NGC3906

NGC 3906 s an SB(s)d spiral about 54 million light-years distant in Ursa Major about 5 degrees south of far more famous M109. The UGC describes it as: "Eccentric bar. A large number of thin arms." I agree about the eccentric bar but the "thin arms" comment doesn't fit any image I've seen of this galaxy. I also have trouble with it being a d galaxy. That means widely separated arms of which I saw none. Just a disk full of star clusters. The NGC Project simply says SB... for a classification. That makes more sense to me. There is a blue star-like object at the eastern (left) end of the bar the NED considers part of the galaxy though some sources say it is a blue star in our galaxy. I tend to agree it is just a star. The disk of the galaxy is very off center from the bar. This makes it a sloshed galaxy but I found no mention of this odd fact.

The galaxy was discovered by William Herschel on March 9, 1788. Being rather faint it didn't make either of the Herschel 400 observing programs.

It appears to have one companion in the northeastern part of my frame. A rather featureless oval blue blob of a galaxy with little information on it at NED. It's rather hard to classify a blue blob so apparently, that hasn't been attempted. Most catalogs ignore it though it did make the 2MASS and ASK general catalogs.

In preparing the annotated image I came across a bright red star that wasn't there. At first, I thought it might be a new nova. Looking at the POSS plates the star didn't exist. When I checked the Sloan image it was there after all but in the wrong place. I then found a star on the POSS plates not on my image nor Sloan's. Checking that position in SIMBAD I found it was LHS 316, a high proper motion star. It is moving nearly 2" of arc per year. Since the POSS plates are 50 years old it had moved some 1.5 minutes of arc. No wonder I was confused. Fortunately, the Sloan image was recent and it hadn't moved far though was on the "wrong" side of the white star below it. The star is M4.5V so is a red dwarf. Finding it on surveys I find it is some 26 light-years distant so a rather nearby star. Its magnitude is 15.1 in blue light, 13.26 in V (rather close to visual) and 12.3 in red light. It gets far brighter in IR. Since the Sloan image included 3 IR bands it was blood red in their image. I've been making an annual movie of Barnard's star moving through the heavens. Do I now add this one to the list? It is moving only 20% the speed, however. A snail compared to Barnard's star.

There are several galaxies at about 2.2 billion light-years in the image but I found no galaxy cluster or group at that distance. Instead, I found one at 3.29 billion light-years both by photographic redshift and by spectroscopic redshift of its Bright Cluster Galaxy whose position I used to mark the cluster's location. It is listed as having 19 members. No other galaxy with redshift data was at that distance. One nearby was at 3.55 billion light-years but that seems too distant to be a member.

Why all but one of the annotated galaxies are east of NGC 3906 I don't know.

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

Related Designations for NGC3906

NGC3912

NGC 3912 is a peculiar galaxy in northeastern Leo about 96 million light-years distant though non-redshift measurements put it at about 80 million light-years. It was discovered by William Herschel on April 6, 1785 and is in the second Herschel 400 observing program under this designation. It was independently recorded by his son John on March 26, 1827. One or both got the position somewhat wrong and Dreyer didn't catch this giving each an entry in what became the NGC catalog. Thus it is also NGC 3899.

What interested me was two things. First, it is classified as a peculiar galaxy that has a long bar that is very clumpy. It also has two dark clouds of either obscuring dust of maybe just they are areas of few stars. I prefer the dust idea. I found no mention of these in the literature even though they are rather prominent. East of the eastern dark cloud is what is likely a star cloud not related to those in the bar but quite separate. As I'm trying to get all objects in the two Herschel 400 projects I can from my latitude it was an early entry on my to-do list. I'd not seen the lone bright spot nor the dark areas in the survey images I looked at though now that I know they are there they are easily seen. Why they are stronger in my image I don't know as I did nothing different in processing this image as I've been doing now for several years.

Again I had a rather poor night for transparency so I had to limit annotation to objects brighter than magnitude 21.5 rather than my normal 22.9 limit. This cost a lot of distant galaxies that on a typical night would have been easily picked up.

There are a lot of galaxies at about 1.4 billion light-years in the image. This would appear to be a widely scattered cluster. NED indicates there is such a cluster centered just north of NGC 3912 with 13 members and no size estimate. It is MaxBCG J177.50824+26.51845 for those wishing to dig deeper.

Only one quasar candidate is in the image. It seems either there are few if any in an image or it full of quasars or candidate quasars. Arp claimed that quasars were created by active or peculiar galaxies. To him, their redshift was not cosmological but due to their odd properties. He claimed they clustered around such galaxies giving a few examples. But he ignored fields like this one with few such objects around a peculiar galaxy. He even hung on to this idea even after the HST resolved the galaxy the quasar was in proving they were cores of active galaxies rather than objects emitted by closer galaxies. At least several who attended his lectures in his final years said that was often brought up in his lectures and he was holding out for this otherwise long-dead idea.

No asteroids appeared in this image even though I doubled the luminance time to try and make up for the poor transparency this early May night.

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

Related Designations for NGC3912

NGC3917

FGC 1315/UGC 06802 is a flat galaxy in Ursa Major two degrees below Phecda, the southwestern star in the bowl of the Big Dipper. While I'm fascinated by flat galaxies like this one, NGC 3917 is a nice flocculent spiral, a type with many arm segments rather than the full arms of a grand design spiral. So this was a double for me. I centered on the flocculent spiral since it was the more photogenic of the two. By redshift, FGC 1315 is 67 million light-years distant while NGC 3917 is closer at 53 million light-years. Both are further away by Tully Fisher measurements, 74 and 57 million light-years respectively. Either way, they are apparently more than 10 million light-years apart so not related, just in the same line of sight as seen from our galaxy. There are quite a few galaxies scattered around the field. Assuming their redshift distance is correct, FGC 1315 has a diameter of about 45,000 light-years while NGC 3917 is much larger at 75,000 light-years. It is not seen edge on so its flatness can't be determined very well, but appears to me to also have a very small central bulge. In fact, it did make the 2 micron flat galaxy catalog as 2MFGC 09297. This catalog has less strict standards for flatness.

NGC 3917 was discovered by William Herschel on March 17, 1790. It's not in either H400 program.

The annotated image gives the details. Only one quasar is in the image. While a couple of very small galaxies look like short asteroid trails they are just other, likely very distant, edge on galaxies that might have made the Flat Galaxy Catalog if closer so their flatness could be measured. The bulge must be no more than 1/7th the galaxies length to make the catalog.

Lots of red galaxies can be seen in the lower right corner of my image. They are likely members of the galaxy Cluster ABELL 1387, whose center is out of my field of view. It is listed as having 50 to 79 galaxies in a cluster that is 28 minutes of arc across. That's more than the height of my image frame. It is class III which means it has no obvious center with no condensation toward the center. Its distance is listed at about 1.68 billion light-years which is a good fit for the redshift of the few galaxies in the corner of my image with redshift data.

LEDA 2399182 is a very blue compact galaxy between NGC 3917 and the ABELL cluster. Seen on the Sloan Survey image it appears it could be a double core galaxy. Or possibly two very blue round galaxies seen nearly atop one another. At a distance of only 67 million light-years, they are very small with the diameter of the object being only about 4,000 light-years. If two each is likely about 3,000 light-years across. Compact indeed.

This one was taken on about the best night I had last November but winds were running over 40 mph that night. I can work up to about 30 mph but at 40 there's some elongation of the stars. Though oddly it isn't even across the field with sometimes stars right near each other showing different elongation. I am still scratching my head over how that can be. When I get high winds seeing is usually poor. Another oddity is that it was about average this night.

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

Related Designations for NGC3917

NGC3938

NGC 3938 is a very photogenic, face on, many armed, blue spiral galaxy that is often imaged. It was discovered by William Herschel on April 27, 1785. It made my list because it is on the original Herschel 400 list. I take these when nothing on the main list is well positioned, or in this case, seeing wasn't up to the object I wanted to capture. In fact, it was very poor this night. So poor none of the H alpha regions I wanted to capture survived the seeing, especially since I took red when it was lowest and in the worst seeing. I hoped its longer wavelength would help but it didn't. In fact, it is so red starved I couldn't bring it up to even close to blue without creating so much color noise I gave up trying. The core is likely somewhat redder than I show it though it isn't nearly as red as in most galaxies. Another for the proverbial reshoot list that rarely happens.

It is located near the back leg of Ursa Major. Redshift puts it some 48 million light-years away though a single Tully Fisher estimate says 55 million light-years and an estimate using a 2005 type II (not 1A) supernova comes up with 58 million light-years. Flip a three sided coin. I also saw a paper saying 43 million light-years so make that a 4 sided coin. Using the 48 million light-year distance I get a diameter of about 77 million light-years making this a good sized spiral galaxy.

My visual note from April 16, 1985 with my 10" f/5 at up to 150x on a fair but humid night reads: "Large, round, apparently face on galaxy with an even halo. It has a starlike object (core?) but not at its center. Is this an off-center nucleus of just a 14th magnitude field star?" This photo shows it to be the nucleus and the galaxy to be rather unsymmetrically distributed around it leading to my off-center comment.

A couple background galaxies are seen through it, two had redshift data so are marked on the annotated image. There are several galaxy clusters and groups in the image as well. Many have a good spectroscopic redshift for the Bright Cluster Galaxy but only a photographic estimate for the cluster itself. Both are shown with a "p" denoting the photographically determined value. In some cases, there was no redshift for the BCG which is noted with /na. In other cases, it used the same photographic redshift. When that happened I only note the photographic redshift value once (no second value or na). UvES denotes quasar candidates with only photographic redshift estimates. Objects with only coordinates for a designation are noted by type GG for galaxy group, GC for galaxy cluster, G for Galaxy, Q for quasar etc.

The glow about the middle of the far right edge is from a bright star just off the chip. I should have cloned it out.

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

Related Designations for NGC3938

NGC3945

NGC 3945 is a double ring galaxy in Ursa Major just above the bowl of the big dipper. It is about 65 million light-years distant (64 by redshift). It is classed by NED as SB(rs)0+ with a LINER core. The NGC project says more simply SB0. It reminds me of NGC 2859 I posted February 2012. It too has a double ring structure but is seen a bit more face on. I see a small fuzzy blob on the east-northeast outer edge of the outer ring. NED shows nothing at its position. It is seen on the POSS plates so is real. Is it the remains of something NGC 3945 is digesting? I have no idea. A Hubble image of the galaxy's core shows several dust clouds I wasn't able to resolve. An amateur's processing of the HST data can be found at: http://www.flickr.com/photos/77452188@N05/7281940538/lightbox/ . The galaxy lacks a central bulge. At one time it was thought such galaxies didn't have a central supermassive black hole at their core but the HST data says it likely has one, about twice the size of the one in our core though the data is fuzzy enough it could also indicate no black hole but that is of a low probability from how I read the papers. At 65 million light-years the galaxy is about 120 thousand light-years across, about the size of our galaxy if some current papers resizing the Milky Way are correct.

NGC 3945 was discovered by William Herschel on March 19, 1790. It is in the original H400 program. My log for that on the night of April 16, 1985 hurt by humidity at up to 150x says; "Small, round galaxy with a bright inner circle surrounded by a tight halo. Apparently, this halo wasn't seen by the writer's 8" telescope." I'm wondering if I saw the outer halo or just the round disk off the bar.

There are two other NGC galaxies in the image. To capture them I had to put NGC 3945 on the right side of the image. They are NGC 3975 and NGC 3978. They share almost the exact same redshift so are a true pair though NGC 3975 is much smaller. Still, NGC 3975 is rather large at 90 million light-years. So that makes 3978 enormous at over 250,000 light-years measuring the plumes. Just the arms give a size of 190,000 light-years. Still a monster of a spiral galaxy. So where did the plumes come from? I'd think NGC 3975 would be highly distorted if it interacted with it but it looks pretty normal with no sign of plumes. To complicate things NED shows two tiny galaxies against the disk of NGC 3978. If real and in the disk as NED seems to indicate then they could be the remains of its latest meal of dwarf galaxies. That could account for the plumes. Problem is they are right on fragments of spiral arms and appear in my image as nothing more than star clouds similar to several others seen along the arms. So are they galaxies that both happened to align with arms or star clouds in the arms? I feel the latter is most likely but have pointed them out in the annotated image but with the notation G?

NGC 3975 was discovered by Lawrence Parsons, often known as Lord Rosse, on February 21, 1874. NGC 3978 was discovered by William Herschel on March 19, 1790. It isn't in either H400 program.

There are quite a few galaxies in the annotated image at about 135 million light-years. They are likely members of the Abell 1402 cluster centered just below the lower right of my image. NED lists it at a distance of 137.5 million light-years with a radius of 12.5 minutes (about half the vertical size of my image) It is of group class 0 which has 30 to 49 galaxies. Sufficient to take in most of the galaxies at that distance in my image.

In the upper right corner is a very blue object. Some catalogs call it a galaxy, others a galaxy with a very active AGN and still others say it is a blue quasar. Not taking sides I've listed it as G/AGN/Q to cover all three possibilities. Nearby are a trio of three galaxies (lower right of the G/AGN/Q. While NED lists the faintest (upper left of the three) the other two aren't in NED at all so get a question mark for a label. No way to know if they are related or not unfortunately

Several galaxy clusters with a Big Cluster Galaxy at their core are marked in the image, often at a distance that is closer than the anchoring galaxy. Obviously, they both can't be right. While the anchoring galaxy is rather obvious in my image I don't see the other members but I listed the count shown at NED anyway.

The blue blob on the very lower left edge of the image is due to the 8th magnitude, A3 star, SAO 15664 hitting the very edge of the CCD. I probably should have cloned it out but didn't think of that at the time.

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

Related Designations for NGC3945

NGC3953

NGC 3953 and UGC 06840 are a pair of galaxies with the same redshift putting them about 55 to 60 million light-years distant. They are located in Ursa Major about 1 1/3 degrees south of Phecda, the southeastern star in the bowl of the "Big Dipper". NGC 3953 is a beautiful multi-armed, somewhat flocculent barred spiral with a very odd arm structure on the eastern (left) side. Two arms seem to suddenly join and end in a bunch of star clusters. The Sloan image shows the star-like object at the tip as very green. Still, I think it really is a star. Sloan's multiband color filter system can create green stars. I thought this odd arm system might have attracted Arp's attention but apparently not. UGC 06840 in the southwest corner of my image has almost exactly the same redshift but is a very different galaxy. It has a very low surface brightness except for the bar that causes it to be classed as a barred spiral of the Magellanic type. The two galaxies make for a nice contrast.

NGC 3953 was discovered on March 12, 1781 by Pierre Méchain. This discovery was incorrectly applied to NGC 3992 until 2006. Until then its discovery was credited to William Herschel 8 years later on April 12, 1789. This is how it got into the first Herschel program which was developed in about 1984. My log from May 4, 1984 with a 12.5" f/5 scope on a great desert night at up to 150x reads; Similar to M-31 though much smaller. Much arm detail is seen. Very bright nucleus."

There's another low surface brightness galaxy about halfway between them, at least as seen from our galaxy. It is MCG +09-20-023. Unfortunately, I can't find any redshift data for it so I have no idea if it could be related to the first two.

Also in the annotated image are a couple objects identified as being both a quasar and a galaxy. They must show a quasar-like spectrum but certainly are faint for a typical quasar. Normally they are so bright they hide any hint of the galaxy they reside in. These two are dim enough some of the galaxy is visible though my seeing makes that hard to see.

There seems to be a family of galaxies at about 1.1 billion light-years centered on the lower left part of my image. I found no cluster listed for that location though I looked only about 15 minutes beyond the image edge.

As "usual" conditions were poor for this image, especially seeing. Some frames had seeing of 2.75" while others were over 6 though the luminance frames used were no worse than 4". The highly varied seeing caused havoc with color. Some stars in a frame were far worse than others. This created some color flares around stars that might be blue for one and red for another. I did a lot of local deconvolution trying to get the stars to similar sizes but finally gave up. It will be easier to reshoot this one next year. Due to the poorer than normal seeing for the luminance as well I lost a lot of detail that I'd hoped to capture. There's some interesting fine dust detail near the core of NGC 3953 that shows in the best luminance frame but is lost in the other three I used. I took some 25 frames and used the "best" 10 though calling some of them "best" is rather stretching things beyond reason.

This one reminds me of a buzz saw blade slicing through space.

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

Related Designations for NGC3953

NGC3972

SN2011by was discovered by Zhangwei Jin and Xing Gao (China) on 2011/04/26.823. It is in the Ursa Major Galaxy NGC 3972. My awful spring weather prohibited my imaging it until almost exactly a month later on May 26.193 UT. It is a type 1A supernova. These are used a "standard candles" to measure distances to galaxies. In fact, they are responsible for the discovery of "dark energy" that is now causing the expansion of the universe to speed up at an ever increasing rate as its density decreases. To be used for this purpose we must know the distances to nearby galaxies by other means. NED publishes both a redshift determined distance and one by other means. Tully-Fisher in the case of NGC 3972 which is based on the rotational speed of spiral galaxies. I show both distance measurements in the annotated image. Note they are not in good agreement. This may be a case of the supernova improving the distance measurement to a nearby galaxy. I suspect it will have Hubble looking for Cepheid variables in the galaxy to better pin down its distance. Several other NGC galaxies are in the image. The two in the upper left corner have a secondary distance measurement as well but not being spirals it is different. In this case, it is SBF which stands for Surface Brightness Fluctuations. This is based on the idea that the more distant a galaxy of this type the less we can resolve the granular nature of partially resolved stars. The more even the brightness at high resolution the more distant the galaxy. In this case, the two measurements are in good agreement.

I show it at about magnitude 12.7 in my image. Both the star and galaxy should be visible in an 8" scope at a dark site. Not being able to isolate the star against a dark background this is only an estimate as the comparison stars were measured against the dark sky. Also, the star is so bright it went outside the linear response of my chip. I normally use the ST-7 for this type of thing as it is better calibrated and has a much wider linear range. It isn't currently on the scope as its USB cable went bad and until I dismount the telescope and run a new one it is out of service. The SN is rather blue having a blue filter magnitude of 12.8 and a red magnitude of 13.1. So why is the white light measurement even brighter? That's the non-linearity showing up. Without filters, the star is into the non-linear part of the chip's range causing an over bright reading. The filtered stars stayed in the linear range of the chip so are more accurate. Still, due to the background issue, I expect the true brightness to be about a third of a magnitude dimmer than these measurements indicate. Maybe more as current estimates put it between 13.15 and 13.65 that I've seen.

All three NGC galaxies were discovered by William Herschel on April 14, 1789. They aren't in either of the H400 projects.

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

Related Designations for NGC3972

NGC3982

Thanks to having now over 1500 narrow-angle fields in my image library, all covering only about one-fifth of a square degree of sky, I'm now starting to find I can mosaic a current image to a prior one taken years earlier. As it happens this image allowed me to do that. I took this one for the disconnected arm on the galaxy and the 2011 image for a supernova in NGC 3972. I did reprocess this one somewhat as the color balance in 2011 was done differently and wasn't all that accurate as I usually can achieve today.

NGC 3982 is a face on spiral galaxy in the eastern end of the bowl of the Big Dipper asterism. Redshift puts it about 60 million light-years distant while Tully Fisher measurements say 70 million. Assuming the 60 million figure which APOD and a few others agree on it is about 40 million light-years across counting the rather odd arm separated from the rest of the galaxy. Ignore it and the diameter shrinks to just over 30 million light-years which is the diameter often cited for it. NED classifies it as SAB(r)b:;HII Sy2 indicating it has a rather active black hole feeding at its core. The NGC Project omits reference to the ring. A note at NED talking about the HST image of the galaxy looking for pre-supernova stars says: "Although this galaxy was classified as ringed in the RC3 catalog, in our Hubble images this feature is clearly identified as a spiral of star-forming regions, star clusters, and dust lanes." No, they don't know which star will blow, only they hope when one does it is captured in the data for further study.
The HST image is at: http://hubblesite.org/newscenter/archive/releases/2010/36/image/a/

The galaxy was discovered by William Herschel on April 14, 1789 and is in the original Herschel 400 observing program. My notes from April 16, 1985 at 150x with my 10" f/5 under humid skies that limited transparency reads: "Round, featureless puff of a galaxy, somewhat brighter toward the west edge. I didn't see the nucleus as the writer mentions though did see the illusion of one at 50x that vanished at 150x. Three other galaxies are in the same field, NGC 3398, 3972 and an unplotted one." I was using the Skelnate Pleso Coeli Atlas at the time which didn't go all that faint for galaxies or anything else.

Also in the field are a few interesting objects. ASK 238991.0 to the east looks sloshed with its core displaced to the southwest. A rather red quasar at 11.64 billion light-years (z=3.100774) is to its north. With its light stretched to over 4 times its original wavelength that might explain the reddish color along with dust and gas between us. To the southeast of NGC 3982 is a triple galaxy at 850 million light-years with a 4th one that's nearly twice as far away getting into the group. Oddly it is nearly twice the size of the much closer trio. That means it is much larger than the others. I measure it at just over 200,000 light-years in size. while the largest of the three is 70,000 light-years across. The distances to the galaxies in the field seem to group with one at 700 million light-years, another at 850 million another at 1.05 billion etc. I didn't find any names for these groups other than those noted in the annotated image.

In processing the image which was taken over several months, just finishing in January and in which I'd remounted the camera between images resulting in the need to crop this image a bit, I noticed a glow at the northern edge. That was NGC 3972 mentioned in my notes. I had taken that galaxy, along with NGC 3998 back in May of 2011. I have combined the two into a mosaic. NGC 3998 is the large elliptical in the upper left corner and is also in the original Herschel observing program. My notes on it the same night as 3982 reads: "Largest and brightest of the 4 galaxies in the field. It has a bright nucleus with a round halo. An unplotted galaxy (3990) is just west of it. NGC 3982 and the very difficult NGC 3972 are also in the same field." Apparently, I never saw NGC 3977 to the north of NGC 3972. Its core seems no harder to see in my image than 3972 but I missed it. I've never revisited the field visually.

My reason for taking NGC 3972 was that supernova 2011by had just been seen in it. That is the bright blue star on the north edge of the galaxy above the core.

Note the SN in 2011 was 2011by while at the same time of the year in 2016 A third letter is needed. The letters work the same as our decimal number system but with each column 26 times larger not 10 times. So 2016bkv I posted in April was #484 in 2016 while 2011by was only the 50th of 2011. The survey cameras are making a huge difference!

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

Related Designations for NGC3982

NGC3997

NGC 3997 is a galaxy that's part of a large group that goes by many names. The NGC Project uses the name NGC 4007 Group which has its own baggage I'll get to later. The group is located in Leo just over the border with Coma Berenices and lies some 220 million light-years away.

NGC 3997 is a rather confusing galaxy. Its structure is very disjointed with plumes everywhere. One arm appears could be considered a separate galaxy if the rest of NGC 3997 is masked out. The annotated image hints at the confusion. The main core is listed as NGC 3997 but only .24 arc seconds away is NGC 3997 NED01. Since it is only a quarter of a pixel away I didn't note it. Nor could I see anything on the Sloan image. Yet NGC 3997 is listed at magnitude 14.02 and 1.7 by 0.6 minutes while NED 01 is 1.63 by 1.23 minutes at magnitude 15 and listed as I pec. To me, this fits the area better than does the description of NGC 3997.

North of the core is a second somewhat blue object. It's not in NED but the small area between it and the core is listed as SDSS J115748.21+251618.1 a separate galaxy. It is listed as star-like 0.08" and magnitude 18.5 yet nothing like that is seen on the Sloan image that I could see. The size is much too small for any feature on the Sloan image in fact.

If that wasn't confusing enough between the odd arm that could be taken for an edge on disk galaxy and the core is where NED puts NGC 3997 NED02. I see nothing at that position yet NED sees a galaxy measuring 1.97 by 0.67 minutes. Just the size of that odd feature that could be taken for an edge on galaxy. Just the position is wrong. Then I noticed NED gives the error circle as 5". That is sufficient to just include it. The annotated image points to the center of the error circle but I do think they mean that object that appears to be an edge on galaxy. No redshift is given, however. It is classed as simply pec for peculiar. NGC 3997 itself is listed as SBb pec. Also at about its position, well 9" away, is 2MASXI J1157489+251615, an IR galaxy. It is listed as .9 by .4 minutes and magnitude 18.1. The position is closer to the apparent edge on galaxy (arm) than the core but not exactly. Yet it shows only a 0.5" error circle, the minimum NED normally uses. I didn't put it on the annotated image as things were getting a bit crowded. Go up two pixels from the end of the NED02 line and left 2 pixels for its position. The 2MASS catalog calls it a low surface brightness galaxy. Another piece that looks like it could be a separate galaxy is the blue object under the core. NED shows nothing at or around its position but for the objects already mentioned. After this, my head was spinning and I didn't dig deeper. I probably should have. In any case, NGC 3997 looks to me to be the result of a likely merger with another galaxy or a merger in progress with all its disjointed arms and plumes. It was discovered by John Herschel on February 23, 1832.

Now for some of the other NGC galaxies in the field. At least they aren't all confusing but there are issues with some of them as well. So hang on for a sometimes bumpy ride.

NGC 3987 is a classic edge on spiral classed as Sb by all at magnitude 13.9. But note the bright, star-like object in the dust lane right of its core. This is LEDA 4547376. But suddenly this nice simple picture gets bumpy because NED says this star-like object is really 1.44 by 0.32 minutes in size at magnitude 16. I can't see this in the Sloan image however. I just see a small round object. It was discovered by William Herschel on April 6, 1785. It's not in either H400 program.

NGC 3989 is a small spiral classed as S?, Sbc and Sb depending on the source. It is magnitude 15.6 It was discovered by R.J. Mitchel on April 27, 1854.

NGC 3993 is another edge on spiral classed as Sb or S.. depending on the source. It shines at magnitude 14.2 William Herschel found it on April 6, 1864. It isn't in either H400 program.

NGC 3999 is an SO galaxy of magnitude 15.7. No redshift is provided. This one has some interesting information at the NGC Project about its identity. "This entry is one of several galaxies discovered at Birr Castle in the N4005 cluster. According to the 25 April 1878 discovery note, the position with respect to the mag 8 star (SAO 82077) is 277" in PA 201.3? (SSW). At this exact offset is a faint galaxy, CGCG 127-117, at 11 57 56.5 +25 04 05 (2000) and CGCG identifies this galaxy as N3999. The RNGC position (and identification?) is clearly in error being 0.4 min of RA too far E and 4' N. The 1975 coordinates should read 11 56.7 +25 13. Listed in RNGC Corrections #3. This galaxy is not in MCG or RC3 and was not found by Bigourdan. - by Steve Gottlieb" It's discovery is credited to the Earl of Rosse himself.

NGC 4000 is an, Sc, S? or Sbc depending on the source, galaxy seen pretty much edge on. It is magnitude 15.5 The good Earl of Rosse found this one April 25, 1878 as well.

NGC 4005/NGC 4007 is one of those NGC galaxies with multiple numbers. It is classed as S?, Sb and S.. and shines at magnitude 13.9. As to the two numbers the NGC Project has this to say. "N4007 was discovered by WH (III 325) but was reduced incorrectly and the North Polar Distance in GC and NGC is two degrees too far south (the offset is 45' south of 4 Comae). This error was caught and corrected by Dreyer in Scientific Papers of William Herschel. Struve and Rosse (object Alpha on the sketch of the cluster) later rediscovered it, so it received the second NGC number N4005, this time at the correct place.

"All major catalogs identify this galaxy as N4005 although you could argue that by prior discovery, III 325 = N4007 should take historical precedence. In any case, it is clear that N4005 = N4007. Unfortunately, because of the two degree error, the NGC position falls close to N4003. So, Reinmuth (Die Herschel-Nebel), Carlson's NGC/IC Correction list, CGCG, UGC, MCG all equate N4007 with N4003 ignoring Dreyer's correction. See Catalogue Corrections, Malcolm Thomson and NGCBUGS. - by Steve Gottlieb" It too is a William Herschel discovery on April 6, 1785. It's not in either H400 program.

NGC 4015 is a double galaxy. NED01 is a nice elliptical (rare in this group) of magnitude 13.8 while its companion with nearly the same redshift is a near edge on classed S? and shines at magnitude 12.81. There is a dark dust cloud seen over the elliptical. Since dust is exceedingly rare in such galaxies could it come from the edge on companion? Or is the alignment with that galaxy just a coincidence? It was found by John Dreyer on April 26, 1878.

NGC 4018 is another near edge on galaxy. They seem unusually common in this group! It is listed as being Sab by all sources I checked and is magnitude 14.7. We end the NGC list with one everyone agrees about. Sure wish that was the rule rather than the exception with this bunch! It too was found by John Dreyer on April 26, 1878. Note this is the John Dreyer that compiled what became the NGC and IC catalogs.

I've indicated other members of the group by name in the annotated image. If I thought their angular size indicated they were a member but no redshift data was available to confirm this I listed the name followed by a question mark.

While many galaxy clusters were listed for the field only two could be marked with an obvious core galaxy. One is southeast of the center of my image. It is MaxBCG J179.54663+25.05842. Its core galaxy is very obvious with some detail in my image. Its distance is only 1.8 billion light-years and contains 15 members in an unspecified radius. The BCG is also listed in the 2MASS catalog of IR sources so may still be feeding. At least it is full of dust being heated by unseen newly minted stars. The other cluster is on the far western edge of my image. It is GMBCG J179.11209+25.16277. It is listed as having 11 members. It BCG also is in the 2Mass catalog as an IR source. In the case of the first cluster, there was no redshift value for the BCG. For this cluster there is but it differs from that of the cluster itself. The cluster is listed at 3.4 billion light-years and the galaxy at 3.2 billion light-years. The galaxy's redshift is by spectroscopic measurement while the cluster is photographic. So I expect the 3.2 billion light-year figure is the one to use here.

The NGC 4005/7 group extends well beyond my field of view. Those with wider fields will pick up far more than I have so this is a good group target for small systems. I'd like to see what you get. Under dark skies, it should be quite spectacular.

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

Related Designations for NGC3997

NGC4004

NGC 4004 is one of the strangest galaxies I've imaged that didn't make it into Arp's Atlas of Peculiar Galaxies though it certainly appears more peculiar than dozens that are in the Atlas. It is located in the far northwest corner of Leo, right beside Coma Berenices and Ursa Major boundaries. Redshift puts it about 170 million light-years distant. It is likely a member of the ZwCl 1154.9+2806 galaxy cluster which is some 70 minutes of arc in diameter with 209 members according to NED. It is also known as the UGCl 243 galaxy cluster. It is also part of the NGC 4008 galaxy group of 14 galaxies. NED shows the group's distance at 170 million light-years but the distance to NGC 4008 itself (out of my image to the north) as 180 million light-years. No size is listed for the group.

NED classifies it simply as peculiar and notes it is a Narrow Emission Line Galaxy which would indicate a lot of star formation is going on, likely within the small, bright "s" shaped region around the core and the many star forming regions (blue) seen in its tidally distorted arms. The NGC project classifies it as Irregular another source says "disrupted?". There seems little agreement on this one other than it is very strange indeed. I was surprised to find so little on this highly unusual appearing galaxy. What little I did find seems to indicate it is thought to be the product of a galactic merger. One very old paper (1959) said; "Possibly two Sc (theta?) in contact and an E." indicating they saw three galaxies superimposed. Shows the state of photography back then as it certainly appears as one highly disturbed galaxy in today's images. I see no obvious second core so the merger appears rather complete though it has left the structure of the galaxy highly disturbed. It was discovered by William Herschel on April 11, 1785.

Nearby is NGC 4004B which may be IC 2982. NED says this IC identification is "highly uncertain". SIMBAD has no such qualification. The other NGC galaxy in the image is NGC 3998 a compact elliptical galaxy so rather featureless. It was discovered by John Herschel on April 13, 1831. How his dad missed it is unknown. It was bright enough but rather star-like so he may have not recorded it thinking it a star. Only a guess on my part. It could be it was just outside his scan as his field of view was quite small compared to what modern telescopes can deliver for their focal length.

Arp thought there was significance to quasars being found around peculiar galaxies and came up with the idea that they were nearby objects ejected from these peculiar galaxies with the redshift being due to a factor other than cosmological distance. With many with widely varying redshifts this field should have been interesting to him but I can't find that he knew about it.

The field seems to contain another group of galaxies at twice the distance of NGC 4004, about 380 million light-years. Searching NED for a cluster at this distance within a degree of NGC 4004 came up empty.

The field is full of distant faint fuzzies, nearly all of which have no redshift data. The couple that did are shown on the annotated image.

NGC 4004 seems to remind my strange brain of the "Mark of (a dyslectic) Zoro" as it is a mirror image of a "Z" and unsymmetrical as well.

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

Related Designations for NGC4004