ARP031

Arp 31/IC 167 made Arp's list under the category for spiral galaxies resembling the integral sign. It is the first of 6 in this category. UGC 3697 is usually referred to as the integral sign galaxy but isn't one of the 6 Arp put in his integral sign category.

To me, Arp 31 is just a wide two arm galaxy showing a short bar. It is located in western Aries about 120 million light-years from us by redshift. It was discovered on January 4, 1889 by Guillaume Bigourdan. It is classified as SAB(s)c.

The other major galaxy in the image is below Arp 31 and to the right. It is NGC 691, an SA(rs)bc galaxy. It is about 110 million light-years distant by redshift and 120 million light years by Tully-Fisher measurements so may be related to Arp 31. It was discovered by William Herschel on November 13, 1786 by William Herschel but isn't in either of the Herschel 400 programs.

Lesser galaxies are IC 1730 to the far upper right. It is listed as a, S0?? galaxy at 120 million light-years so again possibly related to the others. It was first seen by Stephane Javelle on January 17, 1896.

At the top center above Arp 31 is NGC 694 an S0? Pec starburst galaxy. It too, is 120 million light-years distant. It was discovered by Heinrich d'Arrest on December 2, 1861.

Arp's image: http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp31.jpeg

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

Related Designations for ARP031

ARP032

ARP 32, UGC 10770 was classified by Arp as one of six spiral galaxies of the "Integral Sign" type. By this he meant it somewhat resembles the calculus symbol of that name, +" is the closest I can do with Unicode but lean it over a bit. Usually, it is due to a spiral seen at just the right angle but this case is different. It is two colliding galaxies. While these look very small and distant that is misleading. They are really two very small dwarf galaxies that are rather close as galaxies go at about 55 million light years. About the same distance as the many galaxies of the Virgo Cluster. So these are two very tiny galaxies. Star formation, triggered by their collision has turned both of them very blue. The PGC lists the two galaxies separately with the southern one being PGC 59804 and the northern, PGC 59862. Given a distance of about 55 million light-years, the southern galaxy is about 20,000 light-years across and the northern about 15,000. There's a star from our own galaxy that just happens to be right at the point where the two galaxies appear to touch each other. It makes a rather nice pseudo nucleus making the two galaxies appear as one. There are very few images of this pair to be found anyplace on the net. An image of it from the Sloan Digital Sky Survey can be found at:
http://cas.sdss.org/dr6/en/tools/places/page5.asp
It's the third down in the left column. Color has been severely enhanced in this image to bring out subtle color differences. My shot is more in line with the colors the eye would see if the scene were bright enough to trip our color cells in the retina. Seeing was rather poor the night I took this so things are a bit fuzzy.

Arps image: http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp32.jpeg

14" LX200R @ f/10, L=6x10' RGB=2x10x3, STL-11000XM, Paramount ME

Related Designations for ARP032

ARP033

Arp 33 and 326

Another twofer deal on Arp Atlas entries. Most of them are completely unrelated objects that happen to be in the same field. Not this time. Arp 33 is part of Arp 326. Arp 326 is in Arp's category, Galaxy groups, chains of galaxies. The chain is located in Virgo right near the southwestern corner of Bootes. As can be seen in the annotated image this isn't a real chain but consists of galaxies of at least 2 different groups. Since redshift data is available for only 3 of the 7 galaxies Kanipe and Webb consider part of the chain its hard to determine what is really going on here. The chain members, as defined by Kanipe and Webb are (from north to south):

MAPS-NGP O_559_0677185 530 mly
CGCG 045-052, Spiral at 530 mly
SDSS J133727.40+063044.4 Not in Webb/Knipe's list
MAPS-NGP O_559_0677872
UGC 08610, Sa at 530 mly
MAPS-NGP O_559_0792305 520 mly
ARP 33/UGC 08613, SB at 340 mly
LEDA 214126, E? 340 mly

The classification of LEDA 214126 seems way off, Looks pretty much a spiral to me. For this reason, I left the classification off of the annotated image. UGC 08596 at 320 million light-years, classed as simply S and UGC 08623 classed as Sd at 340 million light-years. It is seen edge-on and is extremely flat. So flat it made the Flat Galaxy Catalog. It would appear these two are likely members of the same group as Arp 33/UGC 08613. Why Kanipe and Webb left out SDSS J133727.40+063044.4 I don't know. It is slightly brighter than MAPS-NGP O_559_0677872 just below it. While I identified MAPS-NGP O_559_0682366 NED had little on it. Just seemed big and bright enough to deserve mention. It looks like a nice face on spiral but NED omits a classification for it.

This brings us to Arp 33. While a member of the Arp 326 "chain" it made the Atlas under the Integral Sign category. It is a bit better integral sign than most of the others in that category, some of which require a lot of imagination to see as that math symbol. NED considers Arp 33 to also include LEDA 214126 which is also part of the Arp 326 group. Arp did include it in his image of Arp 33. The VV catalog considers UGC 08613 to be 4 galaxies; VV 6a through VV 6d. NED, however, says these are just parts of the galaxy. Something likely drew Arp 33 out into the integral shape. VV 6c and d seems a possibility. UGC 08596 shows a rather distorted arm on its east side and is also a possible cause of Arp 33's distorted shape.

NED and the Sloan survey identify a lot of other objects around Arp 33 that are similar to the VV objects. None of them are listed as being part of the galaxy, however. I've identified a few of them. It would get too crowded to identify them all. How some are part of the galaxy and the rest not I haven't figured out.

The image contains three asteroids. West to east (right to left), they are (102745) 1999 VZ111 at magnitude 18.2, 2006 ST289 at a very optimistic estimated magnitude of 19.8 and one not yet known to the Minor Planet Center. I did it yet again. Imaged an asteroid but discovered it a year too late to do anything about it so it is still undiscovered. It was taken April 7, 2010 and not processed until now. I do have to clean up this backlog somehow.

The 200" had sufficient field of view to do the entire group with its corrector lens in place. These online images are not made from the original plates but from first generation prints, Arp processed to bring out the detail he was interested in.

Arp's image of Arp 33
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp33.jpeg

Arp's image of the group Arp 326
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp326.jpeg

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

Related Designations for ARP033

ARP034

While this is a nice trio of galaxies Arp 34 is only NGC 4615 the big blue one as it is classed by Arp as: Spiral Galaxies, Integral sign. To me, none of his integral sign galaxies are all that close to the appearance of the sign. To me, this one looks more like an upside down double stinger scorpion. I think he was mainly interested in the long drawn out arms. In this case NGC 4615 is a starburst galaxy as indicated not only by its vivid blue color but also by its intense IR emission indicating there are far more stars being born in this galaxy but they are hidden behind their dusty cocoons which emit strongly in IR light as that's the only frequency that can escape the dust. Its official classification is Scd. The other two galaxies are NGC 4614 the odd barred spiral with two arms that seem to form a near perfect ring. Note that on the SW side a faint outer arm is visible. NED classes it as SB0. NGC 4613 is the smallest of the three and is classed as Sa by NED and a lenticular galaxy (S0) by a note at NED. Sa seems to better fit my image. All three are located about 230 million light-years away and do form a true group. which, if either, caused the distortions in NGC 4615 and threw it into starburst no one sees to know. Neither seems all that distorted as you'd expect after such an encounter. Maybe it was yet another galaxy out of my field. Arp 34 as well as the other two NGC galaxies in the image, 4613 and 4614, were discovered by Heinrich d,Arrest on May 9, 1864.

This note at NED about the three galaxy system is interesting:
"RSCG 64.-RSCG 64 is a very tight system (<20 kpc in radius) with a low velocity dispersion ({sigma}_RSCG_ = 111 +/- 74 km s^-1^). The system is near the edge of a small apparent void. Only five galaxies within the entire region are roughly coincident with the RSCG in velocity space, and the nearest of these is 560 h^-1^ kpc away from the RSCG center. RSCG 64 is probably an isolated, gravitationally bound system. No signs of tidal interaction are evident." So they can't find the cause of the starburst activity either.

Follow a line from NGC 4615 through NGC 4613 then on to an orange star a bit fainter than the one on top of NGC 4613. Go the distance between NGC 4613 and that orange star. That brings you to the center of a very distant galaxy cluster NSC J124121+260545 a bit over 3 billion light years distant. If I blow up that area I see a bunch of very faint galaxies and a few brighter ones in the area. The cluster itself though is hard to define. NED gives little information on it.

A bit west of NGC 4613 and north you come to a bright somewhat orange star. It is about in the center of another galaxy cluster, NSCS J124121+261031 at 4.5 billion light years. 28 galaxies are listed as being in the cluster. I see far more on either side of this star arranged in two clumps one to the east and one to the WSW of the star. But there are far more than 28 in either of the clumps.

The eastern clump is a quite long group heading east. Toward the far end of this large clump of galaxies is the location of yet another galaxy cluster, NSCS J124153+261101 at 2.6 billion light years. It has 18 members. Again I see too many. The galaxy counts may have been made from the POSS plates. I am going much deeper than they do so this may explain the excess.

I'm not done with galaxy clusters in the image! Follow the line from NGC 4615 through 4613 and on to the first bright blue star. That marks the area of yet another galaxy cluster that appears to be at the SW end of a band of galaxies and galaxy clusters. It is NSCS J124108+260838. It is listed as containing 41 members, more in line with what I see on my image, and is 4 billion light years distant.

The asteroid in the image is (46920) 1998 SX12 MAG 17.9 Color data was taken between to luminosity sessions so the trail is broken. It is near the top right of center and is aimed at a somewhat blue galaxy that also appears as a short streak.

All three galaxies were discovered by Heinrich d'Arrest on May 9, 1864.

Arp's image: http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp34.jpeg

14" LX200R @ f/10, L=6x10' RGB=3x10', STL-11000XM Paramount ME

Related Designations for ARP034

ARP035

Arp 35 is considered a pair of interacting galaxies even though they are widely separated. The two galaxies are LEDA 001434 in the center and LEDA 001431 well below it. They are in the constellation of Pisces. Both are about 210 million light-years from us. The later seems mostly unchanged by the encounter but 1434 certainly has been torn up by the near collision. Arp has a class for integral sign galaxies, none of which is the integral sign galaxy oddly enough. Like Arp 24 the companion isn't involved in his classification of the galaxy and isn't mentioned that I find. Still, some catalogs consider both to be part of Arp 35.

Arp's photo of this galaxy system is at:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp35.jpeg

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

Related Designations for ARP035

ARP036

Another twofer deal in Arp galaxies located in Canes Venatici, about 3 degrees northeast of M3. Arp 183 on the left is UGC 8560 and Arp 36 on the right is UGC 8548. Both are about 240 million light-years distant. Both appear highly distorted yet are cataloged very differently by Arp. This image was taken through some haze for 4 of the 6 luminosity frames so doesn't pick up the faint parts of the galaxy as well as I'd have liked. Another I should revisit but probably won't.

Arp 183 is in Arp's class of galaxies with narrow filaments. Apparently he is referring to the very faint spur above the apparently drawn out arm. At least that's what his comment probably refers to when he says: "3 faint patches constitute third arm or filament." The patches are better seen in his image. The two galaxies along the long drawn out arm of Arp 183 are SDSS J133451.48+312306.9 of unknown distance and 2MASX J13345139+3123014/SDSS J133451.36+312301.3 at 1.5 billion light-years. The latter is obviously not related to Arp 183. The former, if at the same distance as Arp 183 seems way too small to be involved. NED classes Arp 183 as an Sb spiral about 240 million light-years distant. The best candidate for what distorted Arp 183 is nearby Arp 36 which is also apparently distorted.

Arp 36 is, like Arp 183 about 240 million light-years distant. It is classed as SB? Arp put it in his Spiral Galaxies: Integral sign class. Though it makes a rather poor integral sign to me. His comment: "Knots in arms approach appearance of small companion." I would certainly agree with that comment. In fact, some catalogs do list the brightest knot in the eastern (left) arm as a separate object. Oddly, a note at NED under Arp 36 actually refers to Arp 183 when it says: "SB with a double companion at the end of the single developed arm." As shown above, at least one of these "companions" is a distant background galaxy. Another note, this one on Arp 36 asks the question "Two cores?" I don't think so. This other bright object seems, in my image, to be a blue knot of new massive stars at the end of the western bar where the arm starts. There's a similar dimmer one at the start of the eastern. Several others are visible as well. Such massive star formation is common in near galaxy collisions as may have happened here. Both galaxies certainly show this effect.

The tight trio of galaxies below Arp 36 consists of WAS 75 at about a half billion light-years and 2MASX J13341649+3117095 at about three-quarters billion light-years. The third galaxy is SDSS J133417.21+311718.0 distance unknown. Below is small S0 like spiral SDSS J133417.57+311645.5 also distance unknown. The two with unknown distances are labeled with a question mark. West of this group is a pair of very red objects. The bright one is 2MASX J13340124+3117057 at 1.5 billion light-years. The SDSS catalog lists the western one as a 20th magnitude star. Its PSF doesn't look like a star in my data. Looking at the SDSS image I tend to doubt the star label but that's what I've labeled it in the annotated image. It could be the halo of the galaxy is causing the confusion so I'll reluctantly defer to the SDSS.

Below the above galaxies is, the IR strong galaxy 2MASX J13341158+3114204 at 1.5 billion light-years. It is classed as S0. It's very unusual for an S0 galaxy to have the star formation in its core needed to reach the level of an IR galaxy. Also, it must be huge to appear so large at such a distance. A quick calculation assuming it is fully face on to us puts it at about 160 million light-years in long diameter. I can't recall an S0 galaxy that large. Sure would like a closer look at this one.

Near the left edge is the distorted galaxy SDSS J133539.83+312336.1 at 800 million light-years. It is partly hidden behind a bright star, unfortunately.

There's one asteroid in the image, (239730) 2009 BL170 at an estimated magnitude of 19.4. It is moving in pro-grade motion rather than retrograde as it was taken early in the morning. It also shows how conditions improved during the image. The first part of the trail (long part) is dimmer than the shorter later luminosity images. Dawn was breaking so I couldn't get any more and never went back. The gap is due to the taking of the color frames.

Arp's images:
Arp 36
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp36.jpeg

Arp 183
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp183.jpeg

14" LX200R @ f/10, L=6x10' RGB=2x10'x3, STL-11000XM, Paramount ME

Related Designations for ARP036

ARP037

Arp 37/M77 may be the most important entry in his catalog. Though not for the reason that he included it. Arp included it as the first entry under Spiral Galaxies with Companions on Arms: Low surface brightness companions. I can't even find the companion in Arp's image nor can I find anything in the literature on it.

Arp 37 is located in Cetus right on the celestial equator and is about 30 to 60 millions of light years distant. Even the Hubble images can't decide on a distance with one article in 1990 http://hubblesite.org/news_release/news/1990-13 saying 30 million light years and another in 1994 saying 60 million http://hubblesite.org/news_release/news/1994-07 while NED gives estimates of 33 to 47 million light years using Tully-Fisher measurements. Redshift isn't very reliable this close but does show 42 million light years. So spin the dial and pick a distance. Most sources say it is close to NGC 1055 in my previous post. But the distance to it is also all over the board but 60 million light years seems to be gaining popularity for it. For now, I'll go with that for Arp 37 as well.

While Arp says it has a low surface brightness companion on its arm I see at least 4 that could fit that description, All outside his image so can't be what he is seeing. The two with redshift distances are over a billion light years further away so meaningless to Arp 37's evolution.

In any case, this is unimportant. The galaxy is important for a far different reason. It is the archetypal example of a Seyfert galaxy. Quasars far outshine the galaxy they are in. Seyferts seem to have a similarly active core but one that isn't anywhere near as bright. They can be divided into two camps. Those with very broad emission lines indicating super high velocities for the gasses emitting this light and those with narrower lines indicating very high velocities, just not as high as the first group. The first is called Seyfert 1 and the second Seyfert 2. M77 is a Seyfert 2. But then things get complicated.

At one time it was thought the difference was age as quasars are seen mostly at distances of over 2 billion light-years with Seyfert 1 seen, on average, somewhat closer and Seyfert 2 galaxies tending to be closer yet. Since distance indicates age we are seeing quasars at a younger age of the universe than Seyfert 1 galaxies tend to reside with Seyfert 2 galaxies tending to be seen only in the more current universe. So is this due to the black hole that powers each having used up its easy fuel so not being as energetic as in the past? That has been the prevailing idea for some time now but studies of Arp 37 (M77) are causing some doubt.

Lately, this idea is falling somewhat out of favor though likely contains some truth. Study of M77 which Hubble and radio telescope arrays can see in fine detail is showing that we tend to see quasars fully face on to the jet emitted by the black hole. They are super bright since we are looking down their gun barrel. This greatly increases its brightness to where it overpowers the galaxy itself. Alignment is critical for this. We see them mostly in the early universe because we see a much higher volume of space and thus by the law of averages see more of them since there are more to see. Seyfert galaxies are just as common as today, just they are too faint to see at that distance because their light is blocked by the inner disk of the galaxy that surrounds the black hole. Only when they are close enough for the galaxy itself to be seen do we recognize their true nature.

Seyfert 1 galaxies have the jet tilted away from us so we don't see it directly but do see what they illuminate. Since we are seeing to near the core we see the high velocities involved. Seen at more of an angle these are hidden by the disk and we see only illuminated clouds further from the black hole and thus clouds with lower velocity. These are dimmer yet so must be closer, on average, for us to see and recognize them. We now can measure the angle of such disks and find those of the few Seyfert 1 galaxies we can measure aren't tilted as much as those of Seyfert 2 galaxies. So it is possible Quasars and Seyfert galaxies are really the same type of object, just that our view is more blocked in the case of Seyfert 1 and 2 galaxies by the inner core of the galaxy itself.

M77 is important here because while its basic spectrum screams Seyfert 2; by using techniques to peer into the hidden regions it shows a Seyfert 1 spectrum. It is both! Just that the Seyfert 1 characteristics are hidden behind the inner ring. Both are seen in a cone illuminated by its black hole. Some papers describe it as an overt Seyfert 2 and a hidden or closet Seyfert 1. NED recognizes this by classifying it as (R)SA(rs)b;Sy1 Sy2.

Both theories may carry some truth. Maybe the James Webb space telescope will further illuminate this situation (sorry, I couldn't resist).

I found more articles on this galaxy than any Arp galaxy I've researched. Far too many to even start to read. There must be over 1000 though I didn't try to count them. With that many, there must be at least one for every possible theory about this galaxy. So while this is my longest post, I had far more information available I could sort of understand. But I'm not done yet.

Besides the Seyfert angle, Arp 37 has a very large outer disk of faint stars. These are likely due to an interaction with another galaxy.

More on M77 can be found at http://www.seds.org/messier/m/m077.html which was discovered by Pierre Méchain on October 29, 1780 then verified and recorded by Charles Messier on December 17, 1780.

One aspect of my image bothered me when comparing mine to others. I see a faint blue halo about the main spiral. It is a bit brighter on the western side. I couldn't fathom any reason my processing could have done this. Then I came across this article about an ultraviolet halo in the galaxy. Its position seems to match my feature. Since my filters block UV light this makes no sense unless the halo is also seen in blue light. Probably not related but it does make me wonder.
http://apod.nasa.gov/apod/ap960910.html . The orientation of the linked image is the same as mine making the similarity easy to spot.

My image seems to fit the above description of quasar vs Seyfert perfectly as it contains many quasars and some Seyfert galaxies as well as two that seem to have characteristics of both. One more quasar-like (identified as Q/G? on the annotated image) and one more Seyfert like (G/Q?). Quasars range out to over 10 billion light years with a Seyfert 2 galaxy [G(SY2)] at 4.4 billion light years and several clusters over 3 billion light years distant. One cluster I've marked is behind Arp 37's outer arms and invisible in my image. I mark its center only because it is almost on top of one of the larger galaxies seen the disk, the only one without redshift value unless it is a member of the cluster. Unlikely, but they vary by only a few seconds of arc so thought it worth pointing out. Another cluster at about the same distance is also positioned behind the disk at the 2:30 position. I didn't mark it. All clusters marked are said to be 2 to 3 minutes in diameter. I've drawn a line to their approximate center. NED only gives their approximate position to an accuracy of +/- about 6 pixels.

There are two asteroids in the image, one of which isn't in the minor planet database. I've identified it as unknown. Several other similar streaks are seen in the outer disk of the galaxy, all are seen in their entirety in each subframe so aren't asteroids. The unknown, however, shows as a very slightly elongated object in each subframe so is a real moving object. Several have asked me why I don't take just one 40 minute frame. This is one of several reasons. It allows me to separate real asteroid trails from noise created impostors.

Arp's image:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp37.jpeg

Sloan image:
http://astronomerica.awardspace.com/SDSS-9/M77.php

14" LX200R @ f/10, L=4x10' RGB=3x10'x3, STL-11000XM, Paramount ME

Related Designations for ARP037

ARP038

Arp 38 is a photogenic face on spiral in Draco about 60 million light-years distant. Arp put it in his class for spirals with low surface brightness companions on the arm. One major problem here. The companion probably doesn't exist. NED shows no other galaxy in the area. It appears the "companion" is most likely just star knots to the northern side of the galaxy. Arp's comment reads: "Small ring in arm on north side, part of large ring on following side shows in H-alpha only." This would be the position of the star knots. Kanipe and Webb make no mention of the companion in their book. They just repeat Arp's comment.

The only other mention of a companion that I found is in a paper by B. A. Vorontsov-Velyaminov from 1975 titled "Atlas of Interacting Galaxies, Part II and the Concept of Fragmentation of Galaxies. This is the VV catalog in which Arp 38 is entry 444. There they say: "One of the rare cases where the companion at the end of a spiral arm is also a spiral. Here, a chain of H II regions encircles the massive condensation thus forming a small spiral ripening at the periphery of the larger one and liable to gemmate." Again this reads more like a feature of the galaxy rather than a separate one except for the part where they state it really is a spiral. But do they mean a spiral form rather than a galaxy?

Arp 38 does have some plumes to the north that likely indicate some interaction in the past. I suppose the bright knot to the north could be mistaken for a galaxy. A very basic combine of a couple filters is seen at http://cseligman.com/text/atlas/ngc6412hst.jpg There the "companion" appears to be just a very large HII region and star cluster. I suppose if it ate a dwarf galaxy with lots of HII regions this might be the some of the remains. This could explain the plumes as well.

There seems some disagreement about how to classify this spiral. NED says SA(s)c while the NGC project says SBc making it a barred spiral. It sort of looks barred in my image at first glance. But looking closer in the enlarged image what appears to be a bar to the north is really star knots at the start of a spiral arm that comes out of a circular core region. There is no sign of a bar like structure to the south. This is even more evident (of course) in the Hubble Space Telescope image above. It was discovered by William Herschel on December 12, 1797 but isn't in either of the Herschel 400 observing programs.

The image is out of the area of the Sloan survey so there is little data on the field. While NED lists a couple dozen galaxies in the field none have much data and nothing about distance. No annotated image was prepared due to this lack of data.

Arp's image: http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp38.jpeg

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

Related Designations for ARP038

ARP040

Arp 40/IC 4271 is another from Arp's category for spiral galaxies with low surface brightness companions on their arms. It is located in Canes Venatici about 760 to 770 million light-years distant. I suppose the southern member is the "companion" but to me, they are of about equal surface brightness, neither being all that faint. I certainly don't see either as being on an arm of the other. To me, it appears the southern galaxy is in the foreground. It has a dusty disk larger than the optical disk. It is easily seen against the more distant northern galaxy as a dark band "separating" the two galaxies. It is seen in Arp's and Sloan images as well.

Are they interacting? Hard to say. Both are Seyfert 2 galaxies. At one time this was thought to be a pretty good sign that interaction was going on. Though now it appears such classification doesn't necessarily mean an interaction. Though with both being Seyfert 2 it might in this case. Still, I see no real sign of distortion to either (unless that dust disk qualifies). Other than these two overlapping I really don't see what Arp saw in this pair.

Stephane Javelle discovered IC 4271 on July 10, 1896. Did he see both as one, only the larger or both separated? Dreyer said of Javelle's discovery; "faint, small, round, gradually brighter middle, mottled but not resolved." The round comment would seem to indicate he saw only the top one but by my measurements, both are about equal in surface brightness so he should have seen both. Most catalogs consider IC 4271 to be both.

Far more interesting to me is a pair I had on my "Arp-like" list. I've managed two, and sometimes more Arp galaxies in one image but this is the first (time I also have one from the Arp-like list in the image. It is in the lower left corner and I didn't realize it was in the shot at the time. If I had I'd have framed the shot better. It is SDSS J132957.37+371744.8, a spiral galaxy at a distance of about 750 million light-years. It has a very weird structure. A wide arm that appears to have been drawn out with no corresponding arm on the other side. More interesting though is that from the bottom of the galaxy a faint "arm" comes out of nowhere and appears to lead west and a bit north to a faint galaxy, SDSS J132953.47+371750.6. Another galaxy appears connected to it a few seconds of arc to the northwest. That one is not listed in the Sloan survey or in NED. Is this a real connection? I see hints of it in the Sloan image and it appears quite real in my data. Note too how the big spiral seems to have a piece cut right off its north side! Sloan survey lists the western side of the galaxy as a separate entry, SDSS J132956.73+371747.9 with no distance noted. Could it really be a separate galaxy? The odd arm seems to come from its position, wind around and behind the main galaxy then come out the other side as the wide arm, almost as if it were a huge plume of a disintegrating galaxy. This could explain the cut off appearance. Or is my mind wandering afield at 2 a.m.? The main galaxy is also in the 2MASS IR catalog as 2MASX J13295738+3717447. So is the galaxy directly east, 2MASX J13300048+3717277 with a redshift distance of 760 million light-years. Could all three of these plus the 2 Arp 40 galaxies all be part of the same group? Probably. Just above the top of my image just a hair left of center is the center of the Abell 1749 galaxy cluster with a diameter of 40' of arc containing some 51 galaxies. Its distance is listed as 770 million light-years.

The galaxy north of Arp 40 is 2MASX J13295621+3718226, distance unknown. Toward the lower left corner is the galaxy pair (GP), NGP9 F270-0262533/PGC 2097470 at 1.9 billion light-years. This doesn't mean they are interacting but they could be. At that distance, my resolution is insufficient to say either way.

These galaxies may be too far away to be photogenic but they sure are interesting, just the same. My enlarged, cropped image includes both galaxy systems at 0.67" per pixel.

Arp's under exposed image
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp40.jpeg

14" LX200R @ f/10, L=6x10' RGB=2x10'x3, STL-11000XM, Paramount ME

Related Designations for ARP040

ARP041

Arp 41/NGC 1232 belongs to Arp's class for spiral galaxies with low surface brightness companions on their arms. It is located in Eridanus some 67 million light-years distant by redshift. At -20 degrees it is too low in my sky for me to get a decent image. I normally don't even try when this low but this one was big and bright so had to try anyway. I'm glad I did. While fuzzy I still was able to pull out some of its many HII regions even though no H alpha filter was used. The galaxy was discovered by William Herschel on October 20, 1784 but isn't in either of the Herschel 400 programs.

While Arp apparently considered the companion to be on the arm that is likely not the case. Optical redshift puts the companion, NGC 1232A, nearly 5 times more distant at 293 million light-years. But a note at NED says that HI radio data shows a redshift of about the same as Arp 41 itself. They offer no explanation and call it a mystery. Considering it is on an arm I would think the radio HI data is for NGC 1232 in the background rather than NGC 1232A. I saw nothing to rule this out which puzzles me. NED makes no mention of this difference. Older papers also consider it a dwarf companion saying things like; "Typical dwarf SB(s)m system." and "Dwarf SB(s)m satellite at 4.0 arcmin following NGC 1232."

NED classes NGC 1232 as SAB(rs)c with HII so sees both elements of a normal and of a barred spiral. The NGC project says SC I. The companion is classed by NED as SB(s)m same as the papers seeing it as a dwarf companion. If it is really 5 times more distant then it is not a dwarf. Hubble would resolve stars in it at the distance of NGC 1232 but unfortunately has not looked at it. For now, I'm going with the visual redshift distance of about 300 million light years.

This is a region of the sky with little research. I found little at all on the field so haven't prepared an annotated image.

Arp's image: http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp41.jpeg

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

Related Designations for ARP041