NGC4571

NGC 4571 is a face on low surface brightness galaxy in the Virgo Cluster a half degree southeast of M91. Thus, while a member of the Virgo Cluster it is located in southern Coma Berenices. It has low contrast blue arms on a mostly featureless reddish disk with a small rather bright core. One paper says it has an arm structure similar to M101. I really pushed the contrast and color saturation to bring out these very low contrast arms. Its distance is only 31 million light-years by redshift which is undoubtedly too close. Virgo Cluster galaxies have rather high velocities that make redshift an unreliable distance indicator. Tully-Fisher measurements show a distance of about 50 million light-years which is much more reasonable but likely still too close. I'm finding most current sources are saying about 60 million light-years for its distance which is pretty much the accepted distance to the Virgo cluster itself. Using 60 million light-years for its distance I get a size of 72,000 light-years. It was discovered by William Herschel on 4571. John Herschel thought it might be M91 which led to years of confusion before NGC 4548 was settled on as Messier's M91. On November 23, 1900, Arnold Schwassmann came across the galaxy. For reasons I haven't been able to discover Dreyer treated it as a new object giving it the designation IC 3588. Was the confusion over M91 to blame? I can't find the answer but tend to doubt it.

To the northeast is Malin 1 and Malin 1B. A note at NED says: "This galaxy (Malin 1B) has previously been given a stellar classification owing to its round shape. The high resolution of WFPC2, however, enabled us to view the galaxy's faint disk and thereby determine its true nature as a galaxy." In my data, it doesn't have a PSF of a star though is close. Still, even by eye, I didn't think it a star so find this note rather puzzling. That brings up Malin 1 itself which is listed as being a GLSBG which stands for Giant Low Surface Brightness Galaxy. Its core certainly isn't unusually faint but its disk is in relation to the core. I measure it at about 100,000 light-years in size. I'm not sure how that makes it a giant. Maybe I'm not seeing its full extent though I do see the same size as the SDSS image. Turns out neither I nor SLOAN is seeing it's true size. See http://www.slate.com/blogs/bad_astronomy/2016/02/04/malin_1_is_the_biggest_spiral_galaxy_known.html for the story and a very deep image.

Another puzzle is PGC 042178 to the northeast. It is blue shifted so I list its distance as n/a. It is classified as dE4,N which is a dwarf elliptical with a nucleus. It does have a blue starlike object west of its center. Looking at its PSF in my data it is a star. Sloan image also makes it appear to be a star. If it is a foreground star then where's the nucleus? Another blue shifted dwarf elliptical, PGC 042193 is seen near the eastern edge of my image. It has no nucleus though is a bit brighter if you ignore the star-like object in the former galaxy. Are they related, are they in the Virgo Cluster? I found no answers.

An amateur processed image of NGC 4571 in pseudo color by the HST in green and near IR light can be seen at https://www.flickr.com/photos/77452188@N05/7176855420/

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

Related Designations for NGC4571

NGC4605

NGC 4605 is considered a member of the M81 group though it resides about 18.25 degrees east of M81 above the handle of the Big Dipper. It is a SBc dwarf spiral galaxy about 28,000 light-years across and 16 million light-years distant, somewhat further than M81. I'm afraid I can't see much hint of spiral structure other than it being a disk galaxy and no hint of a bar or even a core. I'm assuming the star like object at its center is just a field star in our galaxy. Though it's position is less than one second of arc different than that NED has for the galaxies center. I couldn't find anything to decide this issue. Visual observations speak of a star within a half degree of its center that's 13th magnitude. It was discovered by William Herschel on March 19, 1790 and is in the second Herschel 400 observing list. It's surface is strangely two tone either bright or dim with little variation, especially of the brighter star clouds. No matter how I processed it it came out this rather bi-toned galaxy. I assume this is due to the very poor conditions the night I took the data. I should have tried on a better night but this is late May and I can only get one per night so didn't want to waste the night on the chance I might get better data.

For a lot more on this galaxy plus a great HST image, south up, of it see: http://www.spacetelescope.org/images/potw1418a/
http://www.nasa.gov/content/goddard/hubble-eyes-a-scale-of-the-universe/#.VIdff8l8qM1

There's an obvious, likely background, galaxy just above the southeast end of NGC 4605. Strangely it is listed only as the IR source 2MASXi J1240129+613609. There's no indication it is a galaxy but the positions match. It isn't listed by NED as being in the Sloan data. I've seen this with blue galaxies but this is a rather red one and they have always been seen, until now that is.

NED shows a quasar candidate near one edge that I've marked in the annotated image that lies far beyond the galaxy if the photometric redshift is correct. in fact the image contains a record number of quasars and candidate quasars, most identified as UvES, some by CQ (candidate quasar rather than calling any amateur radio operator), in the annotated image. 19 of them if I counted correctly. One of them is a puzzle. Toward the upper left is the galaxy CGCG 293-033 and to its lower left is a double object, a blue galaxy on the east and a blue starlike point on the west. NED identifies the starlike point as a star giving its distance as 9.52 billion light-years. Yet also says it is a candidate quasar. Then it identifies the galaxy as a verified quasar yet nearly all catalogs say it is a galaxy. It certainly looks like a galaxy both in my image and the much clearer Sloan image of this pair of objects. So that's how I have identified it in the annotated image.

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

Related Designations for NGC4605

NGC4631

ARP 281/NGC 4631-4627 is the first of 6 entries under his category for infall and attraction. The two NGC galaxies that make up Arp 281 are in the process of merging and are gravitationally bound. Nearby NGC 4656 is also gravitationally bound to this system and likely interacted with it hundreds of million years ago by most accounts. The system is likely about 25 million light-years distant though I found no good consensus on its distance. Redshift, unreliable this close, says 40 million light-years. Tip of the red branch estimates at NED show a distance of about 25 million light-years while Tully fisher measurements show a closer distance of about 16 million light-years. Some papers say 30 million. Non redshift measurements of NGC 4627 gives a distance of 30 million light-years compared to 19 million for all for NGC 4631. Balancing these and others I decided on 25 million light-years which gives a size of NGC 4631 of about 116,0000 light-years. Some sources say it is a starburst galaxy but NED didn't note this in its classification. Still it seems quite likely after its interaction with two other NGC galaxies. NGC 4627 is 17,000 light-years in size including its plumes using the same distance.

The pair was discovered by William Herschel on March 20, 1787. NGC 4631 is in the original Herschel 400 observing program. My comments using a 12.5" f/6 scope at up to 150x on an excellent night in the New Mexico on April 27, 1984 desert reads: "WOW! edge on with many faint knots but no dust lane, Round companion appears larger than in photos but maybe I'm not seeing the full length with NGC 4631. In same low power field with NGC 4656." Arp's comment: "Knots resolved with 48-inch. Diffuse counter tail on companion."

NGC 4631 is often called the Whale Galaxy though I've also heard it called the submarine galaxy. The annotated image lists all galaxies that NED had redshift data on.

Arp's image: http://ned.ipac.caltech.edu/level5/Arp/Figures/big_arp281.jpeg

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

Related Designations for NGC4631

NGC4633

NGC 4633 is a strange disk galaxy possibly interacting with NGC 4634. The pair are located in southern Coma Berenices. Their distance is difficult to determine. By redshift, both are about 28 million light-years distant. Only NGC 4633 has a non-redshift measurement that comes in at 69 million light-years. Quite a difference. If they are interacting then NGC 4634 could also be about 69 million light-years distant. While I can't find an HST image of NGC 4633 there is one for NGC 4634. https://www.spacetelescope.org/images/potw1238a/ The text puts it at "about 70 million light-years". The pair are members of the Virgo Cluster though are on the outskirts of it as most spirals are. Radial velocities of Virgo Cluster members vary drastically with some even blue shifted indicating high orbital velocities are common in the cluster. Thus it isn't unusual that redshift gives erroneous values. Using 69 million light-years I get a size for NGC 4633 of 50,000 light-years and 71,000 for NGC 4634.

Both appear distorted by their interaction. NGC 4633 is classified at NED as SAB(s)dm: while Seligman says SBd?. The NGC Project leaves off the question mark. I classify it as "A Mess" though that isn't a valid classification. Still, it describes it better to my eye. Likely it was a much better organized barred spiral before it had a run-in with NGC 4634. Seen edge-on NGC 4634 seems to be a somewhat ordinary edge on galaxy within an oddly unsymmetric halo. In some ways, it resembles the Hamberger Galaxy, NGC 3628. Though its dust lane is also far from symmetric extending beyond the disk and into the halo to the northwest and breaking up and disappearing before reaching the southeast end of the inner galaxy. The HST image doesn't go deep enough to show much of the halo, unfortunately. Also, its color filters result in a somewhat false-color image missing the reddish hues that extend into the halo. Most halos are filled with new hot stars so tend to be blue but this one had a lot of cooler stars in it for some reason. Note I did push color on these two galaxies more than usual to bring out this oddity.

NGC 4633 was discovered by Edward Swift on April 27, 1887 and entered into the NGC catalog. Later on November 23, 1900, it was discovered by Arnold Schwassmann. Due to apparently different coordinates and Dryer not realizing it was a duplicate was entered into the IC catalog as IC 3688. NGC 4634 was discovered by William Herschel on January 14, 1787 but is not in either of the H400 observing programs. A Sloan image of this pair can be found at: http://skyservice.pha.jhu.edu/DR9/ImgCutout/getjpeg.aspx?ra=190.668663&dec=14.2988&scale=0.8&width=800&height=800&opt=&query=

NED shows a 20.1 magnitude quasar seen through NEG 4634. I point to its location though it is lost in the glare of the galaxy in my image. I can't even find it in the HST image linked to above. There are three asteroid trails in the image. One ran right over the 20.2 magnitude galaxy, SDSS J124212.15+142124.3. NED has no distance data for it. Just east of NGC 4634 is a pair of galaxies that have the same redshift so may be interacting. The red one, PGC 042739 is shown at NED as being BCD?. BCD normally stands for Blue Compact Dwarf. But given its color and distance is neither blue nor a dwarf. At least they added a question mark. It may be it got this designation before redshift was measured. Still, it is obviously quite red compared to its blue companion which should have been quite evident since the mid 50's when the first POSS survey was done in blue and red light. If there's another meaning for BCD I have never heard of it. https://ned.ipac.caltech.edu/level5/Sept02/Palco_BCD/Agpaz3.html

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

Related Designations for NGC4633

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