ARP054

Arp 54 is a pair of galaxies, in Cetus 570 million light-years distant. Arp put in his category for spirals with small, high surface brightness, companions. The main galaxy is MCG-01-07-007 at magnitude 17.1 while the companion is 17.8 magnitude PGC 009107. To me, PGC 009107 is larger compared to the main galaxy than many that Arp put into his category for those with large companions. So is this really the galaxy he meant? It isn't on the arm but well away from it. There is a condensation on the end of the long arm that sort of points to PGC 009107. Is this the companion Arp meant? It better fits the description. But Arp apparently does mean PGC 009107 as the "small" companion as his note reads: "Arm toward companion split, contains nodule." NED classes it as SBc with HII emissions. Some call the pair an M51 type system due to the somewhat straightened arm leading toward the companion.

While it is likely that PGC 009107 is a true companion I found no distance estimates to further prove the relationship.

NED is adding data from the VLT Very Deep Survey. This field is covered. The result is far more objects in my field being identified than normal. I can't begin to label all the galaxies with their distances that are in this image. That would label many hundreds of objects making the annotated image illegible. I did pick those brighter than 21st magnitude in red light within 5 minutes of Arp 54. The number would triple if I went to 22nd magnitude so I had to stop there. Beyond 5 minutes I only picked up ones that caught my eye. Wading through the many thousand entries for this field was more than I felt like attempting. Even with automation, I'd be weeks moving labels so as not to cover up other objects. For the beginners out there the VLT stands for Very Large Telescope which is located on Cerro Paranal, Chile at an elevation of 2635 meters (8645 feet). It should be VLTI as it is an array of 4 8.2 meter telescopes plus four movable 1.8 meter telescopes which can be combined to make very high-resolution interferometric images, far higher than Hubble can achieve. With its 8.2 meter mirrors it gathers over 10 times the light than the 2.5 meter mirror of the Sloan Survey telescope (but with a much narrower field of view). This allows it to pick up far more galaxies in a field it covers than the Sloan Survey does. Too many in my case.

I have some qualms about this survey. Most of the galaxies are star-like in appearance. Even the "close" ones appear to be stars rather than galaxies. It doesn't help that during the L exposures a set screw that has been giving me fits again came loose allowing the left side of the image to defocus. Still I can't tell even the 16th magnitude galaxies seen only in this survey from stars. Are they really galaxies? The redshifts are photographically determined, not spectroscopically. This can be rather accurate for distant galaxies but I've not seen it applied to relatively nearby objects before. Galaxies that do show their true nature are all from the usual catalogs, some are also from this survey as well. But many faint fuzzies were not picked up by this survey which bothers me. There were far too many to note but I did put question marks by a few of them. Others that are quite obvious but without redshift data were left blank. These were from plate surveys or the 2MASS IR survey but not picked up by this new survey. So why did this deep survey miss these obvious galaxies yet pick up so many star-like objects? I just don't know.

I picked up two asteroids, one is known and one is not. Being the image was taken 14 months ago as I type this there's no way to follow up on it. By coincidence, its trail ends at one of the faint fuzzies no survey, even the very deep one, picked up so earned a question mark. EDIT: The unknown asteroid was discovered two years after this was taken and is (401267) 2012 BF133.

Arp's image
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp54.jpeg

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

Related Designations for ARP054

ARP055

Arp 55/UGC 04881 is a pair of interacting galaxies in Lynx about 500 to 540 million light-years distant. Arp put it in his category for spirals with small, high surface brightness companions on their arms. The companion apparently is the galaxy seen against the very west end of the long arm. That galaxy is SDSS J091553.63+441937.4 but NED has no redshift data on it. So no way to know if this is just a line of sight galaxy or truly related. Or wasn't until Hubble imaged it. The HST image clearly indicates the companion is far beyond the colliding spirals as the level of resolution is very different. Arp apparently didn't care that there was no such data. It was appearance he was concerned with. Later astronomers could figure it out. It also appears he didn't realize the "spiral galaxy" is really two interacting galaxies. Or maybe he did but just didn't care. In any case, he never mentions this.

His comment indicates he was likely more interested in the four brightenings in the arm while it was going nearly straight south. It reads: "Arm has four separate condensations in line." I can only see 3 in his image as reproduced. Four are clear in my image, however. NED considers the top one to be a separate galaxy rather than the small bright star cluster it most likely is. Adding to the confusion it appears there's a blue star in our galaxy right on top of the star cloud in Arp 55. To telescopes under our atmosphere, the combination looks a lot fuzzier than it does to the Hubble Space Telescope which clearly resolves the star and star cloud as two separate things separated by a half billion light-years. I don't think Arp understood how common line of sight coincidences like this happen. It also skewed his ideas on quasars. The HST image of this pair can be found at http://hubblesite.org/image/2336/news_release/2008-16 If you can, download the "Highest-quality" 10 meg JPG. NASA puts its distance at a nice round 500 million light-years while redshift data says about 540. I used redshift data from NED for the annotated images.

The long tail and its condensations appear to be due to tidal effects from the collision of these two galaxies. Arp gives no indication he realized this at the time of the atlas. I see NASA refers to this pair as "The Grasshopper" galaxy. Looks more like a shrimp to me. I find no other group using this designation for this or any other galaxy. Seems to be a NASA/HST term. NED makes no attempt to classify the fainter southwestern member and labels the northeastern member with the long tail simply as "spiral" Both are listed as having HII emission which is common with interacting galaxies.

There are several galaxies in the image with the same redshift as Arp 55. It apparently anchors a small galaxy group. One of them, HS 0912+4433, overlaps a second galaxy to the northeast, SDSS J091546.16+442126.7. It has no redshift data. It is much bluer in my image. No way to tell if they are at the same approximate distance or not. They don't appear to be interacting. HS 0912+4433 is classed at NED as a blue condensed galaxy. The neighbor seems bluer and more condensed if they are at about the same distance.

Another, smaller group of galaxies have a redshift that puts them 450 million light-years distant.

There's a galaxy cluster at 5 billion light-years that has the same position (within the 1.5" error circle of the cluster's center) of a faint galaxy. Several others are seen right around it. The cluster is WHL J091538.9+441107. NED shows it having 14 members though no diameter is given. One of the members does have a redshift distance and it too is 5.0 million light years.

To the west and a bit north of Arp 55 is a disk galaxy at 2.4 billion light-years. For it to show that size at that distance it would have to be about 150,000 light-years across. Probably bigger than our galaxy which far above average in size for a spiral galaxy.

I've been asked recently about how big some of these galaxies really are. This is something I give you all enough information to calculate. All my full-size images are at 1" of arc per pixel unless I state otherwise (rare), the enlargements are given as well. Just count the pixels along a major axis and you have its diameter in seconds of arc. The tangent of this multiplied by the distance gives its size. Yes, I know this isn't exactly right. Radius should be used not diameter. The difference, in this case, is 0.00016 light-years! So I do it the faster way not the way your trigonometry teacher would have you do it.

Asteroid (91131) 1998 HX144 to the west of Arp 55 is at an estimated magnitude of 18.3 per the Minor Planet Center. Doesn't seem that bright in my image. The image was taken over two nights. The asteroid was only in the first night's luminance frames. The trail represents 40 minutes of the 80 minutes I spent on the luminance data.

Arp's image with the 200" Palomar Hale telescope:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp55.jpeg

14" LX200R @ f/10, L=8x10' RGB=2x10'x3, STL-11000XM, Paramount ME

Related Designations for ARP055

ARP056

Arp 56 is in Arp's class: Spiral Galaxies with Companions on Arms: Small, high surface brightness companions. It is considered an M51 type system by some. Also, known as UGC 1432, it is located in western Aries. From its very small size, you might think it very distant but it is "only" 350 million light years distant by redshift measurement. I measure the system as being about 90,000 light-years across thanks to the drawn-out arm. Ignoring the arm it is still a respectable 70,000 light-years across. Some papers refer to the bright spot on the end of the arm as a knot. Its color is different from the galaxy so I suspect it is a separate object. While likely it is the cause of the arm I can't find any redshift data for it nor any catalog entry for it.

NED has only one other galaxy's redshift noted in the field. It looks more like a star. Go west (right) from the knot and very slightly down. It is the first object you come to. Quite dim with an even dimmer object just to its left. A smaller, fainter version of a brighter pair a bit further west. It is the IR galaxy 2MASSi J0157210+171248. While very faint in visible light it is 13th magnitude in the infrared K filter. Visible light runs from 4000um (very violet) to about 7000um (deep red). K filters are centered at 22000um or about 3 magnitudes redder than our eyes can see. In my image, it is about 21st magnitude! It is a Seyfert 1 galaxy about 2.6 billion light-years distant. The handful of galaxies NED identifies in the image are all IR galaxies like this one. None have distance or magnitude estimates. Arp made no comment about his one.

Arp's image:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp56.jpeg

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

Related Designations for ARP056

ARP057

Arp 57 is in the southeast corner of Coma Berenices just a few minutes of arc across the border from Virgo. The bottom of the image is in Virgo in fact. It is about 813 million light-years away. Arp put it in his category of spirals with high surface brightness companions on its arm. This time finding the galaxy on the arm is easy as his comment reads: "Small companion connected to end of arm." Or is it easy? Seems there are two galaxies on the end of the arm, a small round blue one followed a bit further out by a larger red oval one. To add to the confusion there's a third one just west of the core of the main galaxy. All are marked on the annotated image. The problem is there's no red shift distance for the two on the end of the arm. The third one no one seems to mention is at the same distance and far closer to the core, at least by line of sight. Or is it just a knot in the spiral arm and not a true galaxy? Then there's the more distant companion also at about the same distance. It doesn't appear distorted so likely hasn't interacted with Arp 57 though obviously is nearby. The two "on" the arm may be as well, I just can't tell. NED makes no attempt to classify any galaxy in the image even the obvious ones.

Edit: Since this was written NED now has a redshift for the galaxy at the end of the drawn-out arm. It shows it to be at the same distance as the spiral galaxy. It is indeed part of the system and likely a true companion. Possibly the cause of the drawn-out arm.

Coverage of this field at NED is hit or miss it appears. In the upper left area of the image three rather bright galaxies aren't in their data base. But below the topmost of the three is a 22.4 magnitude galaxy I've marked that is. Also below these three is a large group of very faint galaxies mostly 22nd and 23rd magnitude. Those I checked are in NED. They appear to be an obvious cluster but NED lists none in this area. Nor does it list a redshift for any in the group -- very frustrating.

A bit above and right of this area is an object at 3.4 billion light-years that is listed in NED as both a Seyfert 1 galaxy and a quasar. Its PSF does fit a point source so likely is a rather close quasar.

This image was taken on a night of far better seeing than normal so was binned 1x1 for a 0.5" per pixel image scale.

Arp's image
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp57.jpeg

14" LX200R @ f/10, L=8x10'x1 RGB=2x10', STL-11000XM, Paramount ME

Related Designations for ARP057

ARP058

Arp 58, UGC 4457 is a bit over a half billion light-years away in the constellation of Cancer, not far from M44, the Beehive Cluster. I tried taking this at 0.5" per pixel but seeing wasn't really up to it so I reduced the image to 0.75" per pixel. Still higher than my normal image scale. Arp classifies this one as a spiral with a small, high surface brightness companion same as Arp 52. His notes say; "...companion on end of broken arm nearly star-like". I'd have to agree. Actually, there may be two galaxies on the arm and the arm appears detached from the galaxy to me. The obvious galaxy on the lower arm segment is LEDA 023937 an E0 elliptical galaxy that appears nearly starlike. What's really odd is that it is blue in color. Ellipticals aren't supposed to be blue as they are usually said to lack the dust and gas needed for new star formation. I could find no explanation for its blue color except one paper saying it's not a galaxy at all (see below). Unlike the also blue companion of Arp 52 which was also blue, this one does have a classification and distance. The distance is the same as UGC 4457 so we know it is a true companion. Complicating things is another galaxy, SDSS J03201.11+291311.9. This is the blue blob just left and slightly up from the blue E0 galaxy. To me, it looks like just the end of the mostly detached spiral arm but it is classed as a separate galaxy, not as part of a galaxy like I'd expect. I also found it referred to as a separate galaxy one reference. It has no classification.

More interesting to me is the very weird blue galaxy toward the upper right corner of my image. It is SDSS J083129.83+191455.2 but I can find no distance or classification data for it. It appears as two very different objects, a compact blue galaxy and a fuzzy arc above it. I find only one designation for it in the Sloan Digital Sky Survey, however. Nor can I find any paper on it. Seems worthy of one or two, at least in my image. Did it too encounter Arp 58? Sure looks distorted and blue like it recently encountered something and that's about all there is in the area.

Back to Arp 58, one paper insists that the arms couldn't have been the result of a tidal interaction. Apparently saying these are HII regions, not separate galaxies at all. No one else seems to agree but it does explain a blue elliptical "galaxy". If that paper is right then that takes me back to that other strange galaxy in the upper right corner as being involved. Where's that Ph.D. candidate looking for a thesis when you want one?

Arp's Palomar 200" telescope image of the galaxies is at:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp58.jpeg

LX200R @ f/10, L=7x10'x1, RGB=2x10'x2, STL-11000XM, Paramount ME

Related Designations for ARP058

ARP059

Arp 59 falls under Arp's classification: Spiral Galaxies with Companions on Arms: Small high surface brightness companions. It is located just under 200 million light years away and is found in the constellation of Cetus. This appears to be a system similar to M51 but with more confused spiral arms. Arp had no comment about this pair. NED has no redshift for the companion to tell if it is a true companion.

The main galaxy is NGC 341, the companion MCG -02-03-064. The little galaxy at the 5 O'clock position is SDSS J010044.49-091151.8. I doubt it is related. I can't tell which arm, north or south, the companion is on. In Arp's photo (south up) the south arm seems to lead to the companion while the north one seems to end at a star to the lower left. In my image, things look just the reverse. The southern arm seems to just suddenly end at the north end of the galaxy or maybe continue and be the blue spike sticking out at the NE While the north arm makes more than a 360 to end in at the companion. Usually, Arp's and my images look much alike but not in this case. It appears it was a night of very poor seeing atop Palomar mountain when Arp took his image. That may explain the differences. The Sloan image doesn't help much that I see. Obviously, the encounter has messed up the arms of NGC 341. NED classes it as SAB(r)bc. It was discovered by Édouard Stephan on October 21, 1881.

As in my image of Arp 19, there appears to be a galaxy cluster just to the east of the galaxy. Though none is shown in NED at that location or any other location within this image. See the enlarged cropped image to see the really faint galaxies in this grouping. I see a few smaller groupings of faint galaxies throughout the image. While the SDSS has apparently cataloged them (I didn't begin to check them all) no redshift distances are provided.

As I've come to expect the SDSS omits blue, low surface brightness galaxies. Is there something about their recognition algorithm that misses them? Or is it a NED selection effect? Maybe it's something else. In any case, the very blue smudge NW of Arp 59 isn't in the over 2000 SDSS galaxies in this image. But it did get picked up by the UK Automated Plate Survey as APMUKS(BJ) B005807.36-092427.4. Is it involved with Arp 59? Its blue color would indicate lots of newly formed massive stars often caused by such interaction. Yet no one seems to have paid it any attention.

This isn't the only somewhat blue galaxy missed by the SDSS and or NED. There's APMUKS(BJ) B005908.94-092242.1 near the left edge above center. It is just below a larger galaxy on the annotated image at 0.71 billion light years. There may be more, I didn't search very hard to find these two. NED picks up 24th magnitude galaxies from the SDSS and misses these 18th magnitude ones.

On the other hand, the very blue sliver of a galaxy in the southeast corner of my image is SDSS J010143.56-091900.7 with a redshift almost identical to that of Arp 59. Could it have tangled with Arp 59 in the past thus causing its new massive stars?

Also on the right edge above center is a very faint blue galaxy the SDSS did pick up at 250 million light years. This galaxy, like Arp 59 appears to have a galaxy cluster to its east that is obviously far beyond it. None have redshift data. Another, somewhat larger, blue galaxy at 250 million light years is found southeast of Arp 59. Are these two related?

The asteroid toward the northeast corner is (123186) 2000 UB9 at magnitude 17.9.

Sloan image:
http://astronomerica.awardspace.com/SDSS-15/NGC341.php

Arp's image:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp59.jpeg

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

Related Designations for ARP059

ARP060

Another twofer deal. I keep finding it interesting that he often finds two entries in one field and other times ignores equally peculiar galaxies in other Arp galaxy fields. The pair is located in the constellation of Coma Berenices. They are located 958 and 979 light-years distant so likely members of the same group.

Arp 60 is left of center and slightly closer by redshift measurement. It is in his category of Spiral galaxies with small, high surface brightness companions on an arm. One of his larger categories. NED had no redshift data on its "companion" so not certain it really is one. Though there is what might be a third arm on that side that is fainter and less well formed as if tidal effects may have helped cause it. While I see no connection between the two in my image or Arp's images, NED says of it; "small, high surface brightness companion on end of arm M51 Type." What do they see that causes this statement? The SDSS shows it both as a galaxy and a quasar! That seems highly questionable. It is also in the 2MASX catalog of infrared sources. I'm not sure it was in any catalog before Arp put it in his atlas. NED only lists it in catalogs that are far newer. Could it be he found it when he added Arp 196 to the atlas? The "companion" is SDSS J131446.02+260629.8. NED shows it in no other catalog. NED doesn't attempt to classify either member of the pair though the main one is clearly a spiral. The other may be S0 or an edge on spiral. I lean to S0.

Arp 196 is likely a real pair of interacting galaxies. Arp put them in his odd category: Material ejected from Nucleus. Does he think one was ejected from the other or both ejected their tidal plumes? Back when the atlas was compiled tidal plumes weren't well understood. Still, I have problems with most galaxies in this category.

Both show severe distortion unlike Arp 60. The smaller, southern member is listed in the 2MASX catalog as an IR source and the SDSS as a galaxy. The pair carry the designation CGPG 1312.2+2623. This catalog dates back to at least 1971 and may have been partly compiled by the time Arp was looking for his peculiar galaxies. Again, NED shows no other catalog entry for the pair that could have existed at the time of the atlas. These would likely be unknown galaxies if not for inclusion in his atlas. The only comment at NED on the pair reads: "In a post-eruptive interconnected pair of neutral compacts. 45 arcsec [south-south-west] of CGPG 1312.2+2623 NED01. Barlike." The northern member also made the PGC catalog as PGC 046054. Other than that it is quite obscure as well. NED makes no attempt to categorize either member.

The annotated image shows three other galaxies that are about the same distance as these two so likely members of the same group.

Arp's image of Arp 60
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp60.jpeg

Arp's image of Arp 196
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp196.jpeg

14" LX200R @ f/10, L=7x10' RGB=2x10'x3, STL-11000XM, Paramount ME

Related Designations for ARP060

ARP061

Arp 61/UGC 3104 falls under Arp's category for spiral galaxies with high contrast companions on an arm. It is located in the constellation of Eridanus. While redshift puts the main galaxy at about 440 million light-years there's no redshift measurement for the companion that I could find. So there's no way to tell for sure that it a companion though it appears likely. Many other galaxies in the image have approximately the same redshift. All are labeled with the catalog name and distance indicated by the redshift in the annotated image. If they are all members of the same group, as appears likely, most of the distance differences are likely due to motions of the various galaxy as they orbit around the group's center of gravity. The apparently nearby MCG +00-12-053 has no redshift data I could find. I assume it is part of the group. UGC 3105 to the east appears to be the most massive galaxy in the group. Its redshift distance is 400 million light-years. Being so massive it likely is rather near the core distance of the group. It is classed as S0-. Arp 61 is Sa.

The nasty star in the lower right corner is 51 Eridani at magnitude 5.2.

This is a retake as the original was awful. Unfortunately, this try wasn't any better as to detail but the color data wasn't quite as cloud damaged.

Arp's image: http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp61.jpeg

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

Related Designations for ARP061

ARP062

Arp 62 was classed by Arp under Galaxies with small high surface brightness companions on arms. It is located in Ursa Major about 280 million light-years from us. The CGCG catalog says of the pair: "Pair of neutral post-eruptive SB and elliptical compact, separation 40" northeast to southwest." In most catalogs, it is listed under one number. UGC 6865a and b, CGCG 214-035a and b, etc. A is usually the little companion as it is the westernmost of the two. But the western one is VV 286b with the main one being VV 286a just to make life more confusing.

NED classifies the main galaxy as SB, simply a barred spiral with no attempt to describe the arms. The companion is listed as E(c). I believe the c is for condensed or possibly compact. At least it sure is. Could be its outer stars have been stripped from it by the encounter leaving only a core or it really was this way from the start. I found no papers on this subject. Shouldn't be hard to tell if the spray of stars contains a lot of stars similar to those in the small companion. Another case of too many galaxies and too few telescopes and grad students (translate that into too little money as well).

In the annotated image there is a lot of galaxies at a distance of about 890 million light-years. Though I found no cluster listed for that distance. In the upper left corner, I've marked a red galaxy as G/GC as it is the cD galaxy that anchors a galaxy cluster with a given distance of about 1.6 billion light-years though the galaxy itself has a redshift of a bit under 1.5 billion light-years. Since it is the anchor I'd think it's distance should rule but in most of these cases that doesn't seem to be the case, I don't know why. The cluster is known as MaxBCG J178.72386+43.60782 and the galaxy as SDSS J115453.73+433628.2. It is in the 2MASX list as an IR source as well. MaxBCG = Maximum likelihood redshift Brightest Cluster Galaxy and can identify both the cluster and the main galaxy in the cluster as it does in this case. Both the cluster and galaxy carry the same number in this catalog, that is just its J2000 coordinates. The cluster is listed in NED as having 16 members. The only other cluster member with a given redshift has one that agrees to the redshift of the anchoring galaxy, not that given for the cluster. There's nothing on the rest in the area.

Another galaxy cluster is in the lower right corner. NSCS J115213+431915 is listed at 5 billion light-years with some 37 members. No diameter is listed. The label is located at the center of the cluster as defined at NED.

Arp's image:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp62.jpeg

14" LX200R @ f/10, L=4X10 RGB=2X10X3, STL-11000XM, Paramount ME

Related Designations for ARP062

ARP063

Arp 63/NGC 2924 is a multiple galaxy in northwestern Leo about 320 million light-years from us. Arp puts it in his category for spiral galaxies with small, high surface brightness companions on its arm. It appears to have two, one at each end. Arp was silent as to which he meant but most sources say it is the western one, PGC 27534. Problem is there's no redshift data on this one while the one at the eastern end, PGC 1990710 has a redshift that does match that of the spiral galaxy. But is its connection only an illusion due to our line of sight or is it real? Are both true companions? To my eye, both show distortions that could indicate they are both interacting with the main galaxy. Many sources list this as a triple galaxy. NED and Seligman classifies the spiral as SB(s)c pec? while the NGC Project says is is Sc/SBc. Only Seligman classifies PGC 1990710 saying it is SB? pec.

The galaxy was discovered by Johann Palisa on March 27, 1886. Somehow he missed the much brighter pair of galaxies that is Arp 129 just to the northeast. Since his position and description matches Arp 63 there's no question he meant Arp 63 rather than 129 as some sources claim.

While nearly all my full-size images (2004x1336 pixels) are displayed at 1" per pixel this one was taken half-frame at 0.5" per pixel and is displayed at that resolution even though the night didn't really support more than about my normal 1" resolution.

Arp's image: http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp63.jpeg

14" LX 200R @ f/10, L=6x10'x1, RGB=2x10'x2, STL-11000XM, Paramount ME

Related Designations for ARP063