ARP250

A few Arp galaxies are very photogenic, Arp 85 (M51) for instance, most are at best interesting. Then there are those so far away or so small they are the photographic duds. Unfortunately, Arp 250 falls into this category, in this case, because it is so very small yet could be two colliding small galaxies.

While there are two galaxies here only the one to the west is considered to be Arp 250 which he classed by Arp under Galaxies (not classifiable as S or E): Appearance of fission. It does indeed appear to be a galaxy that has been cut in half right through the core. Or else it is two spirals about to collide. It is only about 70 million light-years distant, two and a half times closer than Haro 1 in the lower left corner. It is a rather small galaxy. The only catalog entry for its "companion" to the east is in the PGC where it is listed as #2063674 at magnitude 17.5. My image is poor but it appears distorted so may be involved. There's just not enough information to know. In all, there's a dearth of data here. I figured its odd double nature should have generated some papers but I found none. Heck, Arp apparently didn't have anything to say on this one. At least I couldn't find any comment from him on it. Nor any by anyone else other than a visual sighting with a 25" scope.

After I wrote the above paragraph I'm finding some sources, such as NED consider the eastern two armed spiral as Arp 250. Same happens when I enter it into the STScI DSS server using SIMBAD to resolve the coordinates. Yet SIMBAD itself gives the western galaxy. Arp's image is framed to give equal prominence to both. The only object showing anything that could be construed as splitting would be the two colliding galaxies to the west.

Little information is available on anything in the image. The very blue tiny galaxy west (right) of Arp 250 is HS 0732+3529 at the same distance, 180 million light-years as Haro 1. HS stands for Hamburg/ESO QSO Survey. Apparently, it looked for compact blue objects as likely QSO candidates and found this galaxy in the process. NED lists no other catalog entry for it.

There's another very blue galaxy SE of Arp 250. Appears to be a spiral. Oddly no catalog I checked includes it. Is it too at 180 million light-years? I have no idea. I can't even give it a catalog entry.

Galaxy in Southeast corner is Haro 1/NGC 2415 classed by NED as possibly an irregular Magellanic galaxy. Redshift indicates a distance of about 180 million light-years. Seems large for a dwarf and while the spiral structure is distorted I don't see it as an irregular galaxy. Haro galaxies are blue with emission lines. It is thought paired with one or two other galaxies described as 22 minutes north which puts them out of my FOV. The only candidate, out of my field, I can locate is UGC UGC 03937 but it is 23 minutes NNE with a redshift distance of 190 million light-years. HS 0732+3529 is only about 17.4' away so may not fit though its distance and very blue color would seem to say otherwise. Only catalog entry anyplace for the one (or is it two) blue galaxies just to the west of Haro 1 is PGC 213406 with little other information. I see a wisp of stars below it but not quite connected to it. No nucleus to it. So is it a tidal arm pulled from this galaxy or another galaxy entirely, just one with no defined core? One reason Haro 1 looks distorted is there are three stars superimposed on its arm structure making them look more distorted than they really are. You have to look closely to see them. I wouldn't have noticed them except for one paper that mentioned them.

Haro 1 seems to have confused the keepers of the Hubble data archive. I checked the archive to see if Hubble had imaged Arp 250. I was happy to see two images. At least I'd have a black and white image. Nope. It was Haro 1. So I tried other catalog names for Arp 250. All brought me back to Haro 1 -- oops. So I tried Haro 1 and got a lot of images of it, none the two filed under Arp 250. Interestingly the mono image labeled Arp 250 was the best data. I then took color filter data from Haro 1 data and made the attached Hubble image of Haro 1. It's a tad better than mine. Though is it billions of dollars better? Hmm. NGC 2415/Haro 1 was discovered by William Herschel on March 10, 1790. It is in the second Herschel 400 observing program where it is described as "tiny." With a diameter of about 50,000 light-years, I'd not say it is "tiny." Just that it appears tiny from our distance but it is far larger than the two galaxies that make up Arp 250.

Just off the bottom left edge of the image is the galaxy cluster, ABELL 0590. There is a possible QSO just on my image. It is only 2.5 million light-years away. NED says it is a galaxy, SIMBAD says QSO. In my image, it appears to be a very orange galaxy right along the lower left edge of my image, NE of Haro 1 so I have to vote for the galaxy designation. Likely one with a very active nucleus.

http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp250.jpeg

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

Related Designations for ARP250

ARP251

This is one of Arp's least photogenic catalog entries. Big and bright it's not! You'll need the 2x enlarged view to see much detail in these apparently extremely distant galaxies.

Arp 251 is a triple galaxy in western Cetus. Arp classed it under Galaxies (not classifiable as S or E): Appearance of Fission. Probably because the two spirals appear connected and "trying" to split apart. More likely their arms overlap as seen from our point in the universe. Arp's comment: "Outside arms diffuse and bifurcate." The northern galaxies "bifurcated" arm appears more like a true arm and a detached star cloud. The southern arm appears split in my shot more than Arp's for some reason.

The northern galaxy is cataloged as 2MASX J00534840-1351148. The Kanipe/Webb book lists it as MCG -02-03-037 but NED says this is all three as it lists it as a triple. In any case, NED has little on it, not even a magnitude. The southern galaxy is 2MASX J00534765-1351358 and is listed at magnitude 15.1 but that's in near-infrared light (I band) and may not say anything about its visual magnitude. The third member to the southeast is anonymous, only being listed in the UK's automated plate measurement catalog as APMUKS(BJ) B005119.43-140753.8 which gives it a magnitude of 17.8 but no filter is listed. A note at NED on Arp 251 says the southern and southeastern galaxies are 16th magnitude. It doesn't give an estimate for the brighter northern galaxy. That's the extent of what I could find on these three galaxies -- virtually nothing. No distance measurement, little spectral data and fuzzy magnitude data. That's it.

Edit: Since the above was written I found one amateur page that cited a z value of 0.075300 (22575 kps). That would translate into a distance of about one billion light-years. Does that make this the most distant of his entries? Some say it is the most distant but as I can't find a redshift for others, I can't verify this.

The near edge on galaxy to the northwest is 2MASX J00533671-1349541. It has a magnitude listed at 16.4 and a redshift distance of just over 700 million light-years. The magnitude lists no filter. It is larger in angular size than the galaxies making up Arp 251. This could mean they are further away but it could also mean they are smaller galaxies in the first place and are really closer. There's no way to know. Most of the other galaxies in the image are only listed in the APMUKS catalog, only the one galaxy has any redshift data.

Even my The Sky database for Arp galaxies got confused and centered me on the near edge on spiral to the upper right. I checked this with SIMBAD and the DSS II plates which centered on a spot halfway between the two. I went with my database without checking further so it isn't as centered as I'd like. Also, this is about 13.7 degrees south nearly at my normal 15 south limit so seeing isn't very good. That's what I get for moving north to get dark skies instead of New Mexico or Arizona.

Arp's image: http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp251.jpeg

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

Related Designations for ARP251

ARP253

Arp 253 is a pair of probably interacting galaxies located near the western border of Sextans about 100 million light-years distant. At least that's the distance to the western galaxy which is also cataloged as UGCA 173. A secondary distance estimate puts it at 90 million light years. Since galaxies have motions besides that of the expansion of the universe the difference is really quite normal and expected. It is classed by NED as SB(s)dm? The eastern galaxy is UGCA 174. There are no distance estimates for it but likely it is truly interacting with UGCA 173 and thus at the same distance. It is classed as SB(s)m? Arp's only comment indicates there may be some stellar resolution or else HII regions. At that distance, the latter would most likely be what he was seeing. Arp classed it under Galaxies (not classifiable as S or E); appearance of fission. As with most galaxies in the classification, I don't seem to understand why he says that. Does he mean the two galaxies look like two rod-like bacterial splitting? They often move around like two train cars before splitting completely. Or is he referring to the various parts of UGCA 173?

The reddish round galaxy SW of Arp 253 is 2MASX J09430672-0518514. I have no information on it. Far more interesting is PGC027825, the "large" galaxy south of Arp 253. Its redshift puts it also at about 100 million light years indicating it is part of the same group. It is not mentioned by Arp but sure looks peculiar enough to have made his catalog. NED classes it as SB(s)d pec. It may also have interacted in the past with other galaxies in the group.

Above Arp 253 about the same distance as MCG -04-25-033 is south of it is 2MASX J09432459-0510450, a small round galaxy of unknown distance or classification. Toward the upper right corner is another orange galaxy just below and right of a blue star. It is 2MASX J09423777-0509328 at 750 million light years.

The orange galaxy near the left edge several minutes of arc below the top edge is 2MASX J09442604-0511330 at about 800 million light years. Above it, right in the top left corner is 2MASX J09442771-0508030, yet another IR strong galaxy. It too is at 800 million light years.

While there are a lot more galaxies in the image only those in the 2MASS survey are cataloged and I've listed all with redshift data. SDSS hasn't covered this region nor has Arp 253 been imaged by the HST.

The asteroid is (84901) 2003 TF13 at an estimated 17.9 magnitude.

The last blue exposure was 10 seconds too long as the object reached the mount's meridian limit. So there was a short blue trail on each bright star. I didn't even notice it until I was about to post this and suddenly saw it on the bright star to the lower right. At first, I thought it another asteroid trail until I realized fainter stars had similar trails. I only cloned out the bright one so the fainter ones are still there if you look closely enough.

Arp's image is at:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp253.jpeg

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

Related Designations for ARP253

ARP254

Arp 254 is a pair of interacting galaxies, NGC 5917 (MCG -01-39-002) and MCG -01-39-003/PGC 054817. They are located in Libra, about 96 million light-years away. Arp put them in his category for Galaxies: Appearance of Fission. I can't fathom how he sees these two as appearing to be dividing. Arp had no comment on the pair to help shed some light on this. NGC 5917 was discovered by John Herschel on July 16, 1835.

NGC 5917 is classed as Sb pec? and is the northern galaxy. It has a rather large faint outer halo and is somewhat disturbed. It is listed in the 2MASX catalog of InfraRed objects so likely has some dust heated by star formation we can't see. While sometimes a sign of interaction that isn't necessary. The southern galaxy with the two huge plumes is MCG -01-39-003. Redshift puts it slightly more distant but this is likely just due to relative motion rather than a real distance difference. It is classed as S0 pec. A note at NED indicates the northern plume reaches NGC 5917 and thus is a bridge. I certainly don't see that in my image nor in Arp's but if there would explain his fission category as he uses it mostly for galaxies that are apparently connected by a tidal stream of stars. The note also notes the system is "perfectly isolated". Maybe but I'd like to know more about LEDA 1017437 to the south of MGC -01-39-003. It is off the other plume and at 800 million light-years. With the plume headed toward it, I find it a "galaxy of interest", as the detectives say.

Kanipe and Webb have this to say about the pair. "This strange pair of galaxies is connected by a tenuous bridge, visible both in the Arp Atlas photograph and Richard Miller's image (above). Close examination shows that the interiors of both galaxies have been stirred by experience. Since the system is totally isolated in intergalactic space, the bridge and the disturbed appearance of the disks suggest a galactic sideswipe." Richard Miller's image, which includes a 2005 supernova is at http://www.338arps.com/arp_254.htm

I agree a sideswipe likely is the cause, however. The note above agrees to the note at NED. Could that note be the source of their comment? The note dates to 1963 so was likely known to Arp at the time he took his image. Could it also have influenced him to put it in the fission category? NED has nothing newer on the system which bothers me. Link to the note: http://ned.ipac.caltech.edu/cgi-bin/nph-datasearch?search_type=Note_id&objid=40559&objname=NGC%205917&img_stamp=YES&hconst=70.5&omegam=0.27&omegav=0.73&corr_z=1&of=table

When I first wrote this my monitor showed no sign of the bridge in my image nor any other including the ESO image below. Since then I've changed my mind as I do see it now in my image as well as the ESO image. Apparently, I was distracted by the hook to the arm thinking it hooked back which it seems to have done but some stars continue up in a very faint connection.
http://www.eso.org/public/news/eso0622/

Color data in my image is very poor. The object is low in my skies and spring fog off the lake really tore up the color frames. I took the color data over three nights under very different seeing conditions. I took all three colors each night but fog ruined each color 2 of the three nights. Only the color I took first that particular night got through. Even then green was really clobbered. I used it but wonder if I should have tried a pseudo green made from the red and blue instead. I'm so far behind in my image processing I didn't try it both ways.

The field is out of the Sloan Survey area but the VLT image is far better anyway. Still, I wish it covered the southern plume as well. Without Sloan data, only the "big and bright" galaxies in the field have distance data. I've included an annotated image with the distances to these in billions of light years. Only 12 galaxies in my field are even cataloged at NED, 7 with redshift data. Pretty meager field. I'm used to thousands in the field being cataloged.

Arp's image
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp254.jpeg

ESO-VLT image at full size
http://www.eso.org/public/archives/images/screen/eso0622a.jpg

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

Related Designations for ARP254

ARP255

Arp 255 is another in his category Galaxies (not classifiable as S or E); Appearance of fission. In this case, it does look as if an arm broke off though that is likely only illusion. Even Arp considers it a separate galaxy but does believe the faint tidal arm to the north is really the continuation of an arm of the bigger galaxy as he notes: "Faint arm extends beyond high surface brightness companion." The pair is otherwise known as UGC 05304. They show a red shift indicating a distance of about 565 million light-years. NED calls the smaller one a "late spiral" and the larger simply S? probably indicating there's no agreement as to what type of spiral it is rather than if it is a spiral as it is obviously one. Looks rather like SBc pec to my untrained eye. The arms are unusually red for a spiral except for a detached very blue segment that may be mostly massive star clusters but otherwise, show no visual hint of star formation due to the interaction. Though it may be hidden behind dust. There seems to be little on this pair. Down and to the right of the pair is CGCG 035-075 which has about the same redshift and is obviously part of the same galaxy group. Directly west past an orange star is a rather bright very blue "star". It is the quasar [HB89] 0950+080 at 9.3 billion light years. Directly below CGCG 035-075 is a large faint, nearly colorless smudge of a galaxy. It is LSBC D709-10, an irregular Magellan like galaxy about 150 million light-years distant.

The big galaxy to the left is UGC 05308. It appears highly distorted as well but it likely did not interact with Arp 255 as its redshift shows a distance of less than half the distance at 260 million light years. It too is classed S? by NED. I'm surprised Arp didn't put it in his catalog as well. A couple of the small blobs in the upper part of it are listed by the SDSS as being separate galaxies with no redshift data. One is a short linear fuzzy patch in its NW merging with a star cluster in the arm. The other is the star-like blue object directly east of this feature. It's possible these are just parts of UGC 05308 rather than separate galaxies. Or they could be merging with it and the cause of the tidal distortion in the galaxy or they are far behind it. Without redshift data, I can't tell. Edit: Since the above was written the short linear fuzz patch has been given a distance of 540 million light-years using the Friend of a Friend method. The other blob has a redshift of 550 million light-years. Both are considered by NED to be part of the Arp 255 group.

Below it is the lenticular-like galaxy 2MFGC 07657. It is at a redshift distance of about 545 million light-years so could be part of the Arp group. Above it is another lenticular-like galaxy but smaller that is at about 550 million light-years and another likely group member, SDSS J095323.73+075113.7.

The round orange galaxy southwest of 2MFGC 07657 is 2MASX J09531866+0748067 at 560 million light-years it is likely yet another member of the Arp 255 group. The smaller round galaxy just below 2MFGC 07657 is SDSS J095325.05+074859.9. It is much further away however at 800 million light-years.

The rather large blue galaxy top center is LEDA 087189, a 17th magnitude Sd galaxy about 140 million light-years distant.

I found several asteroid tracks in the image. I was perplexed though why one seemed fuzzy. When I ran an asteroid check on the image at the Minor Planet Center I got my answer. It is a newly discovered periodic comet (12/31/2008). I've noted the 6 asteroids and the comet on the annotated version of the image. Magnitudes are estimates of the Minor Planet Center. Magnitude estimates of the comet toward the end of March 2009 when this image was taken vary by 2 magnitudes. The Minor Planet Center made no estimate so I didn't include one. You can judge somewhat by the other asteroids but remember a fuzzy object is a lot brighter than a point source like an asteroid and speed of motion dims the trail the faster it moves. The faintest asteroid at magnitude 21.1 is right at my limit for a moving object. I may not show on some monitors. Note that some of these estimates appear in error. With one listed at 20.0 appearing fainter than two estimated to be even fainter. An asteroid doesn't get a number until it has been followed around a complete orbit. This is why some have numbers and some don't.

Maybe I should title this image James Bond meets Arp 255. Well Ian Fleming anyway, yes that Ian Fleming. That's the brightest asteroid in the image! No space so it's Ianfleming on the annotated image. The naming citation reads: (91007) Ianfleming = 1998 BL30
Ian Lancaster Fleming (1908-1964) was a British writer and journalist. Fleming is best remembered for creating the character of British Secret Service agent James Bond ("007") and chronicling his adventures in twelve novels and nine short stories.

Limiting magnitude for this image is about 22.6, rather typical. The galaxies are in southern Leo southwest of Regulus almost to the Sextan's border.

Arp's image
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp255.jpeg

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

Related Designations for ARP255

ARP256

Arp 256 consists of two interacting galaxies; MCG -02-01-051/PGC 001224 (lower) and MCG -02-01-052/PGC 001221 (upper) at a distance of about 355 million light years. Arp classed them as; Galaxies not classifiable as S or E; Appearance of fission. Using standard galaxy classification the upper one is classed as SBc pec while the lower as SBb pec? So both are considered barred spirals. One note says of the upper galaxy; "It is possible that it alone consists of two overlapping galaxies." Hubble has taken an excellent image of this pair, it is at: http://www.spacetelescope.org/images/heic0810ag/ I'm not sure if it answers the question about it being two galaxies or not. That blue knot between the cores of the two galaxies may be a third galaxy. It carries a redshift that is a bit higher than either of the two galaxy cores. It is about the same as the smaller area of blue stars north of the core of the upper galaxy. Thus there seems to be an overlay of blue stars with a slightly greater redshift (by about 40 to 80 km/s). Whether this is a separate system I don't know. More likely the difference is just due to rotation of the galaxy in a plane tilted a bit away from us. The lower galaxy MCG-02-01-051 has a very interesting tidal tail to the west and in the Hubble image, it too has some of these super hot blue stars that may really be related to the other blue stars rather than the galaxy itself. Note how wild its core is as seen by Hubble.

The entire field is rather interesting and contains one of the most distant galaxies I've ever imaged directly, It's the distance of quasars, not galaxies. Per NED it's redshift puts it a bit over 10 billion light-years away! Did galaxies large enough to shine at 20th magnitude exist in a 3.5 billion year old universe? That seems pushing it, though Hubble has shown large galaxies coming together far faster than we had expected. There's one "but" in this. Seems the redshift distance has been determined photometrically rather than spectroscopically. Thus there's room for a very large error if some assumptions are wrong. The galaxy is directly below Arp 256 near the bottom of the page. Many more distant galaxies and a couple quasars (one quasar candidate is even further away than the galaxy but not by much. There are two asteroids in the image as well. Rather than try to point all this out I've just attached a second annotated image. Quasars are noted with a q in front of the distance. The other distances are for galaxies.

This pair is located at the western end of Cetus the Whale and thus is rather low in my sky reducing my ability to see fine detail. The image is a bit fuzzier than I'd like because of this.

ARP'S IMAGE
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp256.jpeg

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

Related Designations for ARP256

ARP257

Arp 257 is a double galaxy in Hydra about 170 million light years distant. Arp classed it in his category, Galaxies (not classifiable as E or S): Irregular clumps. for once I can sort of agree on the not classifiable as E or S part. I'm not sure what the clumps are he speaks of. Likely it is the two blue blobs leading from the lower galaxy to the upper. Arp's comment reads; "Galaxies joined by segment of thin arc."

Both galaxies are cataloged as UGC 4638. But they do carry separate entries in the MGC catalog. The southern being MGC +00-23-005 which is described as a disrupted spiral (?) with a chaotic outer disk, main body 0.8' x 0.5'. NED classes it as S pec. The upper galaxy is MGC +00-23-006. NED says of its classification "spiral ?"

The blue color of both would indicate spiral or irregular and certainly indicates massive star formation is currently going on in both due to their tidal interaction. SIMBAD considers the larger of the two other galaxies to be "Part of Galaxy" and gives it the designation VV 041c. VV 041a and b are the two galaxies Arp considered as Arp 257. Is it part of the upper or lower galaxy? Looks rather like a separate galaxy to me. What about the fourth galaxy? Wish I knew. Neither NED nor SIMBAD mention it. The blue galaxy north of the Arp 257 group near a bright star is anonymous. To the west of Arp 257, nearly 9.5' away, is 6dF J0851002-022201 and is only half the distance of Arp 257 at about 85 million light years. There are no other galaxies with a distance estimate that I could find. This region is rather obscured by our galaxy's dust. For that reason, it has been little studied. Sloan stays away from such regions so hasn't covered it nor is it likely to in a future survey.

I didn't check around my field of view. I wish I had as just out of the image at the top is UGC 04640 a much larger galaxy than those of Arp 257 but at the same distance. In fact, the redshift is virtually identical so it is likely related. I usually check for such things before taking the image but didn't this time -- the one time I should have.

Arp's image:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp257.jpeg

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

Related Designations for ARP257

ARP258

Exactly what constitutes Arp 258 is a bit difficult to determine. Some sources are quite inconsistent from page to page in this regard. Some say it is just the chain of debris plus one galaxy at the bottom all collectively known as Hickson 18 or UGC 2140. Others leave off the bottom galaxy as it is a distant interloper. One that leaves off the bottom one on one page includes it on another and adds the two anonymous galaxies to the west. So take your pick.

The upper string carries three entries in the PGC/LEDA catalog 10042, 10043 and 10044 top to bottom. The top two are blue, 10044 is more orange. The redder galaxy below this is 10046 in that catalog. The first three have a redshift indicating a distance of about 175 million light-years while the bottom one shows the much greater distance of 445 million light-years. Way too big of a difference to be considered part of the group. While the upper part carries 3 PGC numbers it is made up of a lot more pieces. Some papers say there are 6 galaxies in this group. I could argue for even more as the upper part alone has 7 bright condensations. The lower part is drawn out into two longer pieces or is it just one piece darker in the center? Then there's the debris cloud that is spread across the whole mess. I can find no data on the two galaxies to the east. They, like PGC 10046 appear unrelated to the smash-up. One is a near starlike elliptical and the other an S0 galaxy. PGC 10046 is classed as SB0. Arp's comment on the blue parts: "Resolution into knots on larger galaxy." Or is he referring to the two parts of the somewhat orange one that's so torn apart? I don't know.

PGC 10042 is listed as Im. Exactly how much of the upper part of this mess it is considered to be is hard to tell. Its dimensions of .6 to .7 minutes covers most of the northern pieces, 6 in all.

PGC 10043 seems to consist of the northern part of the elongated double southern half. It too is classed as Im but is shown as .7 by .4 minutes which must include some of the debris cloud.

PGC 10044 is another mystery. NED considers it the entire group of 3 galaxies while most other sources consider it the bottom part of the three. In any case, the bottom part is also classed as Im. Likely because they had no idea what the heck is going on here.

Something has certainly disrupted whatever this was before the encounter. So there were at least two objects here. We now see many pieces. Likely they will combine to form one elliptical galaxy in the future. But for now, it's one big mess. I couldn't find many papers trying to straighten it all out either. A couple however referred to it as two disrupted galaxies, another a faint spiral and fragments and yet another as 6 galaxies. Based on the color in my image, it appears the 2 galaxy idea might be right as one is somewhat blue while the other reddish. To me, the scientific name for that type of agreement is to call it a mess. Though it deserves an adjective I can't use here.

The galaxy to the SE of the group is 2MASX J02393096+1819089 ID Other than it being an IR emitting galaxy in the 2 micron IR survey I have little on it. The same applies to the smaller galaxy to its southwest. While a few other IR galaxies are in the field none have much information other than position. At least I can identify the 3 asteroids in the image!

ASTEROIDS
(36784) 2000 SU11 18.9 Upper right from Arp 258
(68306) 2001 FU103 19.6 near left edge a bit north of 258
(718) Erida 15.9 Below 2001 FU102, nearly starlike, bright, below two stars of similar brightness forming an equilateral triangle. It is slightly reddish in color which surprised me. I must have caught it a the end of its retrograde loop when it was nearly stationary in the sky.

Directly east of Arp 258 is what appears to be another asteroid. It isn't one. I suspect it is a distant edge on galaxy. It just barely shows in the POSS two plates. This isn't an area covered by the SDSS survey. It is too faint for other surveys so, for now, is anonymous.

Arp's image:
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp258.jpeg

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

Related Designations for ARP258

ARP259

Arp 259/NGC 1741/Hickson 31 is a tight group of galaxies about 180 million light-years away in the constellation of Eridanus just north of the Witch's Head Nebula (far too large for me to try imaging). Arp put it in his category Galaxies (not classifiable as S or E): Irregular clumps. His comment reads: "Material extends SE toward peculiar round spiral." That is IC 399 which is also the G member of Hickson 31. NGC 1741 was discovered by Édouard Stephan on January 6, 1878. IC 399 was discovered by Rudolf Spitaler on February 25, 1892.

Hickson considered this to be at least 6 galaxies, A-F but some put IC 399 in as G. NED includes many more. I've shown most of them on the annotated image but in a couple cases, the positions had a 5" error circle making it hard to tell which was which. In one case H1 and H2, I gave up and drew one point for both. Others I saw nothing in the circle so didn't include. Most had redshift distance. All but one of which put it at about 180 million to 185 million light-years. One Hickson 31D was very red in color, often a sign of distance due to interstellar reddening. Sure enough, it is 1.2 billion light-years distant and obviously just a bright line of sight galaxy far larger than any in the true group. Some members of Hickson 31 are considered part of NGC 1741, parts A, B, C, and D. Though again, D is obviously only a line of sight member.

It appears to me that many of the other members NED includes are really just massive star formation regions created out of the debris of the interaction of A, B, C and possibly E. G is certainly a separate galaxy. F could go either way but I prefer it a small dwarf with massive star formation creating the strong IR light it emits.

Then there is the one that NED labels as Q! I have no idea what happened to all the rest between G and Q. It's only other catalog name I could find is NPM1G -04.0219. Since this field is out of the SDSS survey only a few galaxies in my image are cataloged. Just yesterday, as I type this the Sloan 3 data was released. It covers some other areas of the sky besides that of previous Sloan surveys but I don't think this field qualifies. Still, I wanted to check but the website seems to have new site jitters and refused to do anything when I entered this field. Just timed out doing nothing. Fields I knew were in the survey did load so apparently, that is its way of telling me I was out of bounds as I expected.

The annotated image gets a bit busy trying to point to all the pieces NED records with the HCG31 label. To save space I left that part off and only included the suffix, add HCG31 to all. Most had redshift data. A few of the faint pieces didn't. I didn't distinguish those. Only D is noted with redshift distance since it was obviously a line of sight member. Other galaxies not considered members by NED are labeled only with their redshift distance using 5 year WMAP data and the time travel distance. Many galaxies, including the large low surface brightness one NE of Arp 259 weren't in NED at all. Very frustrating but it wasn't an IR strong galaxy so not picked up by the 2 micron survey which most of the field relies on.

The below chart listS the catalog designation of the members of this group.

NGC 1741A HCG 31A Sdm 186
NGC 1741B HCG 31B SB(s)m pec 189
PGC 16573 HCG 31C SB(s)m pec 184
PGC 16571 HCG 31D Sbc 1169 Obviously not a member
HCG 31E no class 183
GALEX 2732886767084503642 HCG 31F 181
IC 399 HCG 31G IAB(s)m pec 182
HCG 031Q 187

All are between 181 and 189 million light-years distant by redshift.

Hubble Space Telescope image of A-E, north sort of up It's a "little" better than my image for some reason.
http://upload.wikimedia.org/wikipedia/commons/0/05/HCG_31_HST.jpg

Arp's image oriented west up rather than north up as mine is
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp259.jpeg

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

Related Designations for ARP259

ARP260

Arp 260/UGC 7230 is a pair of interacting galaxies in southwest Coma Berenices a bit north of M98. They are thought to be about 340 million light-years distant. Arp put them in his classification Galaxies (not classifiable as S or E): Irregular Clumps. I suppose that refers to the two star clusters north of the core of the western (right) member. His comment on it reads: "Possible lines of faint condensations extending south." Does this refer to the large southern plume from the western member? The attached Sloan image seems to break it up into linear features.

The pair is listed in many catalogs as a pair. I didn't find a separate designation for them. So they are known as UGC 7230 or MCG +03-31-077 or KPG 326 etc.

NED classes both members as Sc. I'd think they both are worth a pec. designation but apparently NED doesn't agree. The western part of the two star clusters north of the core of the western member does have its own entry in the Sloan catalog, SDSS J121337.45+160718.0. Though it is marked at NED as being part of the galaxy, not a separate galaxy.

Arp 260 is a member of a group of galaxies at about 340 to 360 million light-years years by redshift. The actual distance is probably closer to 350 million light-years averaging out their redshifts. All are marked on the annotated image that are in NED. Several are very blue like Arp 260 though far smaller. Something has happened to trigger all that star formation. Group members include the more ordinary spiral CGCG 098-102 at the upper right. I'm rather puzzled that it is classed as SA0. I'd think SAb would be more reasonable. It has one somewhat blue arm but otherwise is a pretty old star looking spiral. The other old star looking galaxy is VCC 0075 west and a bit south of Arp 260. It looks rather like an elliptical galaxy but NED shows it as S0? If so it must be seen end on to be so elliptical looking. At the very bottom is a blue member of the group LEDA 1497645, also known as AGC 226038 and ALFALFA 1-171. No, it's not a member of the Our Gang movie series. ALFALFA stands for Arecibo Legacy Fast Arecibo L-band Feed Array. Someone was having acronym fun it would seem. In any case, it is obviously a strong radio source. AGC stands for Arecibo General Catalog so that scope put it in two of its catalogs. I couldn't find anything at NED on it, however. Must be a lot going on there, however. It's strong blue color would also indicate lots of new stars being created there.

NED shows a galaxy cluster at 2.7 billion light-years, MaxBCG J183.37186+16.06813. They show it as having 16 members. The center of the cluster is at the position of a very red galaxy southwest of Arp 260. The galaxy is 2MASX J12132924+1604054 and has a redshift showing it to be 2.7 billion light-years distant. The cluster has a photographic redshift distance of 2.6 billion light-years. I've noted it on the annotated image as G/GC with both distances shown. I don't know if the smaller red galaxy just east of the marked one is a member of the group. I suspect it is but NED doesn't give me enough information to be certain of this. There are several galaxies at the 2.7 billion light-year distance in the image. I assume they are members of this group. No angular size is shown for it.

There are some galaxies I'd like to know more about. The large, but faint blue galaxy at bottom center is SDSS J121411.39+155759.5. I have no distance data on it or anything else of much use to tell how it might fit with anything in the field. The Sky shows it as PGC 39076 and classes it as S?. I don't see any hint of spiral structure but my exposure time didn't collect much to go on. It is blue like many spirals but that isn't sufficient to call it a spiral.

Arp's image
http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp260.jpeg

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

Related Designations for ARP260