NGC4639

NGC 4639 and NGC 4654 may be an interacting pair in northern Virgo (top of the frame is in Coma Berenices) about 62-63 million light-years distant by redshift. Tully-Fisher measurements, however, say they are at very different distances and not interacting. NGC 4639 is a Seyfert 1.8 galaxy so has an active nucleus. This could indicate it has been involved in some interaction recently -- or not. If it was was the culprit NGC 4654 or maybe even closer PGC 4710? Or some other galaxy out of my field. Vollmer in a 2003 paper claims the two had a close interaction some ~500 million years ago that accounts for some of the distortions in NGC 4654. This only works if the Tully-Fisher distance estimate for NGC 4654 is very wrong.

This brings us to NGC 4654 which would fit nicely in Arp's category for galaxies with wind effects. In this case that is likely a good description as it appears the galaxy is being strongly hit by ram pressure due to its velocity through the intergalactic medium. This explains the off-center nucleus and distorted southeast end of the galaxy. Vollmer in the same paper says both interaction with NGC 4639 and ram pressure are to blame for the galaxies odd features. You can read the paper at: http://www.aanda.org/articles/aa/pdf/2003/05/aa1680.pdf. Note he puts the distance to NGC 4654 at the Tully-Fisher estimate of about 17 megaparsecs (55 million light-years).

Both galaxies were discovered by William Herschel on April 12, 1784. NGC 4639 is in the second H400 observing program while NGC 4654 is in the original program. My notes from that make me wonder what I was drinking that night. Maybe it was just due to recovering from tax season as I was a practicing CPA at the time. My notes from April 23, 1985 under fair to poor conditions with a bright moon at 50x in my 10" f/5 reflector read: "Interesting, fat, oval galaxy with sharp pointed ends. Seems to be near edge on. In the field with NGC 4639. Maybe I can blame the moonlight? Even then I can't reconcile my visual description of "pointed ends" and "near edge on" to this image.

Some things in the annotated image need a bit of mention. East of NGC 4639 is a triple galaxy, PGC 42788 and ASK 408987.0. PGC 42788 is two close galaxies -- maybe. Note the line points to a position a bit west of both of these two. That's the position NED gives but then says that is plus or minus 2.5 arcseconds. So is it pointing to all three? The position for the ASK galaxy is precisely that of the western of the three galaxies. Note it has a plume to the northwest. It is likely the three are an interacting group half again further away than the two NGC galaxies.

I found no distance estimate for the dE0 galaxy PGC 42821. North of NGC 4639 is PGC 42731. It is listed as dE1? Yet has a redshift that puts it 1.17 billion light-years distant. If so this dwarf is over 100,000 light-years across, possibly larger than our galaxy! So either it isn't a dwarf or the redshift is in serious need of revision.

Further north is ASK 408994.0. It appears in my image to be a galaxy hiding behind a star to its southeast. But it is really a very bright galaxy with a plume to the northwest. Somehow my processing hid its real identity though the starlike part is oval giving away it isn't a star. Still, I thought it two galaxies until I looked up its image in the Sloan database.

Galaxies without a common designation other than its coordinates are just listed as G. Turns out all are fainter than magnitude 20.0. Quasars and candidate quasars are indicated by Q or CQ as they too have nothing but coordinate listings which really clutter up annotated images. When look back distance based on redshift is getting into rather iffy distances I also provide the redshift z value which is a better distance indicator at large distances as the look back distance is neither a valid estimate of its current distance or its distance when the light left it. It just measures how long the light took to get here. For the quasar listed at 10.51 billion light-years and a z of 2.072042 its distance when the light left it was only 5.7 billion light-years and its "current" distance ("current" has no real meaning in a relativistic universe) of 17.6 billion light-years meaning it is now too far away for its light to ever reach us as the expansion of the universe in the 10.51 billion years the light took to reach us the quasar was carried 17.6-5.7=11.9 billion light-years from us, thus its average velocity is greater than the speed of light and still increasing. No this doesn't violate Einstein's speed limit of the speed of light. That says an object can accelerate faster than the speed of light as that would require more than infinite energy. Here space is expanding rather than the galaxy accelerating so the rule doesn't apply.

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

Related Designations for NGC4639

NGC4643

NGC 4643, located in central Virgo about 77 million light-years distant, is, at first glance in most images, a rather normal but featureless barred spiral as seen in the Sloan Survey image attached. Looks can be deceiving, however. When the image is really stretched beyond normal, even in my very short 40 minutes of exposure time it turns into a polar ring galaxy. Also, the disk has a nice ring with a diameter exactly that of the central bar. This ring gives it the "r" in its classification of SB(rs)0/a Linear. It is also responsible for it being classed both as S0 and Sa. Outside this ring is a nonconcentric arc. It is concentric for much of a bit over 180 degrees it covers but note it is much closer to the inner ring at the northwest end of the bar compared to the southeast end of the bar. But it is its polar ring that nearly all imagers of this one miss. It is at nearly right angles to the bar extending far to the Northeast and southwest of the faint outer envelope.

Assuming the 77 million light-year distance the central bar is 40,000 light-years long. The major axis of the disk as it is usually seen is 107,000 light-years across. Include the polar ring it is a whopping 228,000 light-years end to end. A very deep image of it taken with the Australian Schmidt camera shows the ring well. A negative view is at: http://203.15.109.22/images/deep_html/n4643_d.html . The link may be broken

The polar ring is likely due to some galaxy that merged with it leaving the polar ring as evidence of its destruction. This likely is also could be the cause of its LINER active core though new studies show white dwarfs can cause the LINER spectral effect.

You know the disk of the galaxy is thin and mostly dust free when a galaxy cluster at nearly 4 billion light-years shines right through the disk.

I'm not at all confident of the colors of the fainter parts of the galaxy. Conditions like usual for this spring were poor. The fainter parts in the color frames were well into the noise. I seem to show the outer shell that's rarely imaged as slightly red, redder than the inner disk. This may be noise. I need more and longer color subs under better conditions to be sure of the color.

The temperature changed during this image so I had to use RegiStar to resize and align the image. It normally does a perfect job. This one however completely threw it for a loop. Some stars that were only a second or two out of alignment suddenly were 30 seconds out of alignment one way or another. Two close by could be moved in very different locations. This was the red data. All the other frames aligned perfectly but red seemed to align randomly. I rebooted the computer thinking something had messed it up. I tried ordering the frames differently and many other things but it was always the two red frames that were far out of alignment in a random way. Though both reds aligned with each other just fine. This meant I had to do a lot of work moving the stars into position. The vast majority aligned correctly but about 150 scattered sometimes up to 30 seconds of arc from where it should have been while nearby stars were perfect. One thing I didn't try was to reinstall the program. I may have a corrupt installation though when I tried other images all worked as it should. Many stars and galaxies are only sort of aligned. I'll try again if I ever get the program to read the red frames correctly.

The annotated image shows many background galaxies, quasars, quasar candidates (UvES) and one Narrow Line Emission Galaxy all with redshift data. The galaxy clusters all used only photographic redshift noted by a "p" by the distance, same with the UvES entries. 5 asteroids also snuck into the image. All rather faint. Their details are in the annotated image. Near NGC 4643 to the northeast is a pair of apparently interacting galaxies at 1.10 and 1.11 billion light-years. The northern one looks like a comet with a fat but short tail. The companion is a compact galaxy and shows no distortion. Could it have the mass needed to disrupt the less dense probable spiral into its comet-like appearance? I need a lot more resolution than my skies allow to get any hint of what's going on with these two.

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

Related Designations for NGC4643

NGC4656

NGC 4656, the Hockey Stick Galaxy, is a highly disturbed galaxy or galaxies depending on who you read, located in Canes Venatici. It carries two NGC numbers, NGC 4656 which refers to the main core region and NGC 4657 which refers to the bright northeast end. While many papers through the 1980's and even a few into the 90's call this system an interacting pair most today feel it is just one highly distorted galaxy that came too close to nearby NGC 4631 and its distorted satellite NGC 4627. Its redshift puts it a bit over 40 million light-years away but most sources put it and NGC 4631 about 25 million light-years away.

NGC 4656 was discovered on March 20, 1787 by William Herschel. My entry from the original Herschel 400 program using a 12.5" f/5 scope at up to 150x on an excellent desert night reads, "Somewhat fainter than NGC 4631 but contains more detail. At 40x hook looks like another galaxy but at 150x the true nature of the hook becomes visible as a bunch of star knots on the end. A fantastic galaxy with a more fantastic neighbor! These objects need the 12.5" size to really appreciate them. My 10" which normally isn't far behind the 12.5" doesn't begin to show what the 12.5" sees in this galaxy." Apparently, I was rather impressed by it all.

This is a retake for me. I took it back when I was first getting into color CCD work. The results were very poor to put it in a good light. In this much better image, it appears the northeastern end is full of massive star clusters likely triggered by the interaction with NGC 4631. Two of the massive clusters at the northeastern end and to the southwest carry separate designations as galaxies in some catalogs. Though LEDA 4546890 is designated a star cluster by NED. SDSS J124348.72+320813.8 toward the southwest end clearly resolves into a cluster of stars even in my image NED carries it as a galaxy.

Several true galaxies can be seen through NGC 4656. I was surprised the nearly detached plume far to the northeast didn't seem to carry any separate designation that I found.

While there are a lot of faint background galaxies few had redshift distances noted at NED. Those few that did are shown in the annotated image. One I happened across that seemed to be in a small group of galaxies wasn't even in NED which earned it a question mark label. In processing the image I noted a really red star below a white star north of the core of NGC 4656. It turned out to be a super red galaxy 3.8 billion light years distant. I can't recall any galaxy this red before. Other galaxies in the image even further away aren't dust reddened as much as this one. It is an IR rich galaxy, 2MASX J12440504+3217580, though such galaxies often aren't very red in the visual spectrum.

The annotated image is an earlier process of the image and a bit darker but shows everything so I didn't redo it.

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

Related Designations for NGC4656

NGC4666

NGC 4666 is a very active galaxy though doesn't look it in ordinary light. Seen in X-rays however it is a different story. While not listed at NED as a starburst galaxy it is one. This has resulted in a "super wind" of very hot gasses coming from the core of the galaxy and blowing away from it at high speed. There's a lot on this on the web. One article is here: https://www.eso.org/public/usa/news/eso1036/ It refers to the galaxy cluster in my annotated image toward the bottom of my image.

What attracted me to it was it was in the 2MFGC as a flat galaxy. It's somewhat unusual for a starburst galaxy to have a small central bulge. So I was surprised to find that it was such an active starburst galaxy. While NED classifies it as SABc:; I see no bar. Neither does the NGC Project that says it is Sc but Seligman says SBc? again with a bar. Seen rather edge on it is hard to tell who is right. The galaxy was discovered by William Herschel on February 22, 1784. It is in the original Herschel 400 observing program. Another reason it was on my to-do list. My notes from April 23, 1985 under poor conditions with ground fog using my 10" f/5 says simply: "Highly elongated galaxy, otherwise little noted. Hint of two other galaxies in the field but they are very difficult to see through the fog." I assume those were the other two NGC galaxies in my image. I was using only 50x due to the conditions. I find distance estimates in published papers running from 60 to 80 million light-years. The latest says 80 so using that I get a size of a bit over 115,000 light-years so a rather large spiral. It is located in Virgo a bit northeast (1.3 degrees) of Porrima (Gamma).

To its southeast is NGC 4668. It is listed as Sb(s)d: by NED though it looks rather disorganized to me. Seligman says SBcd? while the NGC project says SBcd Irr. I can agree to the Irr part. NED shows a star cloud in it as a separate galaxy. I've noted it on the annotated image but am quite sure it is just a star cloud in the galaxy. It was discovered on April 11, 1787 by William Herschel. Apparently, he didn't see it when he recorded NGC 4666. It's not in either of the Herschel 400 observing programs. Assuming a 90 million light-year distance it is about 40,000 light-years across, rather typical for this type of galaxy.

The other NGC galaxy in the image is NGC 4653. It too is a William Herschel discovery. He found it on April 11, 1787 the same night as NGC 4668. He scanned by declination letting the earth's rotation bring objects into view. NGC 4653 and 4668 may be just far enough south of 4666 that these weren't in the scan that picked it up. NGC 4653 isn't in either Herschel 400 program. NED classifies it as SAB(rs)cd. The NGC project says simply Sc while Seligman says SBc?. So again there's a disagreement over the galaxy having a bar. This galaxy has a lot of detail but the night I took this image was so poor much of it is lost. Assuming its distance is 140 million light-years I get a size of 113,000 light-years thanks to its faint outer structures.

One distant galaxy to the west of NGC 4666 is ASK 001562.0. At 2.76 billion light-years I can't see much detail. It is listed as being a XBONG galaxy. That is an X-ray Bright Optically Normal Galaxy. Odd but that seems to describe NGC 4666 as well. Another rather unusual label is found east of NGC 4666, RQQ AGN which stands for a Radio Quiet Quasar. The AGN label is found on most quasars as they are the ultimate active nucleus but since NED included it I did too. Quasar is a short way of saying quasi-stellar radio source so a radio quiet one is unusual.

There were quite a few asteroids in the image that I'd normally show but this was taken under very poor transparency, only one showed up enough to point out. That only barely. But most of this spring has had poor transparency so to get anything at all I had to endure it, unfortunately. Didn't help that seeing wasn't very good either. Stars are wonky as it was drizzling shortly before this was taken. After it quit due to the short nights of May I didn't wait for the scope to equalize (takes about 30 minutes which I don't have this time of the year being so far north). Tube currents then play havoc with star shapes.

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

Related Designations for NGC4666

NGC4669

NGC 4669 is a huge edge on spiral galaxy in Ursa Major just under the handle of the Big Dipper that is about 230 million light-years distant. It is part of a group of galaxies at that distance. I couldn't find any designation for the entire group. Parts of it carried various names such as HDCE 0726, LDCE 0914 and HARO 32 Cluster. At first glance, NGC 4669 looks rather normal but its part north of the nucleus is about twice as long as its southern part even if you ignore the huge faint northern extension. Too bad we can't see it at a better angle to understand what is going on. Its full length is about 186,000 light-years making it one of the largest known spiral galaxies. Is that north part a plume from interaction with another galaxy? I found nothing on it which surprised me. Note also the dust lane to the south is normal but the lane to the north suddenly narrows and curves in a shallow arc first to the left then right. Very odd for a galaxy seen this close to perfectly edge on. It is likely related to the faint extension beyond it.

To the west is UGC 07905 an obvious pair of interacting, very blue, galaxies Both are described as peculiar with the southern member listed as being a starburst galaxy as well. The northern galaxy has the more interesting plume, at least seen from our angle. Why Arp didn't find room for this pair in his list of peculiar galaxies I don't know. It would have fit under several of his categories.

There are two other NGC galaxies in my frame (others at similar redshift lie outside my frame making this area a good one for those with larger fields of view). They are the S0 like NGC 4646 to the west and the barred spiral seen at a near edge on angle, NGC 4675, to the southeast. These are more normal sized spirals of about 60,000 light-years and 100,000 light-years respectively. The smallest is ASK 240169.0 at only 7,000 light-years.

NGC 4669 and NGC 4675 were discovered by William Herschel on April 14, 1789. They are not in either H400 program. NGC 4646 was also discovered by Herschel but on March 24, 1791. It isn't in either program.

I've annotated all objects with known redshifts at NED other than the galaxy groups as I couldn't determine which of the galaxies were in each of the groups.

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

Related Designations for NGC4669

NGC4689

NGC 4689 is a rather lonely galaxy in southern Coma Berenices. It may appear to have a very low surface brightness but that is due more to conditions. I took this on a night that started out great for the first luminance frame then fog rolled in but I'd gone to bed so didn't notice. Cloud sensor decided it wasn't too bad and let it go. The result is the very bright stars put a huge fog across much of the image costing me several magnitudes. This is why so little is seen in the background. It was wiped out by the fog. I needed to retake it but by the time I saw how bad conditions were it was too far west. Maybe next year. I did find bringing out detail difficult. It took a lot of work. I put it down to the fog. Then I looked at the Sloan image. http://skyservice.pha.jhu.edu/DR9/ImgCutout/getjpeg.aspx?ra=191.94&dec=13.76278&scale=0.792254&width=800&height=800&opt=&query=
it showed a very fuzzy image. Mine started to look much better though the fog cost me the faint outer parts of the galaxy seen in the Sloan image as well as in the one lone amateur image of it I found. Then I was reading notes on it at NED and this one said it perfectly. "Upon inspecting this image on this plate, one viewer commented, 'When man creates a sharper telescope, God will create a fuzzier object.'"

It was discovered by William Herschel on April 12, 1784 and is in the original H400 observing program. As I saw all in that with my 6" f/4 it can't be all that low surface brightness. Besides I was working under similar condition over 30 years ago when I logged it. My entry from my observation with the 10" f/5 on April 23, 1985 at 50x reads: "Rather oval splotch of a galaxy near two bright field stars. It seems 3.5x2.5 to my eye, somewhat smaller than shown in the guide. It's a very faint galaxy on an increasingly foggy (ground fog) night." Most cite its size at 4.3x3.5 minutes in size but I get only 3x2.5 minutes through the fog. Smaller than my visual estimate. Obviously, one to be revisited but that is unlikely to happen.

I had to put the galaxy high in the field because of the 6th magnitude A1V star, 26 Comae Berenices. It was creating ghosts no matter what I did until I moved the field to where I did. That used up a frame or two of fog-free skies, unfortunately. To the southeast of NGC 4689 is PGC 043216, a faint apparent dwarf galaxy. I couldn't find much of anything on it, however. Its relation to NGC 4689 remains a mystery to me.

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

Related Designations for NGC4689

NGC4699

NGC 4699 is a large flocculent galaxy low in Virgo. I can't find a consensus on its distance from us. NED puts it at 80 million light-years by redshift and has 4 non-redshift measurements that are quite inconsistent varying from 29 to 83 million light-years. Other sources give distances within this range. Averaging everything I found says 68 million light-years. The galaxy has a bright flocculent region most images pick up but it also has a very faint outer disk most don't pick up. Using the 68 million light-year distance I measure it at over 135,000 light-years in size but using just the bright portion most see it is about 75,000 light-years across.

Conditions were poor when I took this image both as to transparency and seeing. Add to that it is low in my sky and I missed picking up much detail in the inner portion of the galaxy. The spiral structure continues right to the very bright, but very small core. I lost the ability to see this except in the outer parts where it is not so finely structured. So the inner part that appears featureless is just due to bad seeing. Poor transparency limited my ability to pick up the outer faint regions. I suspect it is considerably larger than I was able to detect due to the poor transparency.

I was surprised to find this note at NED: "SB0: Bright nuclear point source embedded in elliptical bulge. The bulge is threaded by a short bar, oriented along the bulge major axis. The bulge/bar system is embedded in a smooth, featureless disk with the same P.A. as the bulge. No evidence of spiral structure." How did they miss the spiral structure? Everyone else sees it an SBb spiral.

Two asteroids are in the image. They appear quite dim for their estimated magnitude. Normally an asteroid brighter than 19.0 shows color traces in my LRGB images but neither do. Being low blue was a problem. Extinction was strong for blue compared to red. I knew that so took an extra blue frame to allow me to push the blue enough to retain color balance but it wasn't sufficient. The blue stack was still nearly twice as noisy as red and 50% noisier than green. Thus I don't trust the color data all that much. This is another for the reshoot list that likely will never be reshot.

It was discovered on January 18, 1784, by William Herschel. It is in the original H400 program. My entry from April 23, 1985 under poor foggy skies using no more than 50x with my 10" f/5 reads; "Bright, nearly round galaxy, otherwise featureless. I didn't see the bright nucleus mentioned as the whole galaxy seemed bright." Nor do I see it in my image but my night wasn't much better. Nor do I see it on the Sloan or POSS images. It is there, however. See this image with the galaxy stretched very differently than normal. https://cgs.obs.carnegiescience.edu/CGS/object_html_pages/NGC4699.html

Even with my poor transparency, I picked up a lot of background galaxies. Unfortunately only a very few had redshift data at NED. Why this region is so poorly studied I don't know. Two carry names that might lead you to believe they are connected with Hickson Compact Group 62 but that is a tight group of galaxies a couple degrees away. It is on my to-do list but likely will have to wait for another year.

14" LX200R @ f/10, L=4x10' RG=2x10' B=3x10', STL-11000XM, Paramount ME

Related Designations for NGC4699

NGC4710

NGC 4710 is located about 60-66 million light-years from us in Coma Berenices. It is classed S0-a by the NGC project and SA(r)0+? by NED. The (r) refers to the ring it appears to contain. It is seen edge-on, same as NGC 4762 (also an S0) in my previous post. Both have a ring-like region around the core and an extended much fainter disk. The main difference between them is that NGC 4762 is missing the expected dust lane while NGC 4710 has enough dust for several such galaxies but it is confined to the bright box-like core region which is highly unusual. This galaxy has been studied by the Hubble Space Telescope. They have a good explanation of what's going on at this link: http://www.spacetelescope.org/news/heic0914/

It was discovered by William Herschel on March 21, 1784. My entry for the original H400 program on March 14, 1985 on a night hurt by humidity using my 10" f/5 at 100x reads, "Small, faint, circular puff of a galaxy with a small but not starlike nucleus. A star two minutes east is the same brightness as the nucleus." While I see the star in my image this refers to and it does appear similar to the core the rest of the description indicates I was only seeing the very center part of the galaxy. I didn't give a size estimate to tell anything more.

While the box like core region with the "X" shaped bright regions is hard to see in the HST image it is rather obvious in mine. The tips of the "X" show as bumps above and below the normal rectangular core region. While not mentioned at the HST site I've seen other sources blame this on interaction with other galaxies. The Hamburger Galaxy NGC 3628 which is obviously interacting with its companion is a good example.

The other main galaxy in the image is IC 3806. Redshift puts it a bit further away at 79 million light-years. As redshift is greatly affected by random motion at this distance, its quite likely they are really both at about the same distance. IC 3806 is classed Sa? at NED. It has no obvious core but does have several bright regions near the core region. This would indicate a rather recent burst of star formation. Could that have occurred because of interaction with NGC 4710? No paper even hints at this as possible so apparently unlikely. Still, I can't help but wonder as both are irregular in some way. I'm not talking anything major here just they got close enough in the past to trigger the needed star formation in both to create their odd core regions.

The odd dust structure of NGC 4710, however, makes me wonder if it isn't due to it "digesting" a small, very dusty galaxy ala the Black Eye Galaxy. I sure wish we knew what it looked like face on.

One quasar is seen near the southwest end of NGC 4710. Otherwise I was able to find little of interest in my image. One minor galaxy cluster WHL J124952.9+145548 with 13 members and at an estimated distance of 4.6 billion light-years light travel time is located near the bottom of the image a bit left of center. It's position is 1 second of arc different than the galaxy I've marked it by in the annotated image. No distance is given for the galaxy however so that is represented as a question mark.

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

Related Designations for NGC4710

NGC4725

NGC 4725 is an often imaged galaxy in Coma Berenices. While red shift puts it at a distance of 69 million light-years most non-redshift estimates put it closer at say 41 to 43 million light-years. It is classified as SAB(r)ab pec Sy2 so has an active core and is classed as peculiar likely due to the large arm that wraps around it. It is a true one armed galaxy. How it got that way isn't known. The Seyfert 2 status would indicate a very active core with a feeding black hole. Could that be due to an interaction with another galaxy or one it ate? I found nothing on that, just a note that an arm like that can rotate either with the galaxy or against it. But since this is a true arm I assume it rotates with the galaxy though the note at APOD didn't say.

The galaxy was discovered by William Herschel, who else, on April 6 or 10, 1785. It is in the original Herschel 400 observing program. Two usually good sources, the NGC project and Seligman don't agree. Seligman has the earlier date.

My notes on NGC 4725 taken with my 10" f/5 on April 23, 1985 under fair but humidity dimmed skies with moonlight bothering using 50x reads: "Large, oval galaxy with a star-like nucleus. Two other very faint galaxies are in the same low power field."

One of the galaxies I mention must be NGC 4712 that was discovered by John Herschel on March 28, 1832. It is the other more normal looking spiral in the image. It isn't related to NGC 4725 as it lies some 200 million light-years away. It is classed as an Sbc? galaxy by Seligman and SA(s)bc HII by NED. Take your pick. The other I mentioned is likely NGC 4747 which is out of the frame to the northeast (upper left). It is also known as Arp 159. My entry for that shows all three galaxies so check it out if you haven't already.

An infrared shot taken by the Spitzer Space Telescope can be seen at:
http://antwrp.gsfc.nasa.gov/apod/ap050901.html
In false color, it shows the area of new star formation as red indicating this galaxy has a single arm though that is hard to see in light our eyes see. Though note the red in the Spitzer image agrees very closely to the blue regions in my image as the massive short-lived blue stars formed in this region of star birth have not yet lived out their short lives. So we see areas of new stars as blue while Spitzer sees them in infrared as red. Though Spitzer is looking at the dust and gas that these stars form out of while I'm seeing the light of the stars that formed out of this dust and gas.

This image is was one of my very early images. I reprocessed it but it needs retaking more correctly.

14" LX200R @ f/10, L=4x10' RGB=1x10', STL-11000XM, Paramount ME

Related Designations for NGC4725

NGC4731

NGC 4731 is a very strange, distorted galaxy on the far side of the Virgo Cluster, about 65 million light-years distant though red shift puts it far closer. It even lies within the borders of the Constellation of Virgo. NED gives it the rather normal classification of SB(s)cd. This gives no hint of its strange, distorted shape. Reminds me of some sea slugs swimming through the ocean. Or maybe some sort of dragon. Others tell me they see a salamander. The NGC project's simpler classification system does indicate it is not ordinary classing it as SBc pec. Most sources attribute its distorted shape to it interacting with nearby NGC 4697 well out of my image to the northwest. Low in my image, however, is NGC 4731A. It too seems strange though most irregular galaxies have a rather messed up shape. NED classes it as Im pec. Could it have been harmed by coming too near NGC 4731? The more I look at it the more I see two small interacting spiral galaxies coming together in a "V" shaped pattern. I can't find any very high resolution images of it but I'm beginning to think it possible this is two galaxies rather than one. Yet another opinion is offered by a paper saying "Interaction. In contact with it to the east, and with each other, are two not dense companions 19 mag." Apparently, this is the "V" shaped structure and the two blue objects to the east (left). I see these two objects as star clouds created from the collision if my interpretation is correct. This needs a lot more study in my opinion.

NGC 4731 was discovered by William Herschel on April 25, 1784. It isn't in either of the Herschel programs.

Even though it is a member of the Virgo Cluster, a region rich in galaxies and far from the dust of our Milky Way, it is just outside of the area covered by the Sloan Digital Sky Survey. This meant little in the way of information for annotating the image. Being at -6 degrees my seeing wasn't all that good when this was taken so I didn't go as deep as usual nor form as sharp an image as I'd have liked. Also, that put it into the belt of geostationary satellites as seen from my latitude, many of which drifted through the frames. It was a pain dealing with all of them as their paths often overlap meaning data rejection stacks don't get rid of them. Also, such stacks remove the asteroids. As there are 5 in the image I didn't want to give up I had to deal with these birds the hard way doing manual data rejection.

Northwest of NGC 4731, in the area above a galaxy at 3.47 billion light-years and below LEDA 3082082 is, what appears to me to be, a distant galaxy cluster though none is listed there in NED.

Details on the 5 asteroids are shown on the annotated image along with the Minor Planet Center's estimate of their brightness.

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

Related Designations for NGC4731