NGC5915

USGC S244 is a trio of interacting galaxies in central Libra about 110 million light-years distant by redshift measurement. The trio is composed of NGC 5915, NGC 5916 and NGC 5916A. All three appear significantly distorted by tidal interactions. I wish we could see a time lapse movie of the last few billion years to see how these three have tangled over that great time. While they all carry rather ordinary classifications, one note says of NGC 5915, it lies outside the classification system but then goes on to classify it anyway. NED's classification is SB(s)ab pec.

Of the three, NGC 5915 seems the most strange and has massive star formation occurring as shown by the mass of star knots near and around its core. Most blend, due to my poor seeing this low in the sky, into a mass that looks somewhat like a bar though those around the edges do resolve. The galaxy is listed as having a strong HII emission from all parts but is strongest from the lower arm. Unfortunately at a redshift of z=0.007 it lies outside the pass band of my H alpha filter so I can't pick it up. I think the orange object right where the southern arm meets the bar is just a field star in our galaxy though in the Sloan image it comes out green for some reason. An orange star normally wouldn't do that so it may be a real feature of the galaxy. It isn't a large galaxy with a size of only about 40,000 light-years. However if you look really close you will see a faint plume to the north that if included brings it to about 51,000 light-years.

To the south NGC 5916 is somewhat more normal looking if you ignore the large plumes. NED classifies it as SB(rs)a pec In this case the galaxy is turning quite red but for these plumes indicating star formation pretty much ceased over a billion years ago. The arm on the eastern side of the core has a field star in it that, while it looks like it is part of the galaxy is actually just a star in our galaxy. Thanks to its large plumes it is some 100,000 light-years in diameter. Though I suspect prior to the interaction it was about the same size as NGC 5915.

Both were discovered by John Herschel on the night of June 5, 1836.

NGC 5916A is a somewhat more normal looking galaxy but still classified as peculiar. It is considered an SB(s)c pec galaxy though I can't see enough of its arm structure to see how that was obtained. When I went to image this trio The Sky Pro 6's database listed both it and NGC 5916 as NGC 5916, no "A" used. So it seemed to say both were the same. Though when I told the scope to slew to 5916 it went to the right one and it also went to the right one when I entered 5916A. Just that its on screen identification of them is messed up. Internally it knows which is which. I found this very confusing when I went to add it to my to-do file.

Being low in the sky and approaching the Zone of Avoidance this field is very poorly studied as to galaxies. Only one other galaxy had redshift data. Normally I'd not have bothered with an annotated image for such a poorly studied field but it did contain three faint asteroid trails that likely couldn't be found unless I did point them out. Thus I made a very sparse annotated image. The fourth galaxy is 12 times more distant and thus not related to the three that make up USGC S244. Many others are seen faintly in the image. Only a half dozen were even listed at NED, all without even a magnitude let alone any distance data. I didn't bother noting them as they are listed only by coordinates.

Being so low in the sky this is one difficult area for me to image. The horrid conditions I've had for many months now made things even worse. While this was taken the best night I had this spring it still was a poor night. A lot of detail both faint and fine was lost to poor seeing and transparency. The poor conditions meant that out of the 10 asteroids in the field only three were bright enough for me to pick up. On a good night all should have been within range. This was a field for confusion as to asteroids as well. One I do very faintly show though it may not show in the annotated image unless you enhance the heck out of it, is (431687) 2008 DZ34. The minor planet center listed it twice, once with the 431687 number and once without. Without it had a note that reobservation of it in late May through June was desired. The entry with the number had no such note. It is lost in my neighbor's trees at that time and almost at the horizon so I won't be helping them out.

Besides lousy conditions the sky suddenly cleared with just time to grab this field before it vanished into my Meridian Tree. I had no time to properly cool the scope. It had been raining earlier so I couldn't open to cool in case it cleared. This is why the stars are particularly wonky looking. Hot air trapped along the top of the SCT tube creates flat sided stars. This low I have only a small window between trees I can't cut down due to lakeshore regulations so I put up with wonky stars from time to time when its the only chance to get the object.

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

Related Designations for NGC5915

NGC5921

NGC 5921 is a pretty face on barred spiral galaxy in Serpens Caput about 3 degrees north of M5. It is well worth visiting when viewing the far more commonly targeted M5. Its distance seems poorly understood. Redshift puts it at 70 million light-years. A 1988 Tully-Fisher determination says 82 but a 2009 T-F measurement came up with 46. An analysis of supernova 2001X says 67 which is in good agreement with the red-shift measurement. Still, based on the star clouds I see in the galaxy I would have to think the closer 46 million light-year estimate is closer to the correct distance. I doubt I'd resolved these as well at the longer distances. NED classes it SB(r)bc LINER. The NGC project says SBbc. It was discovered by William Herschel on May 1, 1786. It isn't in either of the H400 programs.

While NED shows thousands of galaxies in my image only one has a redshift. It is CGCG 049-140 at 580 million light-years. It is the round blue galaxy at the very top of the image a bit right of center. None of the other galaxies had a redshift at NED. All the other galaxies are from either the 2MASS catalog or the Sloan survey. Except for three in the extended PGC catalog, none of the rest made any secondary catalog.

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

Related Designations for NGC5921

NGC5943

This field contains 4 NGC galaxies, all either interacting or distorted by past interactions plus a 5th rather normal one. The field is located in northeastern Bootes. All are likely members of the same local group about a quarter billion light-years distant by redshift measurement. One or two "lesser" members of the group are in the field as well.

NGC 5934 and NGC 5935 are an obvious pair of interacting galaxies. Both have plumes drawn out of them by the interaction. NGC 5934 is listed as a spiral of questionable classification. NGC 5935 is listed as S? as well by the NGC Project but NED leaves off the question mark. To me, they both look odd. I wouldn't argue with NGC 5935 being S0 but 5934 looks unquestionably spiral to me. Maybe they mean they can't decide what type of spiral it is, barred or not barred. Below the pair is KISSR 1955 a starburst galaxy with a faint outer halo. Starburst activity can be triggered by interaction with another galaxy but this isn't necessary.

NGC 5945 is a nice face on barred spiral whose arms overlap making a pseudo-ring. Besides these rings, there are two outer arm segments that see to make huge "ears" on the east and west sides of the galaxy. Inside the ring on the west side is a "bright" object listed as SDSS J152943.21+425511.2, a star and [BFW2006] J232.42996+42.91977 a galaxy. So is it a star or a galaxy. Its distance measurement is about the same as NGC 5945 but it is a friend of a friend estimate rather than spectroscopically determined. So is it a star or a galaxy? Of NED's 5 entries for this object 4 call it a galaxy. While it is hard to measure the PSF of an object on top of another what I am seeing is identical to a star of similar magnitude in the image. That would indicate it is quite small in angular size, more like a star than a galaxy but if this is all that's left of the core of a cannibalized galaxy. That might explain the "ears".

The main target of my interest in taking this field, however, is NGC 5943. This galaxy is very fuzzy with large plumes. I didn't realize how large when I took this image or I'd have put a lot more time into it (weather willing which likely would not have allowed it). Faintly seen in my image are two huge plumes going to the northwest and southeast. It too has a near starlike companion, ASK 245539.0. Though its PSF is very galaxy like so easy to confirm it is a galaxy. Usually, plumes like those seen in 5943 are due to a merger. In this case, it might be that the companion is still in the process of merging. Note the brightest part of the plume leads nearly to ASK 245539.0. Unfortunately, I find no papers on either NGC 5943 or NGC 5945.

The ordinary looking NGC galaxy, NGC 5947 is a rather pretty face on barred spiral with many arm segments. I didn't think about it when picking the center coordinates for the image as I was thinking only of the other 4. This resulted in it being chopped off on the eastern side. The other nice spiral in the image is CGCG 222-012. Smaller than NGC 5947 and tilted at a rather steep angle it is difficult to see its structure. While no bar is seen nor is it classified as a barred spiral the arms I see seem to start well out from the core as if coming from the ends of an unseen bar. It too appears to be a member of the same group as the others. Several more are out of the field.

NGC 4934, NGC 4935 and NGC 4945 were discovered by Édouard Stephan on June 12, 1880. He found NGC 4943 and NGC 5947 on June 18, 1880.

Unfortunately, seeing was very poor for this image. There's a lot of fine detail in all of these galaxies I failed to pick up due to the seeing. I hope to try again for it if the weather ever permits. This isn't representative of the field I'm sorry to say.

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

Related Designations for NGC5943

NGC5949

NGC 5949 is a very flocculent galaxy in Draco just under Ursa Minor. Redshift puts it only 21 million light-years distant. However, the redshift value is rather unreliable at such close range due to the galaxies own motions likely being greater and thus swamping the cosmological measurement. Various Tully-Fisher measurements cover a rather large range from 33 million to 63 million light-years. The most modern estimates are coming in at about 45 to 50 million light-years which pretty well matches the resolution of its features in my image. I'll go with the lower end and say 45 million light-years. That makes this little feller about 30,000 light-years in diameter. NED classifies it as SA(r)bc? though how you find spiral arms in all those segments I don't know. The NGC project says more simply Sc and Seligman says Sbc. The galaxy was discovered on November 28, 1801 by, who else, William Herschel. It isn't to be found in either of the Herschel 400 lists. So why did I take it? I like flocculent galaxies and this one is so flocculent I see no hint of a spiral pattern in the so-called arm segments. Some of these are HII regions according to notes at NED but they indicate these regions are faint so I didn't try the H alpha filter on them even though this is one of the rare galaxies with a low enough redshift the emission is within my 6nm wide passband.

This galaxy has low contrast in its flocculent structure compared to most of its type such as NGC 2976 and the very high contrast NGC 4605. All have been processed to about the same contrast level.

While NED lists over 2500 galaxies in my field this is the only one with a redshift value. NED lists one QSO candidate that is seen through the galaxy but even in the Sloan image, I can't see it so it certainly isn't in my image. NED lists two other quasar candidates I can find but NED lists them first as stars which indicates it feels they likely won't hold up when the final research is in. The Minor Planet Center reports that out of the 791,260 asteroids it is tracking not one brighter than 23rd magnitude is in my frame. Thus I didn't bother to prepare an annotated image.

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

Related Designations for NGC5949

NGC5963

NGC 5963 and NGC 5965 are a nice pair of interesting, but unrelated, galaxies in Draco. NGC 5963 is a low surface brightness galaxy except for its core region which I had to greatly attenuate so it didn't overwhelm the image. It is thought to be rather close by but distance measurements vary wildly. Redshift would put it about 32 million light-years away. Tully-Fisher measurements range from 48 to 110 million light-years. All the more modern Tully-Fisher measurements range from about 90 to 110 million light-years. So maybe going with an average of 100 million light-years is about right? While NGC 5963 is an interesting, very blue, galaxy I was really interested in NGC 5965.

NGC 5965 is a near edge-on spiral galaxy with a rather warped disk located about 160 million light-years away. Both redshift and Tully-Fisher measurements put it about this distance. The question is what warped its disk? It is surrounded by at least 9 dwarf galaxies with a similar redshift. Many are out of my field since I put it high in order to also capture NGC 5963. They differ little from those in the image but for CGCG 297-017 which is a distorted dwarf spiral. I can't fathom a dwarf of its size warping a much larger galaxy but suppose it might happen. Notice that the warped disk isn't the only distortion to the galaxy. "Above" the core region there are two curved brighter regions, looking almost like small curved horns in the galaxy's halo. I found nothing on either feature in the literature. They may just be star clouds in the disk of the galaxy but I doubt that. I'm wondering if the warped disk and these bright areas are due to a merger in the recent past with one or two dwarf companions. Pure speculation on my part but does seem to fit what I'm seeing.

NGC 5963 and NGC 5965 were discovered by William Herschel on May 5, 1788. They aren't in either of the H400 programs

There are several quasars in the image as well as several Ultraviolet Excess Sources which are likely quasars as well. UvES objects are determined photographically so don't have the spectral data to confirm them as quasars. Hence the classification based on their strong Uv emissions. One quasar is listed at only 2.5 billion light-years and appears to have a slight bit of fuzz around it. A couple catalogs list it as a galaxy though the Sloan survey calls it a quasar. I've given it both designations on the annotated image.

Two other NGC galaxies are in the image down in the lower left corner, NGC 5969 and NGC 5971. They were found by Lewis Swift on August 5, 1885.

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

Related Designations for NGC5963

NGC5964

NGC 5964/IC 4551 is a low surface brightness barred spiral with a bright bar but faint arms. To my eye, the bar is somewhat bowed rather than straight as most bars are. It is located in Serpens Caput about 73 million light-years distant by redshift and 87 million by the mean of other non-redshift measurements. NED classifies it as SB(rs)d with the possibility it has an AGN core. Seligman and the NGC Project say it is SBcd with no mention of a ring or the AGN. I can't see the ring either. Assuming the redshift indicated distance it is about 113,000 light-years across. Using the larger non-redshift distance it is almost 135,000 light-years in size. Either way, it is a large spiral.

The galaxy was discovered on April 24, 1830 by John Herschel (his dad missed it). That got it the NGC number. It was later seen by Lewis Swift on August 19, 1897. Since Swift's position in RA was only approximate it wasn't recognized to be the same galaxy so got an IC number. John Herschel's description of it is rather surprising. It reads: "vF, vL, R, vgbM, r, diam = 9s of time. With long attention it is seen to be composed of excessively minute stars like points rubbed out; and is, in fact, a globular cluster, but to see it thus requires long and perfect tranquility of the eye. A very interesting object." The first part reads "Very faint, very large, round, very gradually brighter middle, resolvable, diameter 9 seconds of time" 9 seconds of time would be a bit over 2 minutes of arc. It is over 5 minutes of arc across in my image. The surprising element is John Herschel thought he was resolving it as a globular cluster. Considering most of its brightness lies along the bar and is far from round I find this quite odd. It does have a lot of field stars across it, a few of which might have been right at his visual limit. I suppose resolving these might have made the impression of a barely resolved globular cluster and their light may combine to make it look spherical. The brightest is 15th magnitude with most 16th to 19th magnitude. I doubt he'd have seen more than two or three with his 475mm speculum mirror. I've never tried for this one visually though some observing notes were lost in the move.

Seeing was poor for my image. There are virtually no amateur images of it on the net that I could find, most of which are even worse but for one taken with a 20" scope that was mirror flipped making it hard for my brain to tolerate. So I'll have to be happy with it for now.

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

Related Designations for NGC5964

NGC5970

NGC 5970 is a nice spiral galaxy in Serpens Caput. It is classified by NED as SB(r)c; HII LINER. It is some 90 to 100 million light-years distant depending on the source. I measure it at about 76,000 light-years across its longest dimension. I used 92 million light-years for a distance as that was a distance that best fit the various distance I found weighting toward the modern when a date was available.

I put it on the list as it was in the second Herschel Observing Program. I've put all those I can reach on the to-do list with the better ones getting a higher priority. Why this one waited so long to be taken I don't know but it may never have been in position when the weather cooperated until now. William Herschel found it on March 15, 1784.

It is listed as having two companions in several sources but doesn't list them. If PGC 055664 to the northwest is one of them then it's not a companion being 5 times more distant. IC 1131 has a slightly larger redshift but close enough to be a true companion given the error bars in using cosmological redshift for a distance measurement. Most sources do consider it a companion. It was discovered by Stephane Javelle on June 29, 1891.

The rest of the field is rather typical but again limited by very poor transparency which cost me over one magnitude worth of faint fuzzies. One though caught my attention. It is the quasar at 0.411 light-years in the lower right corner. It's PSF doesn't fit that of nearby stars indicating it is a bit larger than a point source. Not by much so a local seeing glitch could be to blame but it also could be I'm barely seeing the galaxy housing it as well or at least part of its core. There were no asteroids in the imaging area that I picked up. The field is 30 degrees from the ecliptic so this isn't surprising.

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

Rick

Related Designations for NGC5970

NGC5972

As most know by now I like to go where most amateurs fear to tread. Back in the fall of 2008, it was announced that a Dutch school teacher, Hanny van Arkel, looking at Galaxy Zoo images saw something odd. Hundreds had looked at the same image before her but she was the only one to wonder "What's that?" and post the question. It turned out to be a green object outside the obscure galaxy, IC 2497. It was bright green though on the Sloan images it was blue. At the time it was a mystery. Fortunately, the moon was out of the sky and it was well placed so I gave it a try to see if I could pull it out. Digital imaging was still new to me and I wanted to test its limits. It turned out to be relatively easy, not a difficult test after all. Still, it became the first amateur image of it as far as I and Hanny could determine. A check of Google images fails to turn up an amateur image of it even now. Though it misses many posted to Flickr and the like. Still, it surprises me a unique but rather easily imaged object is so ignored by most amateur imagers. It was later determined to be a cloud of mostly ionized oxygen illuminated by a now faded QSO in the heart of the galaxy, possibly left over from something IC 2497 digested. Were there others? Galaxies devour their kind constantly so it seemed likely.

Back in April 2015, the HST group announced they had found similar objects lit by a few other galaxies now vanished quasars so it wasn't unique after all, just very rare. One of their discoveries, NGC 5972, was well placed in my sky in late May so I had to give it a try. Like Hanny's Voorwerp (voorwerp is Dutch for "object") these are green. Due to late May skies allowing me only time for one of my typical 100 minute image runs in dark skies I took one round of data on it. I expected more would be needed as this is much fainter than Hanny's Voorwerp. I was wrong. I may not have HST resolution but much of the green object is seen. Yet again it wasn't as difficult as I expected.

It is thought these are gas clouds lit by light echoes of long-faded quasars in the heart of these galaxies. I am guessing they are blue in the Sloan image because those include ultraviolet mapped to deep blue along with blue mapped to a lighter blue. This Uv light may be stronger than the green or blue causing the color shift. In my pure LRGB image, the green is the natural result even after I subtract green from airglow I have in my images. The green is apparently due to OIII shifted by cosmological redshift from its normal teal to green. The shift is too great to allow standard OIII filters to be used on these so I've not attempted that.

You can read more about these Voorwerpjes (Dutch for "objects") at http://www.skyandtelescope.com/astronomy-news/hubble-finds-ghosts-of-quasars-past-042215234/

Redshift puts the galaxy about 410 million light-years distant. HST data says a 40" filament is 75,000 light-years long at the distance to NGC 5972. That works out to a distance of just under 390 million light-years. A rather good agreement as these distances go. Using the HST distance I get a size of 166,000 light-years for the galaxy including the small puff of green just south of the galaxy. The galaxy was discovered by Édouard Stephan on June 29, 1880. It is listed as S0-a or S0/a depending on the source.

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

Related Designations for NGC5972

NGC5981

NGC 5981, NGC 5982 and NGC 5985, right to left, are usually known as the "Draco Triplet" though there are other triples in the constellation these are the brightest. This was a very early image when I had little skill in digital imaging as my 50 years of film work didn't prepare me well for this new mode. The quality of the image is very poor for the quality of the night it was taken. I didn't do research nor even have software to annotate an image. Fortunately, these three are all of major interest in the image.

They aren't as related as they appear to be. NGC 5985 is a barred spiral about 110 million light years away, NGC 5982 an E3 Elliptical galaxy about 130 million light years out and NGC 5981 is an edge on spiral, like NGC 5746 above but with the normal ball-shaped core region. It is the smallest in apparent size. That might make you think it the most distant but actually its the closest as about 80 million light years. Thus it is also, by far, the smallest of the three. Notice how much smaller it is than giant NGC 5746 above yet that galaxy is 25% farther away. Not much on the net of these guys but lots of photos by other amateurs.

NGC 5981 was found by George Stoney on May 6, 1850. The other two were found much earlier by William Herschel on May 25, 1788. NGC 5985 is in the second H400 program. NGC 5982 is in the original program. My notes from my entry on May 18, 1985 with my 10" f/5 on a humid night at 120x read: "Small, round galaxy with a bright core that's nearly but not quite starlike. It's large neighbor, NGC 5985, is more interesting so why isn't it in this program?" Guess it had to wait for the second version.

Being a very early image I didn't do any research on this one. I just wrote this for the web and will do a good version, with a much better image, as time allows.

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

Related Designations for NGC5981

NGC5987

Besides Arp galaxies on my to-do list, I have a bunch I call Arp wanna-be galaxies. They didn't make his list but could have. Sometimes they fit his categories, sometimes they need one of their own or fit his rather small miscellaneous class. This is one of the latter in my opinion.

NGC 5987 has a rather odd system of dust lanes. There's one that is nearly straight that runs across the bottom much like a similar one in M63. M63's lane leads to a dwarf galaxy west of the main part of M63 though real deep images show the galaxy going as far as the little dwarf which it may be devouring. The dust lane might have been caused by the dwarf. In the case of NGC 5987, there's no related dwarf that I can find. There's another linear dust lane that joins the long one and appears to head to the back side of the core. One linear lane is hard enough to explain, a second that joins it seems a real mystery. Yet I find nothing about this in the literature.

NGC 5987 is classed as an Sb spiral by NED and the NGC project. It is about 140 million light-years distant in the constellation of Draco. It was discovered by William Herschel on May 25, 1788. It isn't in either of the Herschel 400 programs.

As usual, there are many distant background galaxies. I've prepared an annotated image showing the Quasars (Q) and Galaxies (G) and their distance in billions of light-years. I have no idea why some galaxies have this data and others don't. Even more of a mystery are two spindle galaxies, both oriented north and south near the eastern edge. They are on opposite sides of a distant, faint, spherical galaxy at 4.4 billion light years. Yet these two much brighter galaxies not only don't have any redshift data, I couldn't find them in any catalog at NED or SIMBAD! I've identified them with a question mark. The bright blob on the bottom right of center is just a bright star I didn't know how to deal with years ago.

14" LX200R @ f/10, L=6x10' RGB=3x10x3', STL-11000XM, Paramount ME

Related Designations for NGC5987