NGC2985

NGC 2985 as a spectacular spiral 2.6 degrees north of M82 in Ursa Major just below its border with Draco. Redshift puts the galaxy 64 million light-years distant while a Tully Fisher measurement says 67 million light-years in very good agreement. The spiral has a rather bright flocculent inner spiral that is mostly red with some blue segments surrounded by a huge diffuse blue arm or arms. Most literature says it is a single arm but I think I can trace two that may come from the inner structure. In any case, it is quite a beautiful galaxy that for some reason is rather ignored by the amateur community. Maybe due to its proximity to the far more famous M81 and M82.

The galaxy was discovered on April 3, 1785 by William Herschel. He had an error in the position that wasn't caught until 1863 by Heinrich d'Arrest. Later in 1865 George Rumker independently found and reported the error so some sources give all three credit for its discovery. I've also seen it claimed that John Herschel found it in 1831 but didn't realize it was the same one his dad had seen earlier. It is in the original Herschel 400 list. My notes from April 15, 1985 reads; "Interesting nearly round galaxy with a bright center and mottled outer halo. Several star clouds sen with averted vision. Bright center seems elongated with averted vision but round with direct vision. I must look at this one again on a better night." I noted the night to have poor transparency due to humidity. I was using my trusty Cave 10" f/5 that sits in my present observatory. I apparently never went back for a second look. At least none is recorded.

Galaxy surveys don't cover this region either so the annotated image has only one other galaxy noted with redshift data and it's on the very western (right) edge of the frame. I have annotated all galaxies NED knows about which isn't very many. Even some rather large ones with detail aren't in NED even as something other than a galaxy. I've marked the brighter of these with a question mark to indicate how poorly this area has been covered even by the pros. But NGC 2985 itself has been studied a lot for many things including heating of its disk and how that modifies the thickness of the disk. Though I found very little on its duel structure with the bright inner region of arm segments and faint outer ringlike but knotted area. I wonder if the outer structure will evolve into a ring as is seen around M94 and similar galaxies.

An amateur processed image of the core of this galaxy using only IR and red filters, so the colors are false, is at: http://commons.wikimedia.org/wiki/File:NGC2985.jpg The processing only picked up the very core region. It is rotated about 30 degrees counterclockwise from my north up image. The bright star at the lower left is directly left on the edge of the bright core in my shot. The two orange stars on the other side of the brighter region in my shot are to the upper right and well beyond what appears to be the edge of the galaxy. I suspect the processor did this to simplify noise reduction issues from cosmic rays and other issues. Correctly processed it likely would show detail where this image is black.

This was taken on what I'd have called an average night but considering what I've been imaging through for the last couple years and especially the summer, fall and winter it was a surprisingly good night, one neither the Clear Sky Chart nor any weather bureau predicted would even be clear. Sometimes you get lucky.

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

Related Designations for NGC2985

NGC2998

NGC 2998 is the major galaxy in a group of 6 to 8 galaxies about 220 to 230 million light-years distant that sits between the paws of Ursa Major. It is a huge spiral. Assuming 230 million light-years it is some 230,000 light-years across. It is classed as SAB(rs)c by NED and simply as Sc by the NGC project. Its huge size dwarfs the other galaxies in the group. NGC 3005, a warped Sb spiral is small by comparison yet 110,000 light-years across. This would be considered a large spiral but for the presence of NGC 2998 looming over it.

The warped disk of NGC 3005 would seem to indicate it has had some sort of run-in with another galaxy in the group. But its distortion is minor compared to that of MCG +07-20-052 which is listed at NED as being a double galaxy though looks like 3 to me. MCG +07-20-052 NED01 is the only one with redshift data. NED makes no attempt to classify it or MCG +07-20-052 NED02. 01 looks a bit like an edge on but is blue so more likely an irregular of some sort. NED02 seems to be round, again blue so likely an irregular. But what about the streak above NED01. Is it considered part of one of the other two? Nothing at its position is listed in NED, not even as part of a galaxy. I've marked it with a question mark in the annotated image. So is this two or maybe three interacting galaxies or the one galaxy torn apart by a run-in with some other galaxy in the group? I find nothing on it. I'll assume it is a two or three dwarfs that may or may not be interacting. Since the entire complex is some 75,000 light-years across I'm stretching to call these dwarfs. Large low surface brightness irregular galaxies maybe but its large for that as well. I sure wish someone would study this mess and figure out what is going on here. In the meantime how the heck did Arp decide not to include such a mash-up in his Atlas of Peculiar Galaxies?

NGC 3002 is just a star. However, some catalogs list it as being the mash-up MCG +07-20-052. It was "discovered" by Lord Rosse or more likely an assistant Bindon Stoney. The same night they found the double star NGC 3000 and another single star NGC 3004. January 25, 1851 must have been a hazy night Birr Castle. Though to their credit, they did discover the real galaxies NGC 3004, NGC 3006 and NGC 3008 that night as well. In their defense, the stars were likely right at their magnitude limit. That can cause a star to sometimes appear fuzzy, especially if seeing wasn't all that great. George and Bindon Stoney were brothers working for Lord Rosse who often took credit for their discoveries. Bindon's middle name is Blood which I've always found interesting wondering its source.

NGC 2998 was discovered by John Herschel on March 23, 1835.

There is one asteroid that photobombed the image. Details are in the annotated image. At an estimated magnitude of 17.8, it is much brighter than those I normally pick up.

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

Related Designations for NGC2998

NGC3020

NGC 3016, 3019, 3020, 3024 is a 4 galaxy group according to many catalogs. Really it is a pair of two galaxy groups as the first two have a redshift putting them 420 million light-years from us while the last two are much closer at about 80 million light-years. I see no sign of interaction between the latter pair but the more distant pair may have had a minor interaction in the past. NGC 3019 has a plume on the northeast end while NGC 3016 has a rather unsymmetrical arm structure. This may be a coincidence.

NGC 3016 and NGC 3019 were discovered by R. J. Mitchell on March 21, 1854.
NGC 3020 and NGC 2324 were discovered on March 19, 1784 by William Herschel but neither is in either H400 program.

These galaxies are located in Leo. NGC 3016 is classed as Sb by both NED and the NGC project. NGC 3019 is an obvious spiral but not classed by NED. However, the NGC project says Sbc. NGC 3020 is classed as SB(r)cd by NED and SBc by the NGC Project. It is very splotchy with ill-defined form. NGC 3024 is listed as Sc by NED and simply S by the NGC project. Being so close to edge on judging the arm structure is difficult.

As mentioned, NGC 3020 is full of knots. There's an orange star at the western end that could pass for a separate galaxy. One blue spot in the galaxy is listed by the SDSS as a separate galaxy, SDSS J095004.52+124826.6. Its redshift is virtually the same as that of NGC 3020. Another knot is listed as part of the galaxy. I really see no difference between this one classed as a galaxy and others that are considered knots in the galaxy. I've marked it on the annotated image, whatever it is.

There appears to be a third member of the NGC 3020-24 group. It is a dwarf northeast of NGC 3024. It is apparently a radio galaxy as it is AGC 192239. AGC is the Arecibo General Catalog. Is it strong in the radio frequencies because it interacted with one of the other two or is this just natural to the galaxy? I don't know.

The image contains 7 asteroids down to 21st magnitude. Several others are seen in the raw FIT image stack but are very faint unless stretched further than the rest of the field needs. The seven are identified in the annotated image. I've listed them below along with their estimated magnitude from the Minor Planet Center.

(96521) 1998 RF9 20.0
(155748) 2000 SV95 19.6
(67184) 2000 CS4 19.7
(27287) Garbarino 18.5
(2435) Horemheb 19.1
(6986) Asamayama 18.0
2011 CL5 21.0

The name citations for the three named asteroids read:

(27287) Garbarino = 2000 AC112
Guido Garbarino mentored a finalist in the 2011 Intel Science Talent Search, a science competition for high-school seniors. He teaches at the Mamaroneck High School, Mamaroneck, New York, U.S.A.

(2435) Horemheb = 4578 P-L
Named for the last pharaoh of the eighteenth dynasty in ancient Egypt. His tomb was recently excavated by a joint British-Dutch expedition.

(6986) Asamayama = 1994 WE
Mt. Asamayama is a triplex stratovolcano at the border of Gunma and Nagano prefectures, with an altitude of 2565 m above sea level. It has a 350-m-diameter crater called "Okama", where smoke still rises. It is known as one of the most active volcanoes in Japan.

The galaxy cluster in the southwest (lower right) corner of the image is GMBCG J147.27767+12.57316 at 3.6 billion light-years. Again no size is given. It contains 10 members according to NED. Only the BCG seems visible in the image though there's a hint of something right beside it to the east so I drew the line a bit further from the galaxy than normal so as not to hide this faint whatever. Doesn't look like noise. The cluster may run off the edge of the image.

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

Related Designations for NGC3020

NGC3044

FGC 965 also known as NGC 3044 is a neat flat galaxy in Sextans some 75 million light-years distant by redshift. NED has 4 other estimates ranging from 65 to 71 million light-years, a rather good agreement for a change. NED classes it as SB(s)c? while the NGC project is more certain saying SBc. It made my list for two reasons. One is the odd plumes that it has. The one north of the western arm is the stronger but there's a similar but much fainter one north of the eastern arm. Both are tilted about the same amount with respect to the galaxy's disk. The other reason is that I'm imaging the "better" entries in the Flat Galaxy Catalog. It certainly met that requirement even without the plumes.

Oddly none of the papers I read mention the plumes. They are all tied up with H alpha emission bubbles and HI regions none of which seem to correspond to the plumes. I was unable to learn a thing about them. The galaxy is rather isolated with nothing in the area that could have interacted with it other than some very small dwarf galaxies like the one off its southeast end with a similar distance. They may be due to it having digested one of these small galaxies in the recent past. Even papers giving physical descriptions of the galaxy fail to mention these odd features. They mention its lack of a core and central bulge, its HII regions (too small for my resolution) and its dust lane as well as its knotty appearance but none mention these tilted regions apparently "above" the plane of the disk. The galaxy was discovered by William Herschel on December 14, 1784. It isn't in either of the first two H400 projects.

There is a lot of quasars and quasar candidates (UvES) in the image. Usually, these are all more distant than the galaxies in the image. But in this image, there is one galaxy listed at over 7 billion light-years (has to be a monster of a galaxy) and quasars at one third that distance. Adding to the confusion is one object, SDSS J095350.35+012408.1, near the bottom center of the image. While some sources list it as a quasar others, including NED list it as a Seyfert 1 galaxy. At a distance of 5.39 billion light-years, it is in a range of many galaxies in my image as well as quasars so that is of little help. I've just listed it as Q/G rather than take sides. The most distant galaxies are very faint, you likely will need to enlarge the annotated image to see them. As usual, all labels are to the right of the object and list distance in billions of light-years using NED's 5 year WMAP calculation.

There are quite a few galaxies in the 1.25-1.29 billion light-year distance range. They are likely related. NED lists several galaxy clusters at this distance in the image but none give a size and most show no galaxy at their location making it hard to tell just what is in the group. I didn't annotate them for this reason. One group near the top of the image has a huge Big Cluster Galaxy at its center and is listed with 16 members. Having an obvious core I did list it and another entry that may be for the same cluster that has the same redshift and nearly the same location. This latter cluster has no galaxy count. Neither have a size. The latter is RXC J0953.6+0142 while the major one is SDSS-C4-DR3 1212/MaxBCG J148.42240+01.70065.

There are three rather faint asteroids in the image with short trails. Short trails indicate they are nearing the end of their retrograde motion and are about to reverse to their "normal" eastward motion in the sky. They are identified in the annotated image.

Again, I found a galaxy on the western edge of the image not listed in NED at all. Usually, they are blue when this happens but not in this case. I still don't understand why some are missed by NED when it picks up many way too faint for my system.

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

Related Designations for NGC3044

NGC3077

NGC 3077 was taken under moonlight but have managed, after several attempts, to get rid of most of the gradients. Most know M82 tangled with M81 in the recent past and that turned M82 into a starburst galaxy. NGC 3077 also tangled with M81, probably before M82. While it isn't a starburst galaxy it certainly doesn't look anything like it probably did before the encounter. The scattered and random looking dust lanes throughout the galaxy seem to indicate this was a spiral galaxy before the encounter. Now it is just a mess. NED classifies it as I0 pec while the NGC Project says Sd and Seligman comes up with Sd??. I vote for a mess.

I had wanted to show the distant star-forming regions but the moonlight pretty much made that impossible. The regions still show but not their connection to the main galaxy. Look down and to the left of the galaxy. I've attached a blow-up of the region with 6 outer star clusters marked as well as a large star cloud much closer to the galaxy. These contain stars only a few tens of millions of years old indicating this encounter wasn't all that long in the past. Similar star clouds were imaged between M82 and M81. These, however, seem gravitationally bound to NGC 3077.

You can read more about the galaxy and see a film photo of it taken in 1974 at: http://www.messier.seds.org/Pics/Jpg/n3077.jpg Notice how much more a small scope with a CCD can image today than could the 150" scope on Kitt Peak using film could back in 1974.

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

Related Designations for NGC3077

NGC3079

NGC 3079 and NGC 3073 are a pair of galaxies that have interacted in passing. NGC 3079 is the big one in the center. To the right of it and down a bit is NGC 3073. The small blue spiral is CGCG 265-055. The two NGC galaxies are at a distance of 59 and 57 million light years (7073 and 7079 respectively. CGCG 265-055 is 64 million light years and while apparently related isn't considered to be interacting from the notes I can find. Odd as its very blue color would indicate massive star formation which can be a sign of interaction. Yet 7073 shows little star formation going on. NGC 7079, however, shows major signs of interaction. Its disk is severely warped. It appears like the core is bouncing up and down (or right to left at my view angle) and has been caught far to the left. I find papers citing NGC 3073 having a young stellar population indicating rapid star formation is going on. Yet I see no sign of it in the photo while CGCG 265-055 shows the obvious signs of such star birth. Yet that isn't mentioned in the papers I saw. I'm confused.

Adding to the confusion most papers call 3079 a LINER galaxy meaning it has an active galactic nucleus (Edit: Now that's not considered necessarily true). One paper though says it is so active it should be classed as a type 2 Seyfert yet another says they find too little evidence to even say it has an AGN (Active Galactic Nucleus). Sure would be nice if they agreed better than this.

We'll settle for it being a rather pretty edge-on disturbed galaxy and leave it at that. Both were discovered by William Herschel on April 1, 1790. NGC 3079 is in the original H400 program. My entry with my 10" f/5 on April 15, 1985 with my 10" f/5 on a very humid night at up to 150x reads; "Large, long streak of a galaxy. Seems to break into two parts toward the northwest end or is this yet another galaxy? I'll have to return to this again on a better night!" I didn't do that. I suppose the dust lane near the top of the galaxy plus the field star likely at the limit of my naked eye visibility on this poor night might have combined to give this effect.

There is a QSO above this galaxy just out of my frame. Arp and others at one time argued this couldn't be a coincidence. Even though red shift showed the galaxies to be nearby and the QSOs to be distant this had to be an illusion as there were just too many quasars beside galaxies for there not to be a connection. It's now known this is wrong. Seems in studying galaxies astronomers would notice quasars in the same field. But since they weren't studying empty space without galaxies it wasn't realized how common they really are and nearly any field you pick will have one or two in it. Thus it is to be expected that some will be found near studied galaxies. The number found now near galaxies fits well with the average density of quasars in the sky so this idea of a connection between them has faded away though some still cling to his idea.

This quasar is so interesting it has its own post. See my entry for Twin_Quasar

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

Related Designations for NGC3079

NGC3090

NGC 3090 appears to be the anchoring galaxy for a loose group of galaxies about 300 million light-years from us. I find two groups listed at NED, WBL 248 consists of the 7 major galaxies in the group while MZ 03587 more than doubles that number considering the many small dwarf galaxies in the group that are almost starlike in my image. NGC 3090 is a huge elliptical galaxy. Assuming its redshift look back time is right at 290 million years then the galaxy is 200,000 light-years across. Its outer regions sort of fade away making it hard to pin down a size though the eastern edge seems rather sharp as if it is an arc of a shell left over from one of the many mergers that likely created this large galaxy. I find very little on this group in the literature, however. It seems to have only one galaxy still giving birth to stars at a decent rate, that is LEDA 1080545, a very blue spiral that really stands out among the field of rather red and dead galaxies that make up this group. FGC 114A in the lower left corner appears rather warped to my eye. A surprising number of them in my images seem curved like this one. Rarely is a disturbing galaxy in the area. This time there are several small galaxies at about its distance nearby though none look disturbed. A few are rather dense so might be able to warp a low mass flat galaxy without being noticeably distorted in the process. All of the NGC galaxies were discovered by Albert Marth on January 22, 1865.

The annotated image notes all galaxies for which NED had redshift data. Those over a billion light-years distant were usually identified only by their coordinates so are shown only as G in the annotated image. The few quasars are noted by Q. NED is now including quasar candidates with photographic distance estimates. These are quite iffy so I'm not including them unless they are also strong in UV light, a good indicator of a quasar. I did include one however that is quite blue in my image even though it wasn't listed as a UV source. I can't say it is any more likely to be correctly categorized as a quasar but the blue color can be an indicator.

There's one asteroid identified in the image. I found a second in the raw FITS but it was too faint to make it into a color composite image. Conditions went downhill as I took this data as shown by the asteroid trail getting fainter as it moved northwest during the 40 minutes of the exposure. Color data, mainly green and red, taken after the luminance were hit even worse, with the great very weak. I had to include some pseudo green created from the red and blue data much as is done when making a color image from red and blue POSS plates though with some green data to help guide the process. Also seeing was off and on lousy during the color data phase bothering some stars more than others and creating color arcs on some stars and not others. I tried deconvolving the red and green to match the blue but was not totally successful. Due to the increasing clouds, this image doesn't go as deep as usual.

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

Related Designations for NGC3090

NGC3115

NGC 3115 is one of two galaxies known as the Spindle Galaxy. It is located in Sextans about 10 megaparsecs distant (about 31.6 million light years. Though redshift puts it more distant than that redshift can be rather unreliable this close as random velocities can cause errors of over 10 megaparsecs and much more for galaxy cluster members. The galaxy used to be classed as E7 before the inner disk was discovered. Then it was reclassified as S0-. Some see a slight hook to the disk and say it is S0-/a. This galaxy is low in my skies and was deep in fog rising from the lake which cut both my resolution and limiting magnitude by quite a bit. I was unable to show any hint of the hook structure to the disk nor do I see it on any web images including some by space telescopes.

The galaxy is considered to have a super-supermassive black hole at its core that is about 2 billion solar mass in size. This makes it the closest known galaxy to beat the billion solar mass size for its core. I'd expect such a super-supermassive black hole (our galaxy's black hole is only about 0.2% as big) to be very active but NED's classification includes the PAS label which stands for a passive core galaxy. Though lots of X-ray emitting double stars are seen near its core by Chandra. See http://www.nasa.gov/mission_pages/chandra/multimedia/photo-H-11-248.html for more on this. While the X-ray image is blue in the false color composite image at this site I found the core to be slightly blue in my image while the rest of the galaxy is quite red. I don't know the source of this but it apparently has some blue stars at the core not found elsewhere. Again this goes a bit against is PAS notation at NED.

The galaxy was found by William Herschel on February 22, 1787. Being big and bright it made the original Herschel 400 list. Reading my log entry from April 15, 1985, I must have been high on something celebrating surviving another tax season and not having to work to midnight on extensions. I say this as my notes say I was seeing an obviously non-existent dust lane. It reads: "Beautiful! A small version of M-31 complete with dust lane on the western edge. Much detail seen in the spiral arms with averted vision. Oddly the Herschel program says it is round yet it is obviously highly elongated." I went on to stop the scope to 4" and it still was highly elongated rather than round and the night was listed as fair due to high humidity. I was using a 10" f/5 scope. How I saw spiral arms or a dust lane I can only imagine due to tax season fatigue. Rather than averted vision I must have been using averted imagination. Or was I on the wrong galaxy! I put it to the effects of a nasty tax season.

All sources I found consider UGCA 200 a companion of NGC 3115. They do both have similar redshift. I found only one non-redshift estimate which is less than half the redshift distance. If it is a true companion then it likely lies about the same 10 megaparsecs from us as NGC 3115. Assuming this the irregular Magellanic galaxy is about 17,000 light-years across making it a dwarf galaxy. Most sources call it unusually red for such a galaxy. Its core is slightly red though the outer region is light blue. Overall I'd call it deficient in blue rather than excessively red though I suppose this is a half full/empty glass issue.

I was surprised to find the galaxy's field was not in the Sloan survey's field so few of the hundreds of background galaxies had any redshift data. Most that did were fainter than my 20th magnitude limit due to the fog over the lake. Normally I go to about 22.5 and likely would have picked up more of them. Most of the ones lost to fog were from the MDS which stands for Medium Deep Survey which was done by the Hubble Space Telescope. Yet I found no processed images of the galaxy at any HST website.

There's one asteroid in the image. Note how its brightness varies along its track. Only one spot does it seem to show the right brightness for a 19th magnitude asteroid moving at its speed. For a bit right after that (it's moving up to the right) it almost vanishes entirely due to the fog. This gives some indication how poor conditions were. I took 5 objects this (December 18, the only December night I could open) night. All hurt severely by the fog. This fog is called "Arctic Smoke" by locals. Humidity is nearly 100% here in winter. The lake ice is warmer than the land due to the water below seeping up through cracks. This added humidity hits the colder air above the lake and turns to ice fog. As it hits shore trees they are coated with this ice with a white layer of hoar frost. I'm stuck imaging through this when shooting low in winter. This limits how low I can go in winter. At -7 degrees declination this image is about the limit unless the night is unusually dry.

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

Related Designations for NGC3115

NGC3147

NGC 3147 is a beautiful fully face on classic spiral that for some reason is overlooked by nearly all astro imagers. Why I can't imagine. As my image started to come in I saw a very faint smudge below the galaxy halfway to the bottom, several when I looked closely. I was sure it a reflection of some sort but with time short I didn't have time to move the scope and start again. I decided I'd process it out. I then went searching for deep images of this galaxy and found none. All but one went less deep than my first luminance frame. That didn't include the area of my interest. Being in an area of few surveys I couldn't find even a professional image of it that covered the right area. I then enhanced the heck out of the POSS two plates and there it was. Since the declination is 73.4 degrees it is in an area of known IFN. It's just very faint in my field. Someone who likes going for IFN should investigate this area.

NGC 3147 is a classic Seyfert 2 galaxy so very well studied, even the HST has taken it but the only amateur released images seem to exist for public display. The only one I found burned in the core region. That, of course, doesn't cover the area either.

NGC 3147 was discovered by William Herschel on April 3, 1785. While amateur imagers mostly ignore this great galaxy it is in the original Herschel 400 observing program so I assume quite a few visual amateurs in the northern hemisphere have at least seen it visually. My log entry from April 15, 1985, on a fair night due to high humidity reducing transparency at 60 to 150 power in my 10" f/5 reads: "Large, nearly circular galaxy. Seems much larger than indicated. I'd guess it is 6'x5'. Faint halo fades away so slowly it is impossible to tell where the galaxy ends. Nucleus is star-like. This is an interesting Galaxy!" Considering I measure it at about 4.5' maximum on my image that goes beyond anything I could have seen that night I have to wonder how I got the size so wrong. I had finished all tax returns or had them on extension and was taking a well-earned break that night. How that caused me to nearly double its size I don't know but I did. Oddly, I can't find where I ever went back to it until taking this image.

Being so far north and in the Zone of Avoidance, the field is poorly studied. Only it and the flat catalog galaxy in the lower left corner had redshift data. NED had only 6 other galaxies in even listed. All are from the 2MASS survey. That doesn't even list visual magnitudes. Many other galaxies with insufficient 2-micron emission to make that survey are scattered about the image. I can't find anything on them. Being so far north it isn't surprising no asteroids made an appearance either.

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

Related Designations for NGC3147

NGC3158

The NGC 3158 group is composed of 8 NGC galaxies and many others a bit over 300 million light-years distant by redshift. NGC 3158 is a huge Elliptical galaxy whose gravity anchors the group. I get a size of 275,000 light-years for its outer reaches. It was discovered by William Herschel on March 17, 1787 and is in the second Herschel 400 object list.

Half the NGC members were found by Guillaume Bigourdan on February 1, 1886. He found NGC 3150, 52, 59 and 61, all in the southern part of the group. R.J. Mitchel working for the Earl of Rosse found two, NGC 3152 and 3160 with the last, NGC 3163 also found by William Herschel the same night as 3158. It, however, isn't in either Herschel 400 listing.

NGC 3159 is listed as an E2 spiral and as peculiar. That may be due to the very faint plume to the south. Ignoring the plume it is 67,000 light years across. The plume fades away so I'm hard-pressed to determine an edge but my best guesstimate puts it at least 200 arc seconds long making it over 300,000 light-years in size though of much lower mass than NGC 3158.

NGC 3160 is a strange spiral likely involved in a collision to create its odd structure. It is about 83,000 light-years across. NGC 3151 at 60,000 light-years is an SA0 Galaxy/ NGC 3152 is also rather odd being a ringed barred spiral with no arms, just the ring. NGC 3160 is a warped spiral seen edge on and is about 125,000 light-years wide. It appears, at least when seen edge-on, as a red spiral. Even the warped plumes off its ends are mostly red indicating no new star formation of any significance for millions of years. In fact, almost all members of the group appear to fall in the red and dead category.

NGC 3161, an E2 galaxy, is the smallest of the NGC galaxies in the group at only 57,000 light-years but does have an AGN core indicating it is still reacting to a likely interaction with another galaxy not too long in the past.

NGC 3163, Herschel's other discovery is quite large at a bit over 140,000 light-years and listed as an SA0-: galaxy rather than an elliptical.

NGC 3159, 3161 and 3163 appear to share a common halo indicating they may have had a close encounter with each other in the recent past. This may explain the large southern going plume coming from NGC 3159.

There are many other galaxies also likely members of the group. One without redshift data is east-southeast of NGC 3158, MCG +07-21-025. It isn't classified that I found and hard to observe as it is hiding behind a rather bright blue star. It makes it look like it is a red galaxy with a blue core.

The annotated image identifies all I found redshifts for. Only a few not members of the group. One star-like object is labeled RQ/G east-northeast of NGC 3158. RQ stands for Rejected Quasar. It apparently is just a very bright compact blue galaxy about 3.1 billion light-years distant. The Sloan image shows a slight blue disk around a bright nearly white core that is larger than a star of similar brightness. Likely it is some type of AGN, just not sufficient to be a quasar.

The minor planet center shows a periodic comet moving quite rapidly in the image but I see nothing at the position. It is 3.56 AU distant from us and 3.12 AU from the sun. One estimate puts it at 22.7 magnitude which would certainly be too faint at its speed and my lousy skies to have picked up.

Again this was a night of poor transparency though seeing was not good it was better than the previous night. Still, this image doesn't go as faint as it would under what used to be normal conditions here. The faint outer reaches of these galaxies is likely greater than I could see thanks to these less than optimum conditions.

I got one more blue image than normal because I thought one blue had been hurt beyond repair and so retook a blue image another night. Turned out I meant that comment for a different image so retook the wrong one. I used all three anyway.

14" LX200R @ f/10, L=5x10' RG=2x10' B=3x10', STL-11000XM, Paramount ME

Related Designations for NGC3158