NGC4939

NGC 4939 is another rarely seen face on spiral galaxy, about 160,000 light-years distant by redshift, located in southern Virgo about 5 degrees west of Spica and 6 degrees east of the far more well known Sombrero Galaxy, M104. It was discovered by William Herschel on March 25, 1786 and is in the second Herschel 400 Observing Program. It made my to-do list for both being a very lonely but disturbed looking face on spiral and for being on the that Herschel 400 list. At -10 degrees I need a very good night for it and this year those just didn't happen. Seeing turned awful right after I started the run but since I was sleeping I didn't know that until I went to process it.

I say it looks disturbed because in higher resolution images than I could achieve this night it is crossed by several very straight dark dust lanes. I'd hoped to pick up the stronger ones. Instead, two of the strongest blended together to make the vertical dark line just to the right of the core region. Problem is I also see hints of one to the left of the core that doesn't show on high-resolution images so has to be just noise. It could be the other one is also just noise in my image that happens to coincide with the location of the lane that really does exist there. I need a much better night though with so many good objects in this area still on my to-do list I can't see that happening any time soon.

While NED classifies NGC 4939 as SA(s)bc with a Seyfert 2 active core the de Vaucouleurs Atlas of Galaxy Types uses it as an example for a SAB(r)bc galaxy. That is having characteristics of both a spiral and barred spiral. Notes at NED also see a bar hidden in the bright reddish oval core region. The NGC Project, like NED, doesn't see a bar structure. At first glance the spiral arm structure looks rather normal for a wide open two arm spiral but on closer inspection it appears far more disorganized with the southernmost wide arm and the one inside it both coming off the same inner arm structure while the tighter arm fades away then reappears as the northern arm that doesn't begin to match the far southern going arm in structure nor match the angle of the arm it appears to be related to. The fade then reappearance of the arm at this odd angle gives the galaxy the appearance of being a three-armed spiral. Yet it is so lonely with nothing seen at its distance in the frame or for a wide area around it, it seems an unlikely candidate for having had an encounter that could account for this. Apparently, it is just natural for this somewhat peculiar galaxy.

NED lists only extremely distant galaxies so faint they barely show in my very poor data. For that reason, I didn't prepare an annotated image. Not only did the seeing go to bad a fog developed over my lake that raised my background level by a factor of 5 to 10 which would have required a lot more and shorter subs to have cut through. Since I was unaware of this that didn't happen. While the blue frames were taken before the fog but at the time of the worst seeing, I had a large discrepancy in star sizes for the color data. Green was so hit by fog only one frame was sort of usable. The other useless. Most of the green data for this one is pseudo green I created with my own technique leaving the color a bit suspect. That's the best I could do finding the problem now that the sun is in Virgo when I went to process the image. That made it impossible to get more data.

14" LX200R @ f/10, L=4x10' RB=2x10' G=1x10'+pseudo green to compensate, STL-11000XM, Paramount ME

Related Designations for NGC4939

NGC4958

The NGC 4958 galaxy group is a small group of galaxies in Virgo, 4 of which are in my image. All share a somewhat similar range of distances in mostly the 60 to 80 million light-year range. Though if you stick with just redshift or just non-redshift distance measurements they are somewhat scattered values with some having higher non-redshift distance and others higher redshift values. They may be outlying Virgo cluster members. I'm going to arbitrarily pick 70 million light-years as an approximate distance to all 4.

NGC 4958 is a rather red SB0 galaxy indicating little recent star formation. It was discovered by William Herschel on March 3, 1786 and is in the original Herschel 400 Observing Program. My entry for it from April 23, 1985 with my 10" f/5 scope reads: "Conditions poor with fog. Round nucleus with an oval halo. Center seems complex but seeing too poor to see much." I was going to revisit it but like my reimaging of objects I could have done better, that didn't happen either. Assuming the 70 million light-year distance it is about 115,000 light-years across.

The only other NGC galaxy in the frame is NGC 4948 which may or may not be IC 4156. It was discovered by Lewis Swift on May 25, 1897. Later DeLisle Stewart using an early Harvard image plate recorded 4 objects. There's nothing at the positions of any of them. These 4 were included in the IC catalog. With some assumptions about his error for objects he noted as extremely faint on this early plate the one for IC 4156 may be NGC 4948. The plate still exists but apparently, no one has gone back to examine it and determine what it shows. NGC 4948 is a rather red barred spiral classed as SBdm. There are some blue regions but mostly it is a rather dead galaxy like NGC 4958. It is about 43,000 light-years across.

The other two galaxies are listed as low surface brightness galaxies from the DDO catalog of low surface brightness galaxies. At the top of my image is DDO 163. It has bluer stars than the first two galaxies. It too is about 43,000 light-years across but its a much fainter galaxy.

At the bottom of the image is DDO 162. It is somewhat brighter than DDO 163 but smaller being only 26,000 light-years across. It is often listed as NGC 4958A though not in the NGC. It's the bluest of the bunch and appears to be a rather active galaxy.

Only one other galaxy in the image had redshift data at NED but it lies some 1.19 billion light-years away so is unrelated to the other 4. While there are a lot of other galaxies in the image I couldn't find much on them. I'd not have prepared an annotated image but there were some very faintly seen asteroids in the frame so I did prepare one to help you find them. Since I did I included a few brighter galaxies without redshift data as well as one very low surface brightness galaxy listed in NED as simply a Uv Source with its GALEX coordinates for an ID. NED doesn't even list it as being a galaxy though it obviously is one. NED lists several dozen more as IR sources from the 2-micron survey that I didn't bother to annotate. A handful carry extended PGC designations NED doesn't carry. When I asked several years ago why they said it was too unreliable and all are covered by other catalogs they do carry. Since many catalogs they carry duplicate others I'm not sure I understand that explanation. This was many years ago, maybe I should try again and see if that opinion has changed.

The night I took this image was very poor. Clouds were constantly blocking the view. Notice the asteroid trails are much fainter than normal for their magnitude and fade in and out, vanishing totally at times. Things got so bad one green frame was virtually lost to clouds. Only about 6 stars can be seen plus the core of NGC 4958. I had to throw that frame out. My color balance is a bit suspect thanks to these clouds but appears about right. There were several other asteroids in the frame that would normally have been seen but due to conditions were not visible even in the FITS files no matter how hard I stretched them. If I relied on guiding I'd have lost the guide star many times resulting in not one usable frame. Another reason why, if the mount can do it taking the time to set it up for unguided imaging can pay big dividends, especially when running under automation.

14" LX200R @ f/10, L=4x10' RB=2x10' G=1x10', STL-11000XM, Paramount ME

Related Designations for NGC4958

NGC5002

NGC 5002 is a barred Magellanic galaxy usually considered a member of the NGC 5033 group in Canes Venatici. NED's 5 year WMAP data shows it to be about 61 million light-years distant though a single Tully-Fisher measurement puts it about 40 million light-years distant. That's the distance APOD puts on NGC 5033 so I'll use it rather than the redshift-distance which is likely distorted by its motions in the group. That makes it about 20,000 light-years in diameter, rather typical for a galaxy of its type. I assume the bar is the linear structure. Odd in that it runs from the core to the edge on one side but not the other so is it a half barred galaxy? A loop of star knots runs through the galaxy. In lower resolution images it looks quite different than in my image. Then there's kkh 081 a very faint irregular galaxy at about the same redshift as NGC 5002. They may be traveling together and thus it is really about 40 million light-years distant same as NGC 5002. When I first brought up the luminance stack I thought it a faint reflection and nearly processed it out. But when I checked Jim Thommes recent image of the area I saw a very faint hint of it then found it very faintly on the POSS plates and Sloan image. There it appeared very "grainy" as it does in my image. Comparing the two the grain pretty much matches indicating the galaxy really is grainy, that is composed of faint star clouds. This is one that deserves a lot more time to see if this goes away or gets stronger. NGC 5002 was discovered by Heinrich d'Arrest on April 27, 1865.

In preparing the annotated image I came across two galaxies from the TONS12 catalog. I'd never heard of it. That stands for the Texas-Oxford NVSS Structure 12 hour region catalog. NVSS is a radio catalog by the National Very Large Array. That's the NV part, SS stands simply for Sky Survey. How Texas-Oxford fits in I don't know. Anyway, those two are radio galaxies, one, a lone distant but very bright and compact galaxy the other the bright cluster galaxy anchoring a 12 galaxy cluster in the upper right corner of my image. The distance to the cluster has been calculated photographically not spectroscopically, hence the "p" designation. The "est" for the galaxy means it is an estimate. Now how this is done I have no idea. In any case, it means both are likely less accurate than a spectroscopically determined distance.

One faint asteroid is listed in the annotated image. Details are in that image. You may need to enlarge the image to see it as it barely registered. The lack of a number indicates it has yet to complete one orbit since its discovery.

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

Related Designations for NGC5002

NGC5005

NGC 5005 is a bright spiral galaxy in Canes Venatici that's about 54 million light-years distant by redshift and 55 million by Tully Fisher measurements. A surprisingly close agreement. It is considered by some to be a companion to the much more famous, highly warped galaxy, NGC 5033 about 41 minutes to the southeast and thus out of my frame. NED classes NGC 5005 as SAB(rs)bc;Sy2 LINER while the NGC Project says, Sb (no bar). Most notes at NED refer to the bar saying it is offset from the major axis by 30 degrees. I see no hint of it visually. This is likely why the NGC Project doesn't recognize it. It seems rather dust red reddened. Is it the cause of NGC 5033's warp? It seems too normal for that. NGC 5033 has two satellite galaxies that might be a more likely candidate though it could be due to a galaxy it ate and no longer exists.

It was discovered by William Herschel on May 1, 1785. It is in the original H400 program. My entry dated April 28, 1984 with a 12.5" f/5 using up to 150x on a great desert night reads: "Stellar nucleus. Easy dust lane with faint outlying arms. Fairly bright. Good object but the arms weren't seen in my 10" scope."

Above NGC 5005 is the dwarf irregular galaxy LEDA 166157. I couldn't find much more than this about this obviously very blue, low surface brightness galaxy. It did make the Karachentseva and Karachenstev list of new nearby dwarf galaxy candidates. http://aas.aanda.org/articles/aas/pdf/1998/03/ds6146.pdf The distances to some entries were later estimated but not for entry 188 which is LEDA 166157 unfortunately. There is a newer paper on these by the same authors but it is behind a paywall so I didn't investigate further. http://cdsbib.u-strasbg.fr/cgi-bin/cdsbib?2007AstL...33..512K

As with much of the year, the weather took its toll on the image. The blue frames were very bright with a background twice that of red and green. That is very unusual. Again, I was sleeping while this data was taken so I don't know what caused the problem. Even after all my color balance tricks, the galaxy doesn't quite look right to me as to color. Might just be due to below average seeing. Certainly, the luminance frames didn't go nearly as deep as usual coming up a good magnitude short of normal skies.

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

Related Designations for NGC5005

NGC5012A

Usually, it is the major NGC galaxy I'm featuring not its sidekick. In this case, the sidekick is NGC 5012A. Probably a better name would be UGC 08290 or PGC 45884. It is what I call a "sloshed" galaxy. This is in the sense of how the yoke of a fried egg can be moved off center by moving the frypan before it sets. The galaxy's core is far off-center. That's certainly the case with this galaxy. Sometimes you can see the other half of the galaxy is there, just very faint due to a lack of bright stars. NGC 5474 near M101 is an example. In its case, it is thought its interaction with M101 caused the "sloshed" effect. You can see the rest of it faintly in my image of it. But with NGC 5012A I see no hint of the "other side". Also, NGC 5012 doesn't appear distorted enough to have had a serious gravitational interaction with it. They are at about the same distance by redshift, 130 million light-years away.

I found little on this pair. Certainly, nothing indicating any interaction. One old (1970's paper) denied interaction. Something sloshed NGC 5012A, but what? It is classified as Sm: by NED and pec? by Seligman. I couldn't find who discovered it or when. NGC 5012 is classified as SAB(rs)c LINER by NED and SBc? by Seligman. It was discovered by William Herschel on April 10, 1785. It is in the second H400 program. My log from that was lost in the move to Minnesota so I don't know if I also saw NGC 5012A. Considering that was over 30 years ago my memory is of no help.

This is one of my very early images from 2007. Even the FITS were so poor I gave up trying to rework it. I need to go back to the original FITS files to do it justice. My processing abilities were nill back then and my software limited. For instance, there's a hint of a pair of interacting galaxies just above NGC 5012A (NGP9 F379-0539970 at about 870 million light-years) but my ham-handed processing has destroyed much of the detail. I think there's a plume from the larger eastern one. But I have to either retake this or reprocess the data to know for sure. I couldn't find any deep images of this field on the net. Until I can research this one better this will have to do.

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

Related Designations for NGC5012A

NGC5014

NGC 5014 caught my eye due to its odd dust lane. Near edge-on spiral galaxies have dust lanes that go down their length bisecting the galaxy. Though those lacking dust may not show a dust lane at all. But this one has a dust lane that goes vertically through the galaxy west of the core. By some fantastic coincidence, two field stars from our galaxy mark the endpoints of this dust lane. Both the stars and the dust lane are rather a rather similar shade of red as well. I did tone them down quite a bit as otherwise, they overpowered the dust lane. I did this equally so their relative brightness difference is maintained. There is a short dust lane below the core more where one should be. Seeing wasn't up to snuff, nor was transparency. The core has a blue blob on its east side according to the SLOAN image but it was below my resolution level.

There is a small plume above and a bit left of the core that is rather blue compared to the rest of the galaxy. Could this plume be due to something it digested recently? If so that may also explain the odd dust lane as due to the interaction or merger.

Redshift puts the galaxy some 63 million light-years distant while non-redshift measurements put it a bit closer, say 56 million light-years. Using the latter distance I measure its size at 32,000 light-years. Not a large galaxy. NED classifies it as Sa? as does Seligman. It was discovered by William Herschel on May 1, 1785, though he got its position a bit wrong as did his son years later. Still, with nothing similar in the area, its identity is quite certain. As it is rather faint it isn't in either of the Herschel 400 observing programs even though it is well positioned for northern observers in Canes Venatici.

The field contains the usual assortment of distant galaxies and quasars as well as a small galaxy group known as SHK 248. As I'm starting to go through this catalog by Romelia Shakbazian for interesting groups such as this one I was pleasantly surprised to find one of her groups in the image. So I went to Google to find out more. That gave me an all too often result. The only citations it came up with of other than papers discussing the entire catalog were mine from two years ago. https://www.cloudynights.com/topic/405703-back-to-obscure-satellite-galaxies-holmberg-viii/

I won't repeat what I said there but can add a bit. The count is 9 galaxies according to NED. One has an identity problem discussed in the above link. Another SHK 248:[STC97b] 04 in my annotated image is actually two very close galaxies. Neither time was seeing sufficient to split them, unfortunately. But I can't get 9 galaxies. By definition of SHK groups, all should be easily within my grasp but I only get 6 or possibly 7 if ASK 519408 is included (see the link for more on this. There are three objects in a line at the top of the group but only the middle, slightly blue one, is a galaxy, the other two are stars. Also, the bright orange object at the end of a curving chain starting from the double galaxy is just a star. So where are the other two or three members? All I can come up with is that she mistook the aforementioned stars as galaxies. Easy to do working from the POSS plates rather low resolution.

In case you are wondering here are the requirements for inclusion in her galaxy group catalog:

*They must contain 5–15 member galaxies.

*Each galaxy's apparent magnitude in the POSS red band must be comprised between 14m/19m.

*They are compact, id est the relative distances of the member galaxies are typically only 3/5 times the characteristic diameter of a member galaxy.

*Almost all galaxies must be extremely red; there must not be more than one or two blue galaxies.

*Galaxies are compact (high surface brightness and border not diffuse).

*The group must be isolated.

I'm not sure this one meets the red galaxy requirement. The northern member is blue as are the easternmost two in the bottom curve along with the one nearest the double galaxy. They too are somewhat blue or at least not all that red. That makes me think she included the three red stars as galaxies bringing the count up to 9 if the questionable one is included and the double is listed as single. The clusters were identified from the red POSS I plates which didn't have the resolution to split the double galaxy so I suspect it counts as only 1.

As an extra bonus, it turns out my 2012 image of the galaxy group could be easily combined with this image to make a much wider field. Its main target was Holmberg VIII from when I was taking the Holmberg galaxies. So I made a hasty combine of the two. This makes for a larger than normal image but is a nice one. Since conditions were quite different and my processing software has changed some I really should have processed the older image to be a better match. So don't look too hard for the seam as the change in signal to noise ratio is rather obvious thanks to the poorer transparency this spring.

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

Related Designations for NGC5014

NGC5033

NGC 5033 is a much imaged spiral galaxy in Canes Venatici. Distance estimates range from 38 to 60 million light-years. NED's redshift and non-redshift measurements put it about 55 million light-years out while APOD says 40. It is classified as SA(s)c;HII Sy1 at NED. Seligman simply says Sc?. In any case, it is a rather disturbed galaxy. That may explain its Seyfert 1 status. The arms appear pulled out and highly warped out of plane. They are rather faint making this a more difficult imaging target than many beginners realize. Virtually all my posts have north at the top. This is an exception. East is at the top with north to the right. It looked better to my eye flat than on edge. While neither NED nor Seligman see a bar one paper I saw said it may have a triple bar but most deny it has any bar at all, even those using the same images that first was said to show the triple bar.

This is another of my early images and needs a lot of work or a reshoot. I didn't do much if any research on my objects back then. For now, I'll just say it was discovered by William Herschel on May 1, 1785. It is in the original H400 program. Apparently, I wasn't much impressed as my notes from April 28, 1984 simply say, "Smaller, fainter version of NGC 5005. But still a good object. Several unplotted (on my atlas) seen in the area." It appears I wasn't seeing the arms at all, just the core region. Not surprising as they are rather faint.

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

Related Designations for NGC5033

NGC5053

NGC 5053 is a rather distant globular cluster in Coma Berenices near the much brighter and more famous M53 globular. It is probably about 53,000 light-years away. I measure it at about 160 light-years across, rather large for a globular. For being so distant it appears rather large in angular size but not at all condensed like many globulars. It is being torn apart by tidal forces and has a 6 degree long tidal tail stripped by our galaxy's gravity. It was discovered by William Herschel on March 14, 1784. It is in the second H400 program. Some say it may be a captured globular that originally belonged to the Sagittarious Dwarf Elliptical Galaxy. That galaxy wasn't found until 1994 and is now being eaten by our galaxy.

There are quite a few background galaxies in the image. This is a very old image before I did any research so I have nothing on them as yet. The most obvious to the northwest is PGC 46161. It is about 60 million light-years away. The rest will have to wait until I have time to work on this one and reprocess the very old image. There is one asteroid in the image. It is (184248) 2004 SX11 at a predicted magnitude of 19.6.

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

Related Designations for NGC5053

NGC5068

This is one of my failures. Still in keeping with posting those as well as the successes here goes anyway.

NGC 5068 is a face on, nearby spiral galaxy in southern Virgo. Redshift measurements are rather inaccurate for nearby galaxies. Using other methods NED comes up with a distance of 20 million light-years while others like Wikipedia say 22 million light-years. The galaxy has a lot of HII regions and O stars that are bright enough I should have picked them up but that didn't happen but for one HII region. The galaxy was discovered by William Herschel on March 10, 1785. It is in the second Herschel 400 Observing Program of the Astronomical League.

The galaxy is at 21 degrees south, 6 below my usual cutoff declination. On really good nights I can catch some detail this low. Unfortunately while the night started out fairly decent I started with color data when it was lowest but as it approached the meridian seeing kept getting worse so my usual tactic of capturing luminance nearest the meridian backfired with the red data taken lowest in the sky the best. Also transparency, never good this low, also went down hill so it doesn't go as deep as I normally do. This one is in dire need of a retake if seeing ever allows it. Stars are elongated due to atmospheric dispersion this low in the sky. It was made worse by the deteriorating seeing.

For a HST image of the galaxies central region see: https://en.wikipedia.org/wiki/NGC_5068#/media/File:NGC_5068_HST_Wiki.jpg

The bright asteroid is 13th magnitude (247) Eukrate. It is most likely a carbonaceous asteroid. Radar data shows it to have a diameter of 83 ± 9 miles. It was discovered by Robert Luther on March 14, 1885. It is named for a sea nymph of Greek mythology.

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

Related Designations for NGC5068

NGC5100

On January 23, 1784 William Herschel found a galaxy. He recorded the RA but not the declination except in general terms. He never went back to it. Tempel decided it didn't exist. Dreyer, after consulting Herschel's notes decided it was the same galaxy Marth had found on March 22, 1865. Still, he gave it two numbers, 5100 for Marth and 5106 for Herschel. There's some question however that 5100 really is what WH was trying to record that night. For more on this see notes for either galaxy at the NGC Project.

Today NED not only considers this galaxy NGC 5100 but also lists the interacting spiral to the northwest as part of NGC 5100 making it a double galaxy. But the entry for NGC 5106 only refers to the bright galaxy. It appears neither Marth nor either Herschel saw this companion. The companion carries its own designation on several catalogs including VII Zw 295 which is the catalog entry that attracted this pair to my attention in the first place. The pair are in north central Virgo, 450 million light-years distant. I measure the NGC galaxy at 130,000 light-years across. Likely that has been increased due to interaction with the companion. It will likely settle down to a somewhat smaller size. I measure the companion at 120,000 light-years across, nearly the same size but it appears even more drawn out by the interaction as it has one well-formed arm on the west to north while the eastern south going arm is an ill-formed squiggle, that likely was a nice arm before getting mangled in the collision. Assuming they actually are at the same distance their centers are only 90,000 light-years apart. Likely the separation is considerably greater. Still, I wish there was a way to create a time-lapse movie of what has happened to these two and what will happen in the future.

To the northeast is a ring galaxy ASK 450821.0 at 650,000 light-years. The core is off center but the gap between the ring and core is not nearly as empty as in many rings. I found nothing on it. I measure it at a bit over 60,000 light-years across at its redshift distance. This takes into account it was slightly closer when the light we see started on its way here and thus is seen slightly larger than it would if we saw it's light at its redshift distance. I usually start making this adjustment at 500,000 light-years look back time.

Three rather faint asteroids snuck into the image. See the annotated image for their details.

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

Related Designations for NGC5100