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

NGC4013

NGC 4013 is a rather bright edge-on spiral galaxy in Ursa major just over the western border of Canes Venatici. At 55 million light years it is rather close but also smaller than some other famous edge-on galaxies like NGC 4565 which is on my redo list if the weather ever cooperates. Edit: Never retaken as yet. In the meantime, this one will have to do. It was discovered by William Hershel on February 6, 1788. It is in the second H400 observing program.

Hubble took a rather famous shot of this galaxy back in 2001 so I'll just refer you to the text with that image. http://hubblesite.org/image/1022/news_release/2001-07 Note the Hubble image is "upside down" compared to mine. I have north up while they show it with south up. The Hubble camera can't see the entire galaxy at once so imaged what is the right half of it in my image.

Edit: This is an early image with all the processing problems I had with insufficient software back then. Also, my imaging technique wasn't all that great at that time either.

14" LX200R @ f/10, L=4x10'x2 RGB=2x10'x3, STL-11000XM, Paramount ME

Related Designations for NGC4013

NGC4026

This field attracted me as a study in the contrast between a high surface brightness galaxy and a very low surface brightness galaxy. Both are about 50 million light-years distant and are found in Ursa Major about a degree northwest of more famous Arp 18 (NGC 4088). They are considered members of the M109 galaxy group. NGC 4026 is an edge on S0 galaxy. Note that the intensity of the disk drops away from the core then brightens again before fading normally. This bright region may indicate a ring if seen face on. Is the ring due to dust hiding the inner parts of the disk or just a higher star population? Papers I saw disagree. A radio-based paper said it found no dust. Visual observations find dust. Maybe it is both. Certainly, I can't answer this from my image. Interestingly, older papers see this one as a hidden Sa spiral but newer ones all say S0. HI radio observations show an HI tail heading south from the galaxy. Its cause seems unknown as far as I could find. Did nearby DDO 102 have anything do do with this? I rather doubt it as its mass seems quite low but it may be dense with unseen dark matter and thus be able to cause a plume in NGC 4026. Some very low surface brightness galaxies have a lot more dark matter than their brightness would indicate though most don't seem to have enough to cause this plume. At least not to my way of thinking. Also, it doesn't point to DDO 102. It may be due to something it ate long ago. I found no paper trying to explain it, I'm just reporting it exists.

NGC 4026 was discovered by William Herschel on April 12, 1789. It is in the original H400 program. My notes from that on April 27, 1984 with my a 12.5" f/5 at 150x under excellent conditions reads "Starlike nucleus in what looks to be an edge on but is classed E8-S0 in Burnham's. No dust lane seen which agrees with the latter classification. Seems 12th magnitude or a bit brighter." A paper was written since my observation rule out it being an elliptical galaxy. I don't see that starlike nucleus mentioned in my notes but assume that has to do with the stretch I used to bring out DDO 102.

The low surface brightness galaxy is DDO 102 in the David Dunham Observatory's catalog of low surface brightness spiral galaxies. it is also known as UGC 6956 and PGC 37682 among other designations. The core is rather faint and its arms very faint. Unfortunately, I wasn't able to find much on it or why it is so low luminosity. I assume star formation is weak yet the arms are surprising blue compared to the central bar region. I see no real core just the bar with some star clouds in it. The arm structure is ill-defined. This may be due to it being barely above my noise level. I couldn't find any deep images of this that showed any more than my image.

Assuming a distance of 50 million light-years I measure NGC 4026 at about 66,000 light-years across. DDO 102 is a bit harder to define but my best estimate is about 37,000 light-years.

After constant complaining about how bad the nights have been this one was taken on a better than average night, at least better than I've had in some time. The annotated image shows a galaxy near the top NED lists at magnitude 22.9. It's barely visible. Still, this and the seeing is well above the norm for the last few years. While taken the same night as IC 320 and NGC 0644 conditions went bad after NGC 644 then cleared with much better seeing and transparency for this image near dawn. I'd have taken more data but dawn ended the night and the following nights were much worse. I did take two extra blue frames due to the faint arms of DDO 102 but in dawn skies. While I used them I don't think they helped significantly.

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

Related Designations for NGC4026

NGC4038

Arp 244/NGC4038-9 are almost too low for my scope to see. Certainly too low to see clearly being below my normal 15 degree south limit. But they are so interesting I had to try anyway. These are known as the Antenna, clamshell or Ring Tail Galaxies. NGC 4038 and 4039 are a much pictured pair of colliding galaxies. Massive star birth has been triggered by the collision and huge tidal arms (the antennae) pulled out of them. When galaxies collide the dust and gas do collide but the stars do not. They are just far too small and too far apart for that to happen. But the gravity field is so strong that it can tear stars out of the galaxies and throw them across the universe as seen in the two tails of these galaxies. If your monitor can see into the darkness well enough you can see the lower (longer tail) actually starts to curve back on itself. These two are thought to be about 65 million light years away in the constellation of Corvus. The Hubble telescope took this photo of the upper galaxy in my shot (NGC 4039). http://imgsrc.hubblesite.org/hu/db/1997/34/images/d/formats/full_jpg.jpg and http://cseligman.com/text/atlas/ngc4038noao.jpg
Hubble can resolve individual stars in a galaxy at this distance thanks to not having to look through our atmosphere.

Due to clouds I had very limited color data which shows up as rather blotchy color. Two asteroids decided to wander through my view
Upper left: (15297) 1992 CF Mag 16.4
Lower left: (54283) 2000 JG48 Mag 17.2

The "stars" you see in the galaxies are really huge clusters of super massive stars created by the collision. Some are still shrouded in their Hydrogen and dust cloud from which they formed. The hydrogen glowing its characteristic pink-red color. Others have completely used up the hydrogen and glow blue though some hydrogen emission can be seen on their edges. Note I've pushed the color to extremes here to show these features. The true colors would be much more muted if your eyes could actually see them. Which they never could from any vantage point as they would be just too faint.

The Galaxies were discovered by William Herschel on February 7, 1785 and is in the original Herschel 400 observing program. My notes from that made on April 16, 1985 using my 10" f/5 at 50x hampered by how low it was even in Nebraska and the extinction from high humidity reads "Large, fairly easy object, mottled a little brighter toward the center. This was limited to NGC 4038 as 4039 wasn't in the program. I didn't see the tails."

This was taken back early 2007 when my imaging techniques were poor. It is severely photon starved. I've had it on the redo list for years but conditions just haven't made this possible. Until then this will have to do.

14" LX 200R @ f/10, L=6x5' RGB=1x5', STL-11000XM, Paramount ME

Related Designations for NGC4038

NGC4051

NGC 4051 is a very well studied spiral in Ursa Major only some 43 to 46 million light-years away. It is considered midway between a true spiral and a barred spiral by some sources. It is one of 6 galaxies Carl Seyfert studied in 1943 that later became classic Seyfert Galaxies. While most sources consider it a Seyfert 1 galaxy I find papers say it is 1.25, 1.5 and 1.8 among other definitions. The Seyfert classification can be considered a quasar that is no longer active enough to meet that definition but still has an active supermassive black hole. It is considered one of the least luminous core Seyfert's known. While the Seyfert designation refers to the activity of the black hole at its center I was pleasantly surprised at how many HII regions popped out in my simple LRGB image without the need to use any H alpha light to bring them out. One region, however, appears white. This caused many galaxy catalogs to pick it up as a galaxy. It is noted as ASK 318879.0 in the annotated image but has many other galaxy designations. Still, NED says it is an HII region, not a galaxy and its redshift is similar to that of NGC 4051. On the other hand ASK 318868.0 in the southern part of the galaxy appears to be a true galaxy at 72 million light-years.

I put NGC 4051 on my list because many sources call it a 3 armed spiral which was one of Arp's classifications for his Atlas of Peculiar Galaxies. One source calls it 4 armed. But to me, these extra arms appear more like arm segments and a split arm (which was another Arp category). NED lists 48 different designations for this galaxy, a good indication of how well studied it is.

This one was discovered by William Herschel on February 6, 1788. It is in the original H400 program. My note from that with my 10" f/5 on April 20, 1985 on a humidity hurt night at 100x says, "Large oval halo coming off of a highly elongated central core. Might be a barred spiral? Large diffuse halo, best seen with averted vision."

The annotated image lists all objects NED had a redshift value for but for one galaxy cluster with very vague coordinates and nothing obvious showing in the area that I could use to point to it.

I ran into a very unique processing issue with this one. The red data was taken on a night of very poor seeing. So poor I gave up and took the other colors a different night. The luminance, however, was taken on a rather good night. When I went to process the color data I found the seeing during the red image had moved the stars every which way compared to their position on the blue and green images. Not only were they larger on the red image some were west of their true position, others east, north or south etc. This resulted in some very mismatched stars that even RegiStar couldn't handle. You will see various red and blue sides to stars at rather random distribution though in any one small area all seem off in one direction just at different amounts. I "fixed" the most serious of these but it would have taken all year to fix them all individually. Oddly this didn't seem to bother the galaxy itself. Maybe next spring I'll redo the color data to fix this issue. (Edit: So far it hasn't happened) For now, I have to remember that while I can take color data on poorer nights than luminance there is a limit to how far I can take that and get a usable image.

14" LX200R @ f/10, L=7x10' RGB=3x10', STL-11000XM, Paramount ME

Related Designations for NGC4051

NGC4068

NGC 4068 is an irregular starburst galaxy in Ursa Major. It is thought to be at the end of its starburst phase. NED classes it as IrrAm while the NGC project just says Irr. Redshift says it is about 18 million light-years away but other measurements put it closer with 13 to 14 million light-years being the currently accepted figure that I was able to find. I've shown both on the annotated image. The HST took an image of part of it as part of a three galaxy series of dwarf irregular starburst galaxies; NGC 4068, NGC 4163 and IC 4662. I've imaged the first two. The IC galaxy is only visible from southern skies so always far below my horizon. The HST article is at: http://hubblesite.org/newscenter/archive/releases/2009/19/ Only part of the galaxy fits its limited field of view. You can read all about it at that site which saves me a lot of typing.

Below and left of NGC 4068 is SDSS J120431.81+522749.0. It is listed in the 2MASS catalog of IR sources. It looks rather peculiar. All NED says about it is that it has an AGN at its core. While this doesn't necessarily mean it is the result of interaction it appears that it is a likely merger candidate with the very odd arm structure and plumes. The northern plume is rather bright but the southern needed a lot more time to bring out as it is just visible in my image. I'd love to see what Hubble would see looking at this one. At over a billion light-years it is a rather big galaxy. From the end to end of the plumes it is about 70 arc seconds in size. At its distance of 1.089 billion light-years that would be a diameter of 370,000 light-years! It appears to be somewhat tilted to our line of sight.

South of NGC 4068 is the galaxy cluster GMBCG J180.99631+52.47507 which contains only 8 members in an unknown area according to NED. Its position is also that of the Bright Cluster Galaxy (BCG) that anchors the cluster.

Further south is the core of Abell 1457. NED lists it as a galaxy cluster of richness class 0 and a distance of 840 million light-years. Richness class 0 means 30 to 49 galaxies. No diameter is given for the cluster. Galaxies of this distance are scattered across the image so apparently, it is quite large considering the core is near the south edge of the image. I centered the label over the listed center of the cluster.

To the west (right) of NGC 4068 is the galaxy cluster GMBCG J180.73018+52.62528 at 4.2 billion light-years. It's BCG has the same position. The cluster is listed as having 13 members. Again, no size is listed. In this case, I do see what appears to be several members in the area. I had to put the label to the left so as not hide some possible faint members.

To the northeast edge of the image is the galaxy cluster WHL J120503.3+524355 at 3.1 billion light-years though its BCG has the exact same coordinates it is listed at 3.2 billion light-years. Why I don't know. The cluster is listed as having 15 members. As usual, no diameter is given

The galaxy cluster in the bottom left corner is GMBCG J181.46298+52.46936 at 3.1 billion light-years. In this case, the BCG has the same position and nearly but not exactly the same redshift. The difference is in the next decimal point and insignificant compared to measurement errors but I do find it odd when they differ.

Even closer to the southeast corner is WHL J120559.1+522915 at 3.2 billion light-years. While there appears to be a BCG at the exact coordinates of the cluster it isn't listed in NED. NED only lists the cluster which it says has 30 members in an unknown area. Though within one second of arc of the cluster position is the 20th magnitude galaxy, SDSS J120559.05+522915.9. Since the cluster's position is listed with an uncertainty of 1.5" but the galaxy's position is listed to an accuracy of 0.5" the two positions likely are the same. Oddly I measure the galaxy as being at the location of the cluster rather than the other way around. Though my software might be fooled by the star directly to the south. I've had that type of error before. NED shows no redshift data for the galaxy.

14" LX200R @ f/10, L=5x10' RGB=2x10x3, STL-11000XM, Paramount ME

Related Designations for NGC4068

NGC4088

Arp 18/NGC 4088 is in Arp's category for detached segments. I take it to be the piece on the northeastern end. It has a redshift that's 595 km/s while the galaxy has a redshift of 757 km/s So could it be an entirely separate galaxy? Or is the difference due to that part of the galaxy rotating toward us? NED considers it part of the galaxy. A southwestern clump has a similar difference but is receding. For this reason, I am going with NED that it is a part of the galaxy. Since NGC 4088 doesn't appear to be interacting with NGC 4085 at the bottom of my image the question remains as to what caused this odd detached piece?

NED classifies NGC 4088 as SAB(rs)bc HII, the NGC Project agrees as does Seligman. A very rare agreement for all three! The galaxy was discovered by William Herschel on March 9, 1788. NGC 4085 is classified by NED as SAB(s)c:? HII as does the NGC Project. Seligman is silent as to its classification. NGC 4085 was also discovered by William Herschel but on April 12, 1789, over a year later. Both are in the original Herschel 400 list. My comments about Arp 18 (I didn't know it was an Arp galaxy at the time) from May 4, 1984 on an excellent night with my 10" f/5 at powers up to 150x reads: "Bright easy oval, somewhat brighter to the northeast (detached segment?) Nucleus ill-defined." My entry for NGC 4085 the same night with the same scope reads: "Small faint oval with bright center. Fits in the same 150x field with NGC 4088. Nice pair." The last two words were penciled in at a later date and are not part of the computer file, only the printout.

14" LX200R @ f/10, L=6x10'x2 RGB=2x10'x3, STL-11000XM, Paramount ME

Related Designations for NGC4088