ARP328

Another Arp pairing

Arp 328/Hickson 72/UGC 09532. This is a chain of galaxies located in Bootes. All but one of the galaxies are about 600 million light-years distant, the other nearly twice as distant and thus not a member. Before going further and looking only at the full or cropped image, see if you can determine which is the odd galaxy out. It may not be the one you think. Arp put this group his class for galaxy chains and had this comment: "6 galaxies more or less in line; center one has semi-stellar companion." There are 7 in the chain including the sneaky interloper. Hickson also includes only 6 but one he includes is the "fraud". NED shows 7 galaxies for Arp 328 while Arp himself limits it to 6 as does Hickson. Both leave out the most southern. Yet one note at NED reads: "With respect to the original Hickson list we have included the amorphous object g which clearly interacts with galaxy c. This is the one I've marked as VV164g. G is blue and does seem to have a bulge toward c but I'm not sure this is sufficient for it to be clearly interacting. This brings us to the "semi-stellar companion" I assume he is speaking of D. While in my image it may appear to have two cores of about the same brightness the SDSS image clearly shows the southern one to be a star. There is a slight brightening north of the core, best seen in the Sloan image but it isn't semi-stellar. Nor can I see much of anything in the burned-out core of Arp's image as it is on the website. But E does show what appears to be a distant galaxy through its disk on the east side. Could this be what Arp refers to? It does show in his image. If the possible 7th galaxy is included then E would be in the center. I've found nothing to decide this issue.

Below and left of component g is yet another compact golden elliptical like galaxy, SDSS J144759.73+190202.0 at 18th magnitude. No one considers it part of the group. Nor is any redshift data available for it. There are several small galaxies about component A as well. Are they satellites of A or distant line of sight galaxies? Probably the latter though a note at NED considers this possible.

A is classed as S0, B as S0?, C as E2, D as SB0, E as Scd, F as S0 and G as S0?.
___________________________

Arp 47/MCG +03-38-014 is classed by Arp under Spirals with low surface brightness companions on arms. I suppose that refers to the little galaxy off the north arm that curves back sharply. That galaxy is 20th magnitude SDSS J144715.24+185134.8. No redshift is given so it's unknown if it is truly a companion. There is the very obvious galaxy to the west of MCG +03-38-014. It is 16.6 magnitude NPM1G +19.0402. NED and other catalogs consider these two a pair. In fact, NED lists these to under Arp 47. Seems way too bright to be the companion on the arm Arp refers to. So which is it? I still think it the one that definitely appears to be on the arm and certainly is faint. Unfortunately, NPM1G +19.0402 doesn't have a redshift value either which doesn't help us any. NED makes no attempt to classify this obvious spiral or either "companion".

Arp's image is one of his poorest. This isn't Arp's normal work. Makes me wonder if some night assistant took this data rather than Arp himself. He may have had quirky ideas bordering on crackpot in later years but his telescope work was very precise. One possibility is Arp did, like I did, and took both of these with one image. This would have pushed the Winn Corrector to its limits and maybe beyond. Arp 48 may have been right at the edge of the image where the Winn Corrector couldn't quite handle the prime focus distortions. The stars radiate away from the position of Arp 328 like it was centered and this one just too far away for full correction. The elongation of the star in the lower right corner seems greater which fits this idea. I can't see Arp guiding this poorly.

There's no redshift data on anything in the field other than these two objects. NED lists several thousand galaxies in my field but except for these two Arp's, there's nothing on it. Note however that both are at the same approximate redshift distance and thus quite likely part of the same group.

Arp's image of 328
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp328.jpeg

Arp's image of 47
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp47.jpeg

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

Related Designations for ARP328

ARP329

Arp 329 aka Hickson 55 is yet another chain of elliptical galaxies Arp logically put in his Group Character: Chains of galaxies class. Also known as UGC 6514 1 through 5. This is a rather puzzling chain. 4 of the galaxies show a redshift that puts them at about 700 million light-years with only a very small variation, smaller than normally found in such chains in fact. But then there's that oddball one. Can you spot it?

Most catalogs list these under one number with either a letter A-E or number 1-5 designating which is which. Since these are assigned in RA order it is kind of confusing. Only the PGC catalog gives them separate numbers but again in RA order. Top (north) to bottom they are PGC 035574, PGC 035576, PGC 035575, PGC 035573 and PGC 035572.

The odd galaxy out is the second from the top, PGC 035576. It is the smallest and bluest of the bunch. Its redshift puts it a bit more than twice as distant as the other four at about 1.5 billion light-years. No wonder I picked up so little detail. So is it just a line of sight coincidence or is it really much closer. Arp would likely argue for the latter while most other astronomers the former. To me, its different color and its smaller size would cause me to vote with the coincidence theory. Oddly, Arp seems to have no comment on this one. Though he does state in general that he considered such a coincidence to be a 1 in 10^4 to 1 in 10^6 chance level. I don't understand how he came up with this, however. Sounds to me to be calculating the chance in a particular group for such a coincidence rather than the chance that some groups will have such a coincidence. I know I have at least one math prof on the list, maybe he has some ideas on this. Arp also considered chains even without an oddball to be highly unlikely due to chance. Now we know that in small groups gravity will tend to cause them to fall into such chains. Also, remember we are seeing this in 2D, we really can't say much about the depth involved. Though the math now says real chains should be about as common as we find them to be.

Very few of the galaxies in the image are in any catalog except the MAC which gives little useful information. I find redshift data mostly missing except for the Hickson group and one other.

The elliptical above and right of Arp 329 is 2MASX J11314875+7054045. While it is the same color and about the same size and brightness of the biggest member of the Arp group, without redshift data I can't tell if it is a member or not. The blue spiral to the east (left) of Arp 329 is MCG +12-11-033 at magnitude 17. The blue galaxy near the bottom edge a bit left of Arp 329 is CGCG 334-036. East (left) of this galaxy is the tiny S0 galaxy 2MASX J11340329+7035372 at about 125 million light-years (much closer than Arp 329). The spiral to its upper left is 2MASX J11344815+7039213. It appears there's a distant group of galaxies behind it but I find nothing on them other than a couple are also IR galaxies with no redshift data. The glue blob of a galaxy west of the last galaxy and above the previous one is PGC 2737488 at 18th magnitude. I could find no entry for the blue galaxy above and a bit left of Arp 329. I didn't check the MAC, however.

The elongated, very bright, yellow star near the left edge is Struve 1551, a double star the brighter is G5 and thus nearly white since I balance to G2 being white. Its companion appears somewhat yellower. They are separated by about 7" and thus overlap due to the heavy stretch applied to the image.

Arp's image
http://nedwww.ipac.caltech.edu/level5/Arp/Figures/big_arp329.jpeg

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

Related Designations for ARP329

ARP330

I'd been hoping for a really good night to image this group. Finally, we had one and the northern lights turned on so bright you could read a newspaper. I might as well have been imaging from downtown Chicago. I ended up throwing out a third of the luminosity images and half of the red, green and blue images keeping the best two. Still, I had super nasty gradients. Normally my background would be about 250 counts out of 65,000 but this image was 14,000 at the upper left, falling to 8,000 near the lower right but then a huge ray or something popped up taking the very lower right corner to 39,000! Thank goodness for GradientXTerminator. It took several applications using various techniques but I ended up with a usable but not great image. My biggest worry is color balance after removing so many gradients. But I think I'm rather close to being correct even though most of the galaxies seem overly reddened.

Arp 330 is in Arps class: Group Character: Chains of galaxies. One note describes the group: "In a beautiful interconnected chain of six red compacts [faintest m(pg) = 18.5] and one blue crescent-shaped post-eruptive compact: m(pg) = 16.5.

From North to south the 7 galaxies are:
2MASX J16491727+5327127, no classification or red shift data, mag 17
2MASX J16491727+5327127, E0, 350 million light-years, magnitude 17
2MASX J16491130+5325573, E2 pec, 410 million light-years, magnitude 17
2MASX J16491152+5325113, E1, 410 million light-years , magnitude 15.6
2MASX J16491274+5324183, SBbc pec HII, 364 million light years, mag 16
MCG +09-27-093 mag 19
2MASX J16490837+5323334, E2 pec, 400 million light-years, magnitude 16
2MASX J16490401+5322254 no data

OK, that's 8. I included the last one as I'm not sure if it or MCG +09-27-093 is the 7th galaxy. 2MASX J16490401+5322254 shows well in Arp's photo and is a bright IR galaxy while MCG +09-27-093 is nicely tucked between two obvious members but barely shows in Arp's photo. So which is the 7th member most sources speak of?

The very red, large, barred spiral galaxy to the upper left corner is 2MASX J16501529+5333072, so yet another IR galaxy. It is apparently part of the same group at 400 million light-years. Its red color seems to fit the group as well. But it must be a much larger galaxy.

Within the main group is the lone highly distorted spiral. It isn't red at all. In fact, it has a rather large blue tidal area between the two larger elliptical's halos. The blue area is faint but seems real. Thus it must be interacting with the others and its redshift a poor indicator of distance.

The only other galaxy with a redshift in the image is 2MASX J16471357+5333403 in the upper right corner. It fits right in with the others with a redshift distance of 380 million light-years.

Going NW of Arp 330 about 7 minutes you come to the center of the Zwicky galaxy cluster ZwCl 1647.6+5337 NED shows it as having 157 members in a diameter of nearly 2 degrees, far larger than my image. It shows a redshift distance of -- you guessed it -- 400 million light-years. It appears nearly all its members are very red.

I've identified many of the galaxies around Arp 330 on a separate image. You might wonder about the galaxy at the top near a bright star. It wasn't in NED or SIMBAD. The Sky identifies it as PGC 281743 at magnitude 16.5. Apparently, it is not an IR galaxy so was missed by the 2 micron survey that picked up most of the galaxies in the image. What about the SHK galaxies? SHK stands for Shakhbazian Compact Groups. Number 16 on the list includes Arp 330 and surrounding galaxies. Most of the 2MASX galaxies are also members of the SHK 16 group. Those that are members of SHK 16 but not 2MASX cataloged galaxies I identified by their SHK 16 number. Arp 330 carries several other group designations such as CGPG 1648.0+5331 and I Zw 167. Like the SHK group, these may contain more galaxies than Arp did, I didn't check this, however.

Arp's image of Arp 330 is at: http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp330.jpeg

Even with the problems of the aurora my image goes deeper than his which surprised me.

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

Related Designations for ARP330

ARP331

The Pisces Cloud is 29 galaxies in Pisces galaxy cluster though common usage seems to refer just to the C2 group which is Arp 331. How many galaxies Arp considered part of his chain seems to vary with the source. Most say the 8 listed below excluding 373, 375 and 388 but others say 12 or more. It just depends on when you stop counting and how far east or west of the bright vertical chain you venture. If those I list Seligman leaves out 373 saying it is too far west.

Hubble classed this group as "Group Character: Chains of galaxies". It is also known as Zwicky cluster 0107.5+3212. The chain is too large for the FOV of the 200" so the photo Arp uses comes from 48" Schmidt camera. It appears to be a very short exposure as it only picks up the cores of the galaxies making them look a lot further apart than they do in my image. Arp's comment: "Symmetry around large central galaxy." This may be a clue as to which galaxies he considered part of his object.

Galaxies north to south with discoverer and date of discovery. Galaxies north to south with discoverer and date of discovery. Independent redshift is noted by ind. RS indicates a redshift distance. Both are in millions of light-years.


NGC 379 S0 208 ind, 241 RS William Herschel September 12, 1784
NGC 380 E2 208 ind, 189 RS William Herschel September 12, 1784
NGC 383 SA0 LERG* 208, 220 RS William Herschel September 12, 1784
NGC 382 E, 234 ind, 226 RS Bindon Stoney November 4, 1850
NGC 387 (east of 382) no class no ind 202 RS Lawrence Parsons December 10, 1873
NGC 386 E3, no ind, 240 RS Bindon Stoney November 4, 1850
NGC 375 E2, no ind, 254 RS Lawrence Parsons December 1, 1874
NGC 385 SA0, 208 ind, 214 RS Bindon Stoney November 4, 1850
NGC 388 east of 385 E3, no ind, 235 RS Bindon Stoney November 4, 1850
NGC 373 E, no ind, 238 RS John Dreyer December 12, 1876
NGC 384 E3, no ind, 180 RS Bindon Stoney November 4, 1850

All carry this NED note:
Faint compact member of the Group C2 of elliptical galaxies forming one of the four prominent condensations.

So what about that lone spiral above NGC 375 (UGC 679). Include it and you get an even dozen that some writers say is the count. Oddly the MCG catalog lists it as being NGC 375! Is it a member of the group though not mentioned by Arp? Looks like it may be. NED says it's likely about 214 million light-years away, only about 6 million more than the rest, and redshift puts it at 220 million light-years which is in close agreement as well.

The image is full of orange "stars" that are really galaxies. For instance just off the east end of the blue spiral are two of these star-like galaxies. One is slightly above and left, it is very orange. A bit closer and below is a yellow-white "star" that is also a spherical galaxy. I have no redshift or other distance indicator but suspect they are part of the same group, just smaller members.

I had to move the field further north than I wanted due to the 6th magnitude star. When I centered everything it was out of the field but sending in some nasty ghosts. The only way to get rid of the worst of them was to move it into the FOV. For some reason, my filters scatter more green and blue than red light so even though it is a K0 star it has a rather cyan halo from the excess green and blue. I didn't try to fix this.

Many galaxies in the image I didn't mention had redshift data. All of which indicate they are members of this group. Far more either had no redshift data or weren't in any catalog. This area hasn't been covered by SDSS.

NGC 390 is just one of two stars I've listed as a double star in the annotated image. Guillaume Bigourdan saw it on November 19, 1884 recording it as "very faint, very small, stellar. Unfortunately, while these two stars are nearby his position fits neither well enough to tell which he was seeing. Most likely the upper one so that's where I put the label. It itself is a double star which might have made it appear slightly fuzzy. Some say PGC 4021 further east and a bit north is what he saw. That, though, just stretches the NGC position too much. Certainly doesn't fit his stellar description either.

Arp's image with the 48" Schmidt telescope:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp331.jpeg

*LERG stands for Low Excitation Radio Galaxy

14" LS200R @ f/10, L=5x10' RGB=2x10'x3, STL-11000XM, Paramount

Related Designations for ARP331

ARP333

ARP 333/NGC 1024 lies in Ursa Major near the bear's nose. It is classed as (R')SA(r)ab and is about 150 million light years distant. Arp thought it peculiar enough for his catalog due to its extremely thin arms but had no category for this so put it in his Miscellaneous category. ARP 337 (M82) being the most famous member of this class. His comment on Arp 333 reads "Thin circular arms, star in southeast superimposed on wisp."

Inside the faint disk of the galaxy are two short blue arm segments that are extremely thin. I don't know if he is referring to them or the outer edge of the disk. The star at the southeast end that obscures the "wisp" is a pain. While only the wisp is obvious in his image, mine shows quite a bit more in this area. Is it the remains of a partly cannibalized dwarf? I find nothing on it. If you compare my image to Arp's at this star you will note a small reddish condensation just above the star in my image that is missing from Arp's image. This bothered me at first. Then I checked the DSS 2 red and blue plates. Arp used film very similar (grainier) that was used for the DSS images using a blue sensitive emulsion but imaging through a yellow filter much of the time. This tended to neutralize the color to better match a true spectral image for visual light. But it does eliminate red objects. Sure enough, the object is missing on the blue plate and present on the red. So its absence from Arp's image is easily explained by his emulsion choice. So much for my "supernova" discovery. NGC 1024 was discovered by William Herschel on September 18, 1786 but isn't in either H400 observing program.

Unfortunately, this one is outside the SDSS coverage so there's not much information on this area. With the two galaxies to its east, it forms a three galaxy group; WBL 082/KTG 09. The little northern spiral is NGC 1028 classes Sa by NED and SB at the NGC Project. It looks barred to me so I doubt the Sa classification. Its arm structure is very odd and non-symmetrical. To me, it is more deserving of an entry in Arp's atlas than NGC 1024. The redshift distance of 380 million light-years is quite at odds to its non-redshift estimate of 250 million light-years. The lower is NGC 1029 classed as S0/a by both NED and the NGC Project. Both were discovered by Albert Marth on October 1, 1864.

Now while these three are considered a group NGC 1028 is small because it over twice as far away as the other two at 380 million light-years. Thus it is only a line of sight group member. It looks like it could have been included in Arp's One Heavy Arm category.

While there are other sizable galaxies in the image I find redshift data on only two others. One is the edge on the spiral southwest of Arp 333. It is FGC 0326 (Flat Galaxy Catalog) classed as Sd and is about 350 million light years distant. So another background galaxy as its angular size would indicate. The other is southwest of NGC 1029 and southeast of Arp 333 on a line through the major axis of Arp 333. It is a small (in angular size) reddish spiral. Like all the other identified galaxies in the image but without distance data it is from the 2MASS survey, 2MASX J02392466+1045321. It lies twice as distance yet again at about 750 million light years. I find no classification on it. There appears to be another "flat" galaxy just west of NGC 1029. I couldn't find it listed at NED though the very red starlike galaxy between it and NGC 1029 was listed as 2MASX J02393145+1047331.

Arp's image with the 200" Hale Telescope
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp333.jpeg

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

Related Designations for ARP333

ARP334

ARP 334 is located in the constellation of Canes Venatici at about 340 million light-years. Arp put it in his Miscellaneous class. His note gives no mention of why he thought it worthy of his atlas. His note simply notes that the second star to the south is not quite stellar. That's even more obvious in my image. Arp 334 is otherwise known as UGC 8498 and is classed as Sb at NED. It has some faint tidal spray and an apparent hole in its disk in the area of the southern galaxy. Are the two related? Wish I knew. The nearly stellar galaxy is SDSS J133025.68+313617.6. But the survey didn't take any redshift data on it so no way to know its approximate distance. Something apparently disturbed Arp 334 and it is as good a candidate for the mugging as any in the area.

There are several small galaxy clusters in the image and one huge one. The huge one is Abell 1752 which is labeled at the top left of my image. The label marks the center. It is listed as having a diameter of 52 minutes so would cover much of my image. No galaxy count or distance is given. The most obvious galaxy cluster in the image is GHO 1328+3157 a cluster of 24 galaxies with a distance of 2.6 billion light-years. I've marked its center as GC followed by its distance. Note the center seems a bit southwest of the core region and the anchor galaxy. The Kanipe-Webb book on the Arp Atlas considers this group part of Abell 1752.

The galaxy that appears to be in the densest part of the GHO 1328+3157 galaxy cluster is 2MASX J13302928+3141354. It is listed as a Bright Cluster Galaxy rather than cD. Also, its redshift seems to put it somewhat further away than the listed distance to the cluster. NED shows a redshift that puts it 3.1 billion light years distant, about a half billion further than the cluster estimate. That seems a large discrepancy. Maybe the estimated cluster distance has a problem. The galaxy is the reddest I can recall imaging.

To the southwest of Arp 334 is the galaxy cluster candidate, NSC J133008+313012 at 2.4 billion light years. No size is given. It has the label GCC marking its center position.

Another candidate cluster, this time at 2.6 billion light years is located north and a bit east of Arp 334. Again, the label GCC marks its center coordinates.

Yet another galaxy cluster is shown at NED due west of Arp 334. It is NSCS J132936+313646 and has no distance, size or diameter given. There appears to be a small tight group of galaxies just east of the position. I'd cover up the galaxies if the label were centered on the center so it is immediately west of the label in this case which reads simply "GC ?" due to no distance being given.

On the eastern edge of my image just below center is a galaxy and galaxy cluster with the same coordinates. The cluster is MaxBCG J202.95428+31.57728 and is listed at 2.6 billion light-years while the "Bright Cluster Galaxy" is 2MASX J13314900+3134377 at 2.5 billion light-years. That position is marked with "G/GC" for the label.

While looking up information for my annotated image I again came across a galaxy, not in NED. It is southwest of Arp 334 and is marked by a "?" Just above it is a fainter galaxy. That one is SDSS J133006.12+312859.0 with no distance given. The third object is a star. So why is the fainter galaxy included but not the brighter? I keep running across these. Many more probably exist in the image, just that this one happened to interest me so looked it up specifically and found it wasn't there. I suppose with the millions of SDSS galaxies cataloged it isn't surprising a few get lost.

Arp's image with south up is at:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp334.jpeg

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

Related Designations for ARP334

ARP335

ARP 335 (NGC 3509) is a possible double galaxy that Arp put in his Miscellaneous category, M82 being the well-known galaxy in this classification. Looks to me it would have fit in his one heavy arm class. Ned and some other sources consider it a double galaxy. I thought maybe the other galaxy was the reddened blob directly north of the obvious nucleus. But its position isn't recorded as a separate galaxy in NED that I could find. Turns out that on the inside edge of the heavy arm there's a blue blob I considered a star cloud in the arm but most sources list it as a "galaxy within the bounds of NGC 3509." Whatever it is, I marked it in the ID image with its distance of 0.37 billion light-years, same as Arp 335. What about the two I have marked as KPG 265A and B? Well, it seems the Kanipe-Webb book on the Arp galaxies notes them in their book. NED says of 265B that it is the southern component of the double galaxy. But NED lists no northern component unless they consider that the main galaxy. NED says most of the parts it lists inside the galaxy are just parts of the same galaxy. Apparently, that included KPG265A. I've marked its NED position. Problem is the Kanipe Webb book shows KPG265A where NED has KPG265B and shows the orange blob I've marked with a question mark as KPG265B. So who is right? I have no idea. Maybe it is three galaxies. The obvious core defining one, 265B defining one that streams west from the bright knots and a third whose core is the orange blob and streams east creating the huge arm? Guess this is why Arp put it in his miscellaneous category. His only comment is: "Large luminous system."

NED classifies Arp 335 as SA9(s)bc pec. As mentioned it is about 370 million light-years distant. To appear so large at that distance it must be a huge galaxy and it is. I measure it as being 250,000 light-years across even without a southwestern arm like the northeastern arm.

Arp 335 is located in southern Leo. The image was taken in late January. Since I was making an annotated image to mark the various parts of Arp 335 I went on to list all galaxies NED had redshift data on as well as the position of several galaxy clusters.

In doing this I found two very blue galaxies (marked with ?) that the Sloan survey, as well as all others, seem to have overlooked. At least I found them in no catalog, I didn't check the Mitchell Anonymous Catalog however as it doesn't have any useful data. I've found similar uncatalogued blue galaxies in fields covered in detail by Sloan. There has to be some selection effect here but I don't know what it is. Since this was first written the SDSS has included these two, possibly due to my request about them. The western one is now listed as SDSS J110406.4+044955.5 at about the same redshift as Arp 334 making it about 36,000 light-years long. The eastern one is SDSS J110508.53+044919.8 and a bit closer at 320 million light-years and 34,000 light-years across.

The galaxy clusters are marked with GC. Some have lines that show the exact center as defined by NED. In other cases, the center is the center of the label itself. I only used the line when that would have covered up objects that might be of interest. You'll note that there's nothing there in every case but one. At the top left a cluster at 3 billion light-years has the exact same coordinates as a galaxy at 2.9 billion light-years. It may be the anchor of the cluster. The only cluster that I may see members of is the one to the upper right of Arp 335 listed as being 4.4 billion light-years away. While there's nothing at that exact position there is a bunch of faint distant galaxies below that position. Not marked is a Zwicky cluster listed as being the size of my image located at the right center edge of my image and containing 120 members. It is so vague I have no idea what it includes but it covers half of my image at least.

Note that there are a few galaxies at 0.91 billion light-years, another group at 0.37 that extends off my frame both north and south, There's a triad of galaxies at 1.7 billion light-years near the right edge.

Arp's image:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp335.jpeg
SDSS image:
http://astronomerica.awardspace.com/SDSS-25/NGC3509.php

The HST hasn't released a color image and I only found UV and IR images in their data base. The UV image barely shows the "red blob" though it shows well in IR so I used that to make a very noisy black and white image. Note the blob appears to be a background galaxy and the knots below the core of Arp 335 seem to be star clouds but could be the remains of a galaxy it is "digesting".

So three images, main image, annotated image and HST image.

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

Related Designations for ARP335

ARP336

Arp 336/NGC 2685 is an example of a polar ring galaxy though that's hard to tell from its classification as (R)SB0+ pec. It is probably the result of the merger of two spiral galaxies that were oriented at right angles to each other, one winding up around the other. This is a very nearby object, being only about 45 million light-years away. It is sometimes called the Helix Galaxy as the remains of one of the spiral galaxies seem to spiral around the other galaxy. Where the helix structure passes in front of the other galaxy it is seen as a dark feature but where it is away from the other galaxy it is a bright feature. It is also known as NGC 2685 and is classed by Arp under his "Miscellaneous" category. This is for those few he cataloged that were one of a kind. At least as far as the 200" Palomar telescope could see at the time. There is another famous polar ring galaxy but it is too far south so wasn't on the survey plates Arp used to make his catalog. Hubble took a famous image of it ( https://www.spacetelescope.org/images/opo9916a/ ) but I can't find one of Arp 336 other than a raw image. I find that surprising. A photo from Kitt Peak is at:
http://www.noao.edu/image_gallery/html/im0851.html
HST raw data: https://en.wikipedia.org/wiki/NGC_2685#/media/File:NGC2685-hst-R814G555B450.jpg

One note in NED says:
"NGC 2685 is perhaps the most unusual galaxy in the Shapley-Ames catalog. There are two axes of symmetry for the projected image; most galaxies have only one. The central, amorphous spindle resembles a normal S01 seen on edge. However, helical filaments surround the spindle. Because of projection effects, it is impossible to tell whether these filaments form complete circles around the spindle or whether they start somewhere on the spindle and spiral outward at right angles to its axis. The filaments are seen in absorption when they pass in front of the bright background, but they are luminous when they are not silhouetted. Note how the entire north-east end of the spindle is covered with the projected absorption lanes of the helix. A luminous external ring around the entire structure may be either a true ring or a complete shell seen in projection. Many questions are unanswered about this galaxy. Is the central feature a spheroid (with two axes equal as in a plate or pancake), or is it an ellipsoid like a cigar? What is the direction of the angular momentum vector? Is the external ring attached to the central regions, or is it separate?"

The blue blob of a galaxy off the bottom left of Arp 336 is SDSS J085530.07+584117.3. The spiral near the bottom is MCG +10-13-035. I find no redshift data on either or any other galaxies in my image. Arp 336 is located in Ursa Major under the bear's chin.

Arp's photo with the 200" scope is at:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp336.jpeg

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

Related Designations for ARP336

ARP337

Sometime, probably after January 11 and before January 19, the light of a type 1A supernova in the starburst galaxy M82 hit the earth. It wasn't "discovered" until the night of January 21 in England. A group of students got an unexpected introduction to what to do when an event such as this is first seen. You can read about it at http://www.ucl.ac.uk/maps-faculty/maps-news-publication/maps1405. I've seen images taken as early as January 19 that show it but those taking the images didn't realize what they had or didn't look at the data until days later. Earlier images likely exist. These are referred to as pre-discovery images. I first heard of it on the 22nd but it was cloudy. It sort of cleared Wednesday night, the 23rd of January (all times and dates are UT, not local time). I had rather poor seeing but took what data I could prior to moonrise. The temperature here was running down around -35°C when I started and dropped 3 more degrees while I was taking the data which meant my image scale changed adding to my processing steps. My red data was taken when the moon was brightening the sky though not yet risen.

Starburst activity creates many short-lived massive stars that go supernova after only a few million years of life. Such supernovas are called type II supernovae. So you'd expect such a massive star's death to be the cause of the supernova. But, just to be contrary I suppose, this is a type 1a which is caused by the sudden destruction of one or maybe 2 white dwarf stars. White dwarf stars are much less massive stars and live at least a billion years or longer. So the star or stars that caused this supernova predate the starburst activity in M82. Such supernovae are thought to be standard candles so if you know the apparent brightness as well as how much dust and gas between us and the supernova dims the light the distance to the supernova can be calculated. Thus this supernova might help better determine the distance to M82 which is currently put at about 12 million light-years. The problem is the light of a fresh type 1a supernova should be blue. This one is somewhat red. Not because the supernova is red but because it went off deep inside the dusty M82's disk. Dust reddens starlight same as it reddens our sunsets and sunrises. This will make estimating the loss to dust and gas rather difficult. I'm sure all sorts of methods of adjusting for this will be tested by this event.

M82 is also Arp 337 so I've added another supernova to my collection of Arp galaxies. A surprising number of them in my collection were caught with supernovas including M51 and M101 and about a half dozen others. I've lost count so need to go back and look that count up. Seems peculiar galaxies that made his list are above average in the number of their supernovas by my rather unscientific survey.

I've made an annotated image showing the surrounding galaxies, galaxy clusters, and quasars. I found this field particularly difficult to work with. Many of the quasars listed in NED, as well as some galaxies, had vague coordinates. Often there was nothing close to the right magnitude within the error circle or even well beyond the error circle. Rather than guess I didn't include these vague positioned objects. Even when I could identify the object it was sometimes listed as both a quasar and a galaxy yet of typical galaxy distance and sometimes showing a slight disk rather than the point source of a quasar. I listed these as both Q and G often with a question mark. NED usually preferred the quasar designation even when a small disk is seen. While NED listed about twice as many galaxy clusters as I show I only listed those with a Big Cluster Galaxy listed in NED such that I could pin down its location. Some used photographic redshift, designated with a p after the light travel time figure, for the cluster but spectroscopic redshift for the BCG. The latter is likely more accurate though in these cases they were in rather close agreement. Many times I find a wide difference but not with these.

The supernova is expected to continue to brighten for a week or maybe longer. Due to the extensive light of the galaxy around it, I was unable to get a good magnitude estimate. There are tricks for adjusting for this but I didn't take the time for them. Most estimates put it at about magnitude 11 or a bit brighter. It might reach 8th magnitude by some predictions. Time will tell if those predictions come true.

M82 was discovered by Johann Bode on December 31, 1774 the same night as he found M81. Like M81 Koehler may have seen it sometime between 1772 and 1778 but didn't record it until 1779. Pierre Méchain then saw it in August 1780 and likely reported it to Messier who observed and recorded it on February 9, 1781. William Herschel then observed it on September 30, 1802. It is in the original Herschel 400 Observing Program. My notes from April 15, 1985 on a humid night with my 10" f/5 Cave Newtonian at up to 150x reads: "Bright large streak with an even brighter central core. It can even be seen in my 8x50 finder on this rather low transparency night. Several dark lanes are seen near the core. It takes high power well though, this night I'm limited to 150x due to low transparency."

For more on M82 see: http://messier.seds.org/m/m082.html

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

Related Designations for ARP337

ARP338

Arp 338 is the most obscure entry in Arp's atlas. It is also the very last entry. It is, however, the only one NED lists only by its Arp number giving no other designation. Though likely there is a second entry for it as shown below. It is in one of the other catalogs NED has entered into its database. However, it is listed as PGC 154807 in other catalogs with a magnitude of 16.1. While the bar-like feature is listed in The Sky as PGC 3094767 at magnitude 18.5. Arp 338 falls into Arp's miscellaneous class. It is located in southern Sextans. Distance is a bit uncertain. More on this in a bit. Even though the area is rich in galaxies, the Sloan survey doesn't cover this area. Nor could I find one paper discussing it other than one that lists it simply as one of Arp's peculiar galaxies and another that indicates it appears similar to one the paper is really about. So I'm coming up blank on this one.

As mentioned, The Sky 6, however, does list it as PGC 154807 but doesn't list it under Arp 338. The bar-like feature has a separate listing PGC 3094767. NED may list the bar as 2MASX J10105859-0755016. I say may because its position has error bars large enough to include the main galaxy. Also, it lists a magnitude of 16 which is right for the main galaxy but far too bright for the bar. I suspect it is just a second entry for ARP 338. I find a few references to Arp 338 being a double galaxy. But the way they read, it seems they are not seeing the bar as the second galaxy. Most see the very blue galaxy to the southwest as the one it is paired with. The Sky 6 says it is PGC 1010862. Arp was careful to include it in his image. NED considers Arp 336 a double galaxy but seems uncertain of its position. I'm used to the vast majority of its objects to be within a 0.5" diameter error circle. In this case, the error circle is 10 minutes by 7.5 minutes! It is a minute or so off center. So much for precision.

To me, the bar is a separate galaxy as the 2MASX entry suggests. It certainly is an IR source to be in that catalog and its coordinates match the golden core of the bar, not the main face on galaxy. Also, the bar seems to be a bit blue well away from its center just like a typical spiral galaxy would. The only problem is a lack of a dust lane you'd expect from such an edge on view. The 2MASX catalog does give a redshift of a bit over 700 million light years for whatever it is pointing to. What about the blue galaxy? There's no distance data for it either. In fact, it isn't in NED's database at all! Assuming a 700 million light-year distance for both galaxies I measure the disk galaxy at 120,000 light-years for its long diameter and the edge on at 80,000 light-years in length.

There appears to be a pair of interacting galaxies to the northwest of Arp 338. They appear to share a common envelope. There are two levels to this envelope. A bright inner one and a much larger faint outer one. Without any distance data, I can't estimate its size. The upper left one is in NED but with no redshift. The other one isn't in NED's database. In fact, most of the galaxies in this image aren't listed in NED's database. Only a very few have redshift data. All appear at about the same distance as the bar in Arp 338. If the bar is a separate galaxy in front of the other one then that one would be further away, how much further is unknown.

Normally in an image of an Arp galaxy NED will identify several thousand galaxies. So few were identified in this field I've noted each and every one by name and its distance when that is available. That's how little there is on this entire field.

Arp's image
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp338.jpeg

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

Related Designations for ARP338