38+543034.4 at 270 million light-years. Going north from 2MASXi J1136165+543150 brings you to a bright 17th magnitude blue-white galaxy, 2MASX J11361710+5433537 at about 770 million light-years. Northeast of it is the very red star-like galaxy SDSS J113625.97+543418.8 at 3.6 billion light-years.

Just east of due north of Arp 234, near the top of the image, is the rather bright 17th magnitude disk galaxy, 2MASX J11360396+5442187 which is 1.3 billion light-years distant. NE of it is a tight triangle of 3 objects. The brightest is MAPS-NGP O_130_0297875, below and to its left is the galaxy SDSS J113615.91+544259.4. The third object is really a tight unequal double star if you enlarge the image enough you will see this though at first glance it appears to be a galaxy and had me fooled for a bit. I have no distance estimate for either galaxy. As that's the case with the rest of the hundreds of galaxies in this image I'll stop the tour here.

The annotated image I've attached will help you find the galaxies and quasars mentioned. They are listed by distance in billions of light years. There are some really tiny nearby galaxies that appear smaller than some several billion light-years away. The close ones are really small dwarf galaxies compared to the distant ones.

Imaged April 29, 2009.

SDSS image:
http://astronomerica.awardspace.com/SDSS-27/NGC3738.php

Arp's image:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp234.jpeg

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

Related Designations for ARP234

ARP235

ARP 235/NGC 14 is an irregular peculiar galaxy in Pegasus. Arp classified it under: "Galaxies (not classifiable as S or E); Appearance of fission. He also noted; "Faint outer oval and resolution into stars". Was he referring to all the star clusters in the core of this galaxy? I see nothing else in his photo with the 200" scope that would fit. http://nedwww.ipac.caltech.edu/level5/Arp/Figures/big_arp235.jpeg. Film grain is very obvious in the image but I see no sign of stars. This galaxy is nearby at only about 24 million light years. Therefore some earth based scopes should be able to resolve stars in it using today's detectors. In fact, the star clusters look almost like stars in the Sloan Deep Sky Survey but they are far too bright to be individual stars. It was discovered by William Herschel on September 18, 1786. It's not in either Herschel 400 observing programs.

Toward the lower left corner is a small blue galaxy with an even bluer blob within the halo just right of its core. It too is about 25 million light-years away per its redshift. It is KUG 0007+154. The small blue blob carries the designation of SDSS J000952.87+154406.9 and is listed as a separate galaxy. Both have about the same redshift. Makes me think it is more likely a star-forming region in HUG 0007+154. To be this small at this distance KUG 0007+154 would have to be a very small dwarf galaxy with the possible companion being a subdwarf.

The galaxy above ARP 235 is SDSS J000846.00+155142.2 at 530 million light years. It is very blue and seems to have an off-center core. Yet I see nothing around it that could have caused this.

To the west (right) of Arp 235, a short distance (in my image), is a small red galaxy. This is SDSS J000834.99+155011.8 at 2.07 billion light-years. It has been severely reddened by all the intergalactic dust and gas its light passed through to get to us.

At about 10 o'clock from Arp 235 is a very blue "star" at about the same distance from Arp 235 as the above galaxy. Two stars to its lower left point about at it, the lower of the two is somewhat orange in color. This is the quasar SDSS J000856.79+155045.7 at 9.0 billion light years, the most distant object in the image of which I'm aware.

To the lower left above KUG 0007+154 is the trail of asteroid (93258) 2000 SX165. At a distance of about 18 light minutes, it is the closest object to us in the image. That means the quasar is about 600 trillion times further away than the asteroid! Now that's a large depth of field!

Arp's image: http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp235.jpeg

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

Related Designations for ARP235

ARP236

Arp 236 is a pair of colliding galaxies in southwestern Cetus below my normal -15 degree cut off. Seeing was poor but I had to give it a try. Transparency even worse. My normal limiting magnitude is about 22.5. It is 19.5 here, three below normal. This is why the sky seems so devoid of stars and other galaxies. Conditions such as these are normal this low in my sky, especially this time of the year. Arp put it in his odd category of "Appearance of Fission". Besides IC 1623 he also included IC 1622 to the southwest in his image centering between the two. His comment reads: "Faint outer arm curves around through 270º." I don't really see this arm in Arp's photo but even under my horrid conditions, it does show in mine. Due to the noisy conditions, it is seen better in the full-size image rather than the enlarged cropped image. While he included IC 1622 in his image he makes no mention of it in the atlas. NED shows the distance to IC 1623 as about 260 million light-years and 280 million light-years for IC 1622. So they are likely related.

IC 1623 is considered to be two merging galaxies rather than splitting as Arp's category would indicate. IC 1623A, on the right, is classed as S Pec.? NGC 1623B is not classified. In fact, I can't quite determine which parts belong to which. What about the 2 red blobs in my image? They look much like H alpha not the gold of old core region stars.

Fortunately, the HST has imaged this one. http://hubblesite.org/image/2282/news_release/2008-16

The image is rotated with west up rather than north up in my image. I find the two images somewhat hard to reconcile as to the red blobs. They are separated by a bright region not seen in my image. I believe the low resolution is to blame for some of the problems. If I ever get better seeing down this low I'll have to give it another try. Note too that the HST text puts the pair at 300 million light-years, further than the redshift indicates. They say it will turn into something similar to Arp 220. They make no mention of IC 1622. Both IC 1622 and 1623 were discovered by Lewis Swift on November 19, 1897.

There's very little on this field at NED. The faint fuzzy blue galaxy directly west of Arp 236 is PGC 003973. The lighter blue, smaller galaxy north-northeast of Arp 236 is APMUKS(BJ) B010526.55-174218.1. The somewhat normal looking galaxy near the left edge directly east of Arp 236 is 2MASX J01083536-1729237. None have any distance data. The only other object with redshift data is a star-like object. Go straight north (up) from Arp 236 to near the top. You will see two rather obvious blue stars, the upper is bluer and a bit to the right of perfectly vertical. On either side of it are two orange objects. They make a squat "T". The upper and bluest object is GALEX 2674480679352274903. This tells you it is a strong UV object since that's what the GALEX orbiting telescope studied. It is also listed as XBS J010747.2-172044. This indicates it is an X-ray source as well. It is also listed as a galaxy. It is likely a quasar as well though none of the listings say this. GALEX lists it as an Ultraviolet Excess Source. Most of these turn out to be quasars. NED classes it as an AGN1 galaxy, not a quasar. Just one with a very active nucleus (black hole). But it is so active it is this brightness at the distance of 7.7 billion light-years. That puts it at quasar brightness.

The image contains one asteroid, (188866) 2006 UC150 with a listed estimated magnitude of 19.1. It looks a bit brighter than this to me. It is hard to find. Look southeast (lower left) of Arp 236 about 40% of the way to the corner. It angles down and to the right.

Arp's image
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp236.jpeg

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

Related Designations for ARP236

ARP237

Arp 237 is part of the Hickson 38 galaxy group. It is a 4 galaxy group with Arp 237 being two. The third is the spiral to the southwest. These three are a physical group. The fourth, Hickson 38D to the west-northwest of Arp 237 is a line of sight member of the group being over nearly three times as distant at almost 1.1 billion light-years. The pair constituting Arp 237, UGC 05044 or Hickson 38B and 38C, as well as the third physical member, Hickson 38A, CGCG 062-036 are all about 410 million light-years distant.

NED classes both members of Arp 237 as S? galaxies one place but another says the western member is SBd while the eastern is Im. S? seems more like it to me for both. Arp put them in his class: Galaxies: Appearance of Fission. His comment reads: "Knots in arm as large, not quite as bright as nucleus." I assume he means the two blue knots in the western member (Hickson 38B). Though I don't see them as nearly as bright as the nucleus, even in Arp's blue sensitive image. Though there they are brighter than in my or the SDSS images. The nucleus of the eastern member seems double. The SDSS image hints that this is an illusion and the elongation is a blue star-forming region tight to the core of the galaxy. My color data wasn't sufficient to separate it from the core.

Hickson 38D, the distant member is classed as SBa by NED. It is an IR emitting galaxy cataloged as 2MASX J09273421+1218053. Hickson 38A is listed as Sbc.

This is another field covered by the SDSS that has no redshift data except for the Hickson 38 group itself and a candidate galaxy cluster NSC J092805+122404 at a photographic redshift of about 2.4 billion light-years. You can find it easily west of the bright late G star near the western edge a bit north of Arp 237. There's a lot of faint fuzzies in that area. Though the center position seems off to the NW of what appears the center in my image by a couple minutes of arc. Still, I think this is what it refers to.

There are two asteroids in the image. The brighter and easiest to see is west of Hickson 38A a bit less than 3 minutes of arc and is just beyond a fainter star. That one is (195646) 2002 NN36 at magnitude 19.1. The other is 5 minutes south of Arp 237 just above a faint round galaxy. It is (233778) 2008 TK164. At magnitude 20 it is a bit hard to spot. You will likely have to enlarge the image and possibly brighten your screen to find it. When I have many asteroids in the image I process the image such that they are not reduced in brightness due to being in only one frame of 4 at the same position when the data is combined. This normally reduces their brightness by a factor of 4. When I have a lot of asteroids I use a "lighten" combine that picks up the brightest pixel of each image in the stack. All but the asteroids is then deleted and this pasted on top of the normal combine image. 69That's a lot of work so I didn't do it for this image. I spent the day blowing snow from my 1 km road instead. It's one snow storm after another right now.

Arp's image
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp237.jpeg

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

Related Designations for ARP237

ARP238

Arp 238/UGC 8335 is a pair of galaxies in northeastern Ursa Major about 425 million light-years distant. Arp put it in his category of galaxies with the appearance of fission. Just the opposite of what is likely really happening. His comment is apparently in error. He says: "Double nuclei, north nucleus has third arm." His image is oriented east up. Mine is north up. Hubble's image I've linked to is also east up. In the east up images, there is a third arm from the top (south) galaxy's core. Only 2 from the bottom (north) core. I wonder if Arp thought his image was north up when he made that comment. Normally he marks a V on the images' north side. In this case, the V is on the south side, likely leading to his error. Otherwise, I can't make sense out of it. I never could fathom his fission category either. These are merging not fissioning galaxies. That wasn't understood at his time it appears. He also had one for material ejected from nuclei. Later in life, he decided quasars were ejected from galaxies rather than the active nuclei of galaxies so far away only the accretion disk and possibly the jet from the core can be seen with the galaxy being lost in the glare. Today we have techniques to bring out the hidden galaxy that didn't exist in Arp's day. Still, his theories bordered on (some, would say "were" rather than "bordered on") quackery and got him kicked off the 200" telescope. I can't help but wonder if these categories, fission and ejection are related to this idea. Still, he was using appearance as his guide as no one knew for sure what was going on. His initial purpose for the atlas was to jump-start research into these peculiar galaxies in the hope it would lead to better understanding of how galaxies behave and evolve. He later used it to try and support his quasar ideas. Like Jerry Lewis, he was only appreciated in France. He lives there today last I knew. Edit: Since I wrote this he died December 28, 2013.

The true northern galaxy (upper right in my image) is classed by NED as Sc with a LINER spectrum and a general weak HII emission. Likely this is gas ejected by the encounter and now glowing from the many new super hot blue stars in both galaxies. The southeastern galaxy is also listed as Sc with HII emission but a note at NED says it is mostly in the core and that its core marks it as a starburst galaxy. Not surprising with such a strong interaction going on. NED, however, makes no mention of it being a starburst galaxy.

The full-scale Hubble image makes it appear the third arm is not in the same plane as the others but is headed mostly toward us rather at near right angles to the plane of the other arms. This could be pure illusion but the stars of it are clearly crossing the upper right area of the main disk turning it blue when it otherwise would be rather red in color. The stars of this arm are bluer than the other arms. When I first saw it in my image I thought this excess blue was due to bad color data as a rather bright moon rose while the color was being taken and was quite strong when the blue was taken. This is something I try to avoid but failed to notice at the time. But both Hubble's image and the SDSS confirm this so I didn't let it alter my processing any. I might have had I not had those to check. I gotta learn to trust my data. To me, it appears this "third" arm is really a continuation of the east arm of the northern galaxy seen in front of the southern galaxy. Could the odd stub from the northern nucleus be part of the arm of the southern galaxy? Hard to tell even from the HST image.

Sometimes the inclusions and omissions from the Sloan catalog drive me batty. To give an example I've marked three galaxies in my image that are in the Hubble frame and are very obvious galaxies. Heck in my image I was sure from the PSF of them they were galaxies. None of the 3 are in NED's database which includes the Sloan survey of this field. But a very obscure 22nd magnitude galaxy in the Sloan survey is in the catalog though without redshift data. So how does this faint smudge make it in while far brighter galaxies don't? Wish I knew. Others I'd like to know about like SDSS J131522.78+620741.5 are in the catalog (and marked by name in my annotated image) but are without redshift. Are they related to the other background galaxies I and Hubble picked up that are of about the same angular size? No way to know, unfortunately.

At the top center of the image is the core of a galaxy cluster. NED shows a rather obscure galaxy at its core rather than a huge cD as is normally the case. I've labeled it G/CG followed by the redshift distance of both. While they differ this is more due to rounding than a real difference as the cluster shown at 1.0 is at a redshift of 1.049 and the galaxy shown at 1.053. If I'd have used one more decimal point they'd be the same. The cluster is [YSS2008] 464 ([YSS2008] = Yoon+Schawinski+Sheen [not Charlie]). NED shows it as richness class 4 and gives no diameter. In any case, there are quite a few galaxies with a redshift distance of 1 to 1.1 billion light-years in the image. I suppose most all are considered members or is it just those at the top of the page? Wish I knew.

A second more distant cluster is centered to the top right of my image. It is MaxBCG J198.60277+62.32938 with a membership of 27. It and its anchor galaxy are both 1.7 billion light-years distant. Again no diameter is given. Much of the image contains galaxies at about 1.7 billion light-years that are likely members of the cluster. The SDSS identifies a different center of a galaxy cluster also at 1.7 billion light-years just west of the MaxBCG cluster. Are they the same cluster? NED has no information I can use to determine this. Seems they are likely the same just defined differently. SDSS-C4 3093 is its designation.

Arp's image
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp238.jpeg

Hubble image:
http://www.spacetelescope.org/static/archives/images/large/heic0810al.jpg

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

Related Designations for ARP238

ARP239

Arp 239 is a pair of interacting spirals of the M51 type per notes at NED. It consists of two galaxies, NGC 5279 and 5278 (left to right--east to west). It appears they have a common arm that isn't just a perspective feature, or so several papers indicate. Arp notes "smaller galaxy is fairly symmetric spiral". Oddly that is what it appears to be in his image yet in mine the western arm seems smaller and tighter to the core than the eastern one. Color may have something to do with the different appearance. NGC 5278 appears to be a typical one-armed spiral. As to the common arm, it appears more a tidal blob between two arms than a real arm, at least in my image. A supernova was seen in the western galaxy in 2001.

Arp put this one in his category for galaxies: Appearance of fission. As if he saw this as one galaxy splitting into two. This entire category of 14 entries mystifies me. Did he really think they were splitting? I've never been able to answer that question. William Herschel found the larger galaxy, NGC 5278 on April 14, 1789 but missed the companion. It is too faint to have made either Herschel 400 observing programs. The companion, NGC 5279 was found by his son John Herschel on May 4, 1831.

There was this interesting note at NED: "The main specific feature of this system are (sic) strongly noncoincident positions and radial velocities of the dynamic and photometric centers of both components (3" and 100 km s^-1^ for NGC 5278 and 6" and 20 km s^-1^ for NGC 5279, respectively). A detailed photometric analysis of the system performed by Mazzarella and Boroson (1993) revealed a number of regions or spots of enhanced brightness and the brightest of them is located in the satellite. The strong difference between the dynamic and photometric centers mentioned above may be explained by a similar inhomogeneity of the photometric properties of the two components. The latter may be due, in turn, to the interaction between the galaxies."

Apparently, thanks to the interaction the rotation of the galaxies is no longer centered on the brightest core of each galaxy though it appears there's no agreement exactly where these rotation centers are in the galaxies. In other words, colliding galaxies really make a mess of things until they finally settle down in a few hundred million years.

NGC 5278 is classed as SA(s)b? pec while NGC 5279 is SB(s)a pec. Though some notes class both as Sc. Redshift data is similar for both putting them 350 million light-years distant. They are located in the constellation of Ursa Major, about halfway between Mizar and M101. Mizar-Alcor point right at it for those who want to try and find it visually.

Being in Ursa Major there are a lot of other galaxies in the image. I'll point out just a few of them. Down and right of Arp 239 is UGC 08671 also at 350 million light-years. It seems a bit strange for a spiral and may have been involved in an interaction with another galaxy sometime in the past. To its north, completing the triangle is MCG +09-22-094 at 540 million light-years. Obviously not related to the Arp group. Just to its right is a small IR galaxy SDSS J134115.89+554053.2 at 1.6 billion light-years. Down and to the right is a bright barred spiral with faint looping arms. It is the IR galaxy SDSS J134031.48+553543.4 at 500 million light-years. The tiny red galaxy to its left is SDSS J134043.68+553558.7 at 1.8 billion light-years.

There are a lot of galaxies in the lower left quadrant of my image. The largest and brightest is a rather white elliptical closest to Arp 239. It may be IC 922. NED says its identification is uncertain but gives no details. It is just under 900 million light-years distant. To its left is the tiny compact galaxy SDSS J134305.74+553554.0 at a bit over 900 million light-years. Further left is a much bigger elliptical that could be IC 0923. Again its identification is uncertain. It is about 900 million light-years distant. Above it is an edge on or SO galaxy that may be IC 925 at a bit over 900 million light-years. Again ID is uncertain per NED. This seems to be a broken record as to uncertainty and distance! If you are getting the feeling a galaxy cluster is involved you are right. It is Abell 1783. At least I'm certain about that identification. It has a diameter of 30 minutes of arc and is considered to be centered a bit below and left of the galaxies I did identify. Thus it is mostly out of my frame. NED puts it at a distance of about 920 billion light-years though one note indicates a redshift putting it far closer. That appears unlikely looking at the galaxies that are in my image.

Not all galaxies in the lower left, however, are members of Abell 1783. For instance, the bright somewhat red elliptical near the bottom edge and a bit right of the previous region may be IC 919 at only 480 million light-years. Yep, another uncertain ID. Right beside it to its lower right is the IR galaxy SDSS J134245.98+553107.0 also at 480 million light-years. To their right is the near edge on spiral that might be IC 918 which is about 940 million light-years distant and thus part of the Abell group. Appearances can be deceiving it would appear. I could go on but you get the idea. Instead, I've included an annotated image with these and others noted. Also, there's a second galaxy cluster just beyond the eastern edge of the image which includes IC 926 (ID uncertain -- of course) on the very eastern edge. It is SDSS-C4-DR3 3007 which includes some 33 members. It is centered on IC 929 just east of IC 926. Of course, NED lists its identity as uncertain as well. If I'd have put Arp 239 to the upper right in the image I could have picked up more of both clusters. I didn't realize either were nearby, unfortunately. Note the two quasars in the toward the upper right corner.

Some passing clouds during the blue and one luminosity frame cause moderately bright stars to be somewhat distorted. I tried to tame them as much as possible. I do need to reshoot this under better conditions. Still, the galaxy itself was little bothered by the clouds as its light was totally blocked while they were passing by. The nice thing about not guiding, it saves subs from passing clouds. When clouds hit it doesn't cause the guider to go nuts trying to find the star so picks up right where it left off once the clouds pass.

I've attached a black and white Hubble image made from near IR and UV data. Without visual color data, I didn't try to make a color image out of it. The UV data makes the new star formation very bright. Also since these areas are dusty and that is heated by the new stars these areas were also bright in UV as well. Thus it won't look like my visual light image. The SDSS image includes some IR data so it too is a bit different than my image but without the UV that doesn't get through our atmosphere the new star regions are similar to my shot.

Sorry about the font on the annotated image. Somehow my default got changed to something a bit odd and I didn't catch it in time.

I've also attached a cropped image of just Arp 239 at 0.65 seconds per pixel to better show its details.

Arp's image:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp239.jpeg

14" LX200R@ f/15, L=4x10 RGB=2x10x3, STL-11000XM, Paramount ME

Related Designations for ARP239