NGC 6100 is a ring galaxy in eastern Serpens Caput just about on the celestial equator that is about 230 million light-years from our galaxy and 110,000 light-years across. It was discovered by Lewis Swift on July 3, 1886. He's likely more famous to amateur astronomers for his shared discovery of comet Swift-Tuttle that's responsible for the Perseid Meteor Shower each August. NGC 6100 has both an outer blue ring and an inner pseudo-ring. The area between these came out quite red in my image which surprised me. Oddly the Sloan image shows it more a muddy brown color. I'm not sure why the difference though Sloan picks up 4 bands beyond our visual range that often skews its color. A likely background galaxy is seen through the outer ring to the northeast (upper left). NED shows nothing at its position, another surprise. It's clearly a reddish galaxy that didn't make it into any catalog NED carries.
I was hoping to find something on this galaxy but I can't find any paper having ever discussed it other than to list it in a catalog. A second ring galaxy appears in my image to the far left edge nearly halfway between the center line and top of the image. It is listed simply as G 0.075 in the annotated image as it is only found in the IR source 2MASS catalog that uses only its coordinates for identification. It has a bright core surrounded by a very faint outer ring. Again the area between the two appears somewhat red in color.
Most galaxies in the field suffered the same fate as this one. That is, they are listed only in catalogs that use coordinates for identification, mostly 2MASS and/or Sloan catalogs. Those, as mentioned, are just labeled as G or Q for quasar. Some rather bright galaxies have no label as they too were only identified by coordinates but had no redshift or other distance data available at NED.
Seeing wasn't all that great the night this was taken. It started cloudy so I hadn't opened the roof to cool the scopes when it suddenly cleared. I took the 4 luminance frames right after opening and thanks to the scope not having come to temperature there were tube currents that made for wonky stars. That cleared up just as I started the color frames. Being faint I took twice my usual color data though one green was lost when a boater hit the observatory with a multi-million candle power spotlight looking for his marker buoy. The next night I took 4 more luminance frames planning on using those to replace the first series taken with the tube currents. But that night was of even poorer transparency and while the stars were good that series didn't go as faint. So I ended up processing both then combining them in lighten mode. That filled in the wonky stars to some extent without losing the fainter objects. Stars are still far from perfect but a lot better and the signal to noise ratio of the image somewhat improved as well.
14" LX200R @ f/10, L=8x10' RB=4x10' G=3x10', STL-11000XM, Paramount ME Related Designations for NGC6100NGC 6100, UGC 10307, CGCG 023-032, CGCG 1614.4+0056, MCG +00-41-012, 2MASX J16165235+0050284, 2MASS J16165237+0050287, GALEXASC J161652.49+005024.7 , GALEXMSC J161652.38+005026.5 , 2MIG 2223, NSA 146870, PGC 057706, UZC J161652.4+005028, NGC6100, | NGC6100L8X10RB4X10G3X10.JPG
NGC6100L8X10RB4X10G3X10CROP125.JPG
NGC6100L8X10RB4X10G3X10ID.JPG
| NGC 6106 is a rather ragged Sc spiral galaxy in southwestern Hercules about 70 to 75 million light-years away. It was discovered by William Herschel on April 13, 1784. It is in the second Herschel 400 observing program. The only other major galaxy in the frame is UGC 10337/PGC 057827. it is a rather red edge on Sb spiral.
There is what I see as a bright star about 5 seconds of arc southwest of the core. NED, however, claims it is is the galaxy NSA 166863. They give it a magnitude of about 13 which is correct and a size of 2.4x0.9 minutes which can't be right. They also give it a redshift of virtually zero which is to be expected for a star in our galaxy. The size and brightness are only slightly less than what they quote for NGC 6106. It appears somehow their automation decided that it was the core of NGC 6106 causing this confusion. In any case, it is a point source in my image and definitely a foreground star in our galaxy.
There are a lot of distant galaxies in the image out to 5 billion light-years and beyond. Two, if the redshift is correct, are the most distant individual galaxies I've imaged. One with a redshift of 1 which puts it at 7.78 billion light-years distant. But the real puzzler is north of it with a redshift of 2 and a distance of over 10 billion light-years. Further than any quasar in the image. I listed it with a question mark as I have a problem with my system seeing a galaxy at that distance, quasar yes. If it really is a galaxy then it is a humongous one. It is a bit diffuse in my image but that could mean it is a tight group of galaxies at that distance rather than one. I could pick up the combined light of a small cluster at that distance if the galaxies making it up are huge. NED labels this one as a verified spectroscopic redshift determination so I can't deny the distance. I'd love to know more about what that object is. NED identifies it as SDSS J161935.74+072831.3 if anyone wants to pursue this further.
14" LX200R @ f/10, L=4x10' RGB=2x10', STL-11000XM, Paramount ME
Related Designations for NGC6106NGC 6106, UGC 10328, CGCG 052-001, CGCG 1616.4+0732, MCG +01-41-016, 2MASX J16184720+0724396, 2MASS J16184717+0724393, SDSS J161847.16+072439.1, GALEXASC J161847.23+072438.6 , IRAS 16163+0731, IRAS F16163+0731, AKARI J1618470+072444, HIPASS J1618+07, HIR J1618+0725, PGC 057799, UZC J161847.2+072439, WVFSCC J161848+072329, WVFS J1618+0730, UGC 10337, CGCG 052-002, CGCG 1617.1+0724, MCG +01-42-001, 2MASX J16192862+0716435, 2MASS J16192860+0716435, SDSS J161928.60+071643.4, SDSS J161928.60+071643.5, GALEXASC J161928.62+071643.7 , ASK 424439.0, NSA 073456, PGC 057827, UZC J161928.6+071644, [TTL2012] 094365, NGC6106, UGC10337, | NGC6106L4X10RGB2X10ID.JPG
NGC6106L4X10RGB2X10R-CROP125.JPG
NGC6106L4X10RGB2X10R.JPG
| NGC 6118 is an SA(s)cd galaxy with some HII emission located in Serpens Caput about 4.2 degrees southeast of NGC 6070 in the previous post. Both are SAcd galaxies just that this one doesn't have the ring-like structure near its core. Also, the arms of NGC 6118 start at the core rather than from much further out in the disk as they do with NGC 6070. While only a bit over 4 degrees from NGC 6070 the area of this galaxy is very barren of background galaxies. Also, it is outside the area of the Sloan Survey as it has been picked up by NED. NGC 6118 is the only object in the field that NED had any redshift data for so I didn't prepare an annotated image. Only a half dozen other galaxies were even listed for this field all from the 2MASS and nearly all are very faint. This was taken a similar night as NGC 6070 so is also about 1.5 magnitudes dimmed by conditions which make the field seem even more barren than it really is.
Just off the image to the upper left is the B9V blue star HD 147550 at magnitude 6.32. It cast a nasty blue haze over the entire field thanks to all the haze in the air this night. I hope it didn't skew the color balance.
The galaxy was discovered by William Herschel on April 14, 1785. It is part of the original Herschel 400 observing program by the Astronomical League. My visual observation of it on May 18, 1985, on a night of poor transparency due to high humidity reads: "Large, elongated, galaxy seen only by averted vision. By far the most difficult object to date. Just southwest of a 6th magnitude field star not plotted on my Tiron. Probably much easier on a better night without the glare of the star due to the humidity." So it seems conditions have hit me again with this galaxy.
In fact, I tried to image this one soon after starting my digital imaging career after building this observatory. That one came out very poor due to the red and blue severely hurt by haze turning the entire image somewhat green as back then I didn't know how to cure that. I tried reprocessing it but the red data was just too weak and the bad conditions made the glare from the B9V star far worse so adding the data wasn't of any help either. While it could benefit from yet another try, two is where I stop on this one. If it was in an interesting field then I might have considered it but with nothing but the galaxy, this will have to do.
Due to the poor transparency, I took 6 luminance frames rather than my normal 4 but I don't think it helped much if any. Still, this one is a big improvement over the first try in 2007.
This is the first of only 5 images June's lousy weather and short nights allowed me. Half of what last year's weather allowed.
14" LX200R @ f/10, L=6x10' RGB=2x10', STL-11000XM, Paramount ME Related Designations for NGC6118NGC 6118, UGC 10350, CGCG 024-008, CGCG 1619.3-0210, MCG +00-42-002, 2MASX J16214862-0217003, 2MASS J16214843-0217023, 2MASS J16214861-0217003, SDSS J162148.62-021701.0, IRAS 16192-0210, IRAS F16191-0210, CGS 518, KIG 0736, 2MIG 2235, 6dF J1621485-021700, 6dF J1621486-021700, GSC 5038 00765, HIPASS J1621-02, NSA 146933, PGC 057924, LEDA 3157924, UZC J162148.5-021701, KIG 0736:[VOV2007] 135, NGC6118, | NGC6118L6X10RGB2X10R-CROP0125.JPG
NGC6118L6X10RGB2X10R.JPG
| I found this rather busy field quite interesting as it has 3 NGC galaxies and a very flat galaxy as well as some other rather strange galaxies. I was going to center on NGC 6120 but when I did a test shot for how to frame it for the to-do list the field was so interesting I had to move the center position to where i could pick up as many of the interesting galaxies as possible. The field is located in northeastern Corona Borealis not far from the famous Hercules Galaxy Cluster.
NGC 6120, my initial object, is a peculiar spiral that could have made Arp's Atlas in any of several categories. It has a heavy arm as well as a tidal arm. Arp put tidal arms into many different categories for some reason. Besides the heavy blue arm, its other arm is oddly red and very different looking. On it is an odd elongated blue object NED identifies as SDSS J161947.71+374627.6. With no redshift, it is hard to tell if it is related to NGC 6120 or not. It might be the remaining core of something it is digesting or a super bright star-forming region or a separate galaxy (NED lists it as a galaxy) that is or isn't related to NGC 6120. I found nothing to help decide this issue. The tidal arm is composed of several overlapping star clouds of various sizes so quite different from most tidal features. It points to NGC 6119 which has its own odd pulled out or tidal arm which doesn't point back to NGC 6120. Otherwise, it is a rather normal looking spiral. Have these two interacted in the past? I'd expect more distortion in 6119 if they had but that doesn't mean they didn't interact. Both have similar redshifts that put them 420 million light-years distant. Ignoring its tidal plumes NGC 6120 is about 77,000 light-years across though nearly 130,000 light-years across including the plumes that go to the south as well as the north. NGC 6119 is about 100,000 light-years across including its pulled out arm. NGC 6120 was discovered by William Herschel on March 17, 1787 but is not in either Herschel observing program. NGC 6119 was discovered by John Herschel 40 years later on April 27, 1827. I found nothing on its odd pulled out arm.
The third NGC galaxy is NGC 6122. It is seen edge-on and appears to be a "red and dead" spiral though that may just be due to seeing it on edge. That assumes it is an Sb galaxy as NED classifies it. Other sources sometimes classify it as S0. Since I see a faint dust lane I don't agree with the S0 classification. Its redshift puts it slightly more distant at 460 million light-years. This, however, may be just due to random motion within the group and it is really part of the NGC 6120 group. There are other mostly smaller galaxies in the 400 to 460 million light-year range in the image suggesting this might be a rather large group though I found no group listed at NED. NGC 6122 was discovered by Guillaume Bigourdan on May 6, 1886. It seems odd to me that John Herschel missed it as it has a higher surface brightness than NGC 6119.
My other galaxy of interest is FGC 2024 well to the south. It is a very thin edge-on galaxy that certainly has earned is position in the Flat Galaxy Catalog. It is strange in a couple of respects. First, the disk is highly warped to the southwest and seems to have a kink in its northeastern arm right where another galaxy SPRC 266 hides it from view. Its other oddity is the core. Look closely and you see it is tilted somewhat more to the north-south than the disk, even more tilt than the bent end of the southwestern arm. Does SPRC 226 have something to do with some or all of these odd features? I have no idea. SPRC is the Sloan Polar Ring Catalog. However, I don't see how this applies to this little galaxy. Both have similar redshift that puts them 910 million light-year distant. That distance makes FGC 2024 a very large galaxy some 325,000 light-years across. That's huge for any galaxy, especially an Scd spiral.
Another large galaxy likely part of the same group as FGC 2024 is ASK 306395.0 which is an E0 galaxy of some 250,000 light-years in diameter. I find the E0 classification rather odd as it appears quite elongated in my data. Part of that may be due to a small galaxy seen on its northeastern side. Another large spiral is seen near the lower left edge of my image, ASK 306272.0. It is rather unusual for me to resolve spiral structure in a galaxy some 2.27 billion light-years distant. It's nearly 200,000 light-year size makes this possible.
There are several galaxy clusters listed. The largest is centered at the very bottom of my image a bit right of center. It is listed as being medium compact with 80 members across a 25 minute diameter field. That should extend more than halfway up into my image but I see only two other galaxies at its 1.9 billion light-year distance in the image. I don't know where the others are hiding. Maybe the rather numerous ones at about 1.76 to 1.78 billion light-years are members.
For a field of such distant galaxies, it turns out to be quite interesting, at least to me. Due to my poor conditions here I was able to only get one frame for each color but it seems to have worked out. While there was a piece of space junk in the red frame it didn't go through anything so was rather easy to clone out. Thus I didn't try for more color data.
14" LX200R @ f/10, L=4x10' RGB=1x10', STL-11000XM, Paramount ME Related Designations for NGC6120NGC 6120, UGC 10343, KUG 1618+378, I Zw 141, CGCG 196-041, CGCG 1618.0+3754, CGPG 1618.0+3754, MCG +06-36-029, WISE J161948.07+374628.1, 2MASX J16194809+3746282, 2MASXi J1619480+374627, 2MASS J16194812+3746278, IRAS 16180+3753, IRAS F16180+3753, ISOSS 078, ISOSS J16197+3746, LDCE 1184 NED008, HDCE 0946 NED001, USGC U761 NED07, HOLM 739A, NSA 054155, PGC 057842, SSTSL2 J161948.04+374628.3, UZC J161948.1+374628, FIRST J161948.0+374628, NVSS J161948+374628, [M98j] 251 NED01, [SLK2004] 1229, [TTL2012] 088826, SDSS J161948.11+374627.7, [LHL2015] 1480, NGC 6119, KUG 1617+379, CGCG 196-040, CGCG 1617.9+3756, MCG +06-36-026, WISE J161941.98+374822.7, 2MASX J16194193+3748222, 2MASXi J1619419+374822, 2MASS J16194198+3748227, SDSS J161941.96+374822.6, SDSS J161941.97+374822.6, SDSS J161941.97+374822.7, GALEXASC J161941.84+374822.3 , GALEXMSC J161941.92+374822.1 , USGC U761 NED09, ASK 306419.0, NSA 166870, PGC 057837, SSTSL2 J161941.96+374822.9, UZC J161942.0+374823, NVSS J161941+374814, [BFW2006] J244.92486+37.80629 , Mr18:[BFW2006] 08308 NED05, Mr19:[BFW2006] 16973 NED03, [HIV2012] 1821, [HIV2012] 4382, [HIV2012] 5025, [HIV2012] 6108, ABELL 2199:[HIV2012] 0967, B2 1621+38:[HIV2012] 0840, UGCl 391:[HIV2012] 0394, UGCl 393:[HIV2012] 0280, [TTL2012] 088855, [LHL2015] 0692, NGC 6122, MCG +06-36-032, 2MFGC 13115, WISE J162009.57+374753.8, 2MASX J16200955+3747535, 2MASXi J1620095+374753, 2MASS J16200955+3747536, SDSS J162009.52+374753.5, SDSS J162009.53+374753.6, GALEXASC J162009.49+374754.2 , GALEXMSC J162009.53+374755.0 , LDCE 1184 NED009, HDCE 0946 NED002, ASK 306399.0, NPM1G +37.0511, NSA 054159, PGC 057858, [BFW2006] J245.03968+37.79820 , Mr19:[BFW2006] 17012 NED01, Mr20:[BFW2006] 27643 NED01, [GMM2009] 0818724, [HIV2012] 1818, [HIV2012] 4379, [HIV2012] 5022, [HIV2012] 6105, ABELL 2199:[HIV2012] 0964, B2 1621+38:[HIV2012] 0837, UGCl 391:[HIV2012] 0391, UGCl 393:[HIV2012] 0277, [TTL2012] 088836, [LHL2015] 1218, UGC 10346, FGC 2024, RFGC 3129, 2MASX J16200034+3735044, 2MASXi J1620003+373504, 2MASS J16200032+3735039, SDSS J162000.31+373503.7, SDSS J162000.48+373505.8, GALEXASC J162000.27+373505.6 , PGC 057854, [BFW2006] J245.00130+37.58436 , Mr20:[BFW2006] 27589 NED04, NGC6120, NGC6119, NGC6122, FGC2024, | NGC6120L4X10RGB1X10.JPG
NGC6120L4X10RGB1X10CROP150.JPG
NGC6120L4X10RGB1X10ID.JPG
| NGC 6140 is a spiral galaxy in Draco. Redshift puts it at 42 million light-years though non-redshift measurements range from 27 to 38 million light-years. It is a rather low surface brightness galaxy. This is a very early image when my processing was poor. I need to redo it. My processing hides the true difference between its brighter parts and the faint arms making the arms look much brighter than they really are. It was discovered by William Herschel on June 3, 1788. It isn't in either H400 program.
14" LX200R @ f/10, L=6x10' RG=2x10'x3, STL-11000XM, Paramount ME Related Designations for NGC6140NGC 6140, UGC 10359, CGCG 320-025, CGCG 1620.6+6530, MCG +11-20-012, 2MASX J16205816+6523259, 2MASXi J1620574+652327, IRAS 16206+6530, IRAS F16206+6530, ISOSS J16209+6523, 2MIG 2233, PGC 057886, UZC J162058.5+652326, [SLK2004] 1231, NGC6140, | NGC6140L6X10RGB2X10X3.jpg
| NGC 6155 is a barred spiral galaxy in Hercules classified as SBcd. NED's redshift measurement puts it about 110 million light-years distant but non-redshift measurements say it is only 83 million light-years away. The bar is barely visible in my cropped image at 0.8" per pixel running from the southeast to the northwest. Apparently, it stands out better in near IR bands.
What drew my attention to this one is that it appears sloshed. That is the nucleus is well off center. It is well centered in the blue spiral arms of the galaxy but both are well east of the outer rather featureless reddish halo. Apparently, the halo is poor in new stars, though the highly fragmented arms are quite blue indicating good star formation is going on there. It almost looks like a small spiral superimposed over a low surface brightness elliptical.
The galaxy was discovered by William Herschel on May 12, 1787 and is in the Herschel II program. He got the position a bit wrong. This was noted and corrected by Guillaume Bigourdan but the date or even the year is lost to history, at least I couldn't find it.
The field is devoid of companions for NGC 6155 but its appearance leads me to think it must have interacted, maybe devoured another galaxy at some time in its past.
Another galaxy that attracted my interest once I saw it in my processed image is ASK 115977.0 at a bit over 1 billion light-years. It is obviously a barred spiral with two faint, widely spaced arms coming off the ends of the bar. Most of the galaxies in the image are over one billion light-years distant though a bunch are also seen at about 760 million light-years. No asteroid came to the party, however.
When I went to process this one three months after it was taken, I discovered, somehow, I'd not taken any blue frames nor did I note this. I considered it done. With it fast fading into bad seeing low in the northwest and my trees over there I either had to wait until next year to get the data or take it with a bright, nearly full moon. I chose the latter. My background was 10x higher than normal so I used 4 frames to try and get a usable signal to noise ratio to balance the red and green frames. Actually, I took 8 but somehow I used the wrong coordinates at first and the galaxy was half out of the frame. So I had to retake them using the correct coordinates. By then the moon was higher and the galaxy lower so blue data is not what I wanted but rather than wait until next year I went with it anyway.
14" LX200R @ f/10, L=4x10' RG=2x10 B=4x10, STL-11000XM, Paramount ME Related Designations for NGC6155NGC 6155, UGC 10385, CGCG 251-018, CGCG 1624.7+4828, MCG +08-30-013, 2MASX J16260830+4822009, 2MASXi J1626084+482200, 2MASS J16260831+4822006, SDSS J162608.32+482200.4, SDSS J162608.33+482200.4, SDSS J162608.33+482200.5, GALEXASC J162608.23+482201.5 , GALEXMSC J162608.28+482201.1 , IRAS 16247+4828, IRAS F16247+4828, AKARI J1626080+482202, UNAM-KIAS 1459, ASK 115981.0, NSA 020725, PGC 058115, UZC J162608.4+482202, NVSS J162607+482207, [PVK2003] J246.53470+48.36680 , NGC6155, | NGC6155L4X10RG2X10B4X10.JPG
NGC6155L4X10RG2X10B4X10CROP125.JPG
NGC6155L4X10RG2X10B4X10ID.JPG
| NGC 6166 anchors the galaxy cluster Abell 2199 in western Hercules at about 410 million light-years. So why did it make my Arp-like list? If you dig into its core you find there are four objects in there. Or are they foreground objects or background ones seen right through the galaxy? Adding to the confusion, three of the four have redshift data which vary rather greatly. While NGC 6166 is listed with a redshift of about 413 million light years, component A has a redshift that puts it 422 million light-years distant, B 369 million and C 446 million. Seems hard to believe objects around the center of the galaxy could have such a wide variation in velocity. How was the 413 figure determined, an average? That is 408 if the pure mean is used. There is a 4th component D is not listed in NED though it is listed at the NGC Project. My image seems to show a 5th member south of B/D and north of C. I think I see it in the Sloan image as well. Likely is just a foreground star. Adding to the confusion, there are 4 galaxies carrying the NGC 6166 name labeled A through D that are unrelated to the core features A through D. These galaxies are identified by name in the annotated image.
NGC 6166 was discovered by William Herschel on May 30, 1791. It is in the second H400 program.
I normally list cluster members by catalog number in the annotated image but this one is so dense even listing just by redshift distance is difficult. Those few with NGC or other commonly used numbers are shown. There's an interesting blue object NW of NGC 6166 at a redshift determined distance of 5.3 billion light years. It's very unusual to see a blue object at this distance that isn't a quasar. This one is reported as an Ultraviolet Excess object by the Galex Uv orbiting observatory and as a galaxy by the Sloan Survey. Usually UvES objects are quasars but in this case, it appears it really is a very active blue galaxy that is amazingly bright. Compare it to the small cluster galaxy above it that is rather red. Hard to tell the blue one is 11 times further away.
Unlike most fields, nearly every obvious galaxy had a listed redshift. There were only a few exceptions. They were listed in NED, unlike the totally missing ones I often find, just had no redshift data. I left those blank. So when you see one with no redshift it isn't that I missed it, there was none to list. Since it didn't happen all that often this annotation is by far the most complex I've done. It took more than the hour or so most take. I hope this is the all time record. I'm not looking forward to another! All the labels made the compressed size of the image twice as large as normal.
NED says NGC 6166 is 1.9 minutes along its long dimension. This means it is about 225 million light-years in diameter. That's one huge galaxy. It is classed as a cD elliptical. Nearly everything around it is puny by comparison. While it is far larger than our Milky Way galaxy the others in the group is mostly smaller than our galaxy. The exception is UGC 10420 at a diameter of 150 million light-years. It is a barred spiral classed as SB(r)b.
Many of the cluster members are of about the same angular size as the far more distant galaxies in the image. Many of these cluster at about 1 billion light-years and other groups at 2.3 and 3.5 billion light-years. Quasars are scattered about the image ranging out past 10 billion light-years. These are hard to find among the vast number of cluster dwarf galaxies in the annotated image. I probably should have only annotated non-cluster galaxies.
14" LX200R @ f/10, L=4x10', RGB=2x10'x3, STL-11000XM, Paramount ME Related Designations for NGC6166NGC 6166, UGC 10409, VV 364, CGCG 224-039, CGCG 1626.9+3940, MCG +07-34-060, 3C 338, 4C +39.45, B2 1626+39, B3 1626+396, WBL 616-001, USGC U766 NED23, LQAC 247+039 003, HOLM 751A, PGC 058265, SA 2199-010, UZC J162838.5+393306, MG4 J162838+3933, 87GB 162654.7+393938, 87GB[BWE91] 1626+3939, [WB92] 1626+3939, NVSS J162838+393300, VLSS J1628.6+3933, 6C B162655.7+393934, EUVE J1628+39.5, CTA 072, DA 413, NRAO 0504, TXS 1626+396, CoNFIG 251, EF B1626+3939, GB2 1626+396, RGB J1628+395, WN J1628+3932, ABELL 2199:[RS72] 089, [VE75] CL 1627+39, ABELL 2199:[BO85] 001, [OWT88] 162655.37+393938.2, ABELL 2199:[ATS88] 12, ABELL 2199:[ZBO89] R3, ABELL 2199:[LGC91] 0164, ABELL 2199:[PL95] BCG, [M98j] 251 NED04, ABELL 2199:[CG99] 010, [JP2001] 162701+3941, [MO2001] J162838.5+393304.4, [LVO2003] J162837.7+393255, [LPP2009] 1626+396, [GBW2010] CoNFIG1 248, NGC6166, | NG6166L4X10RGB2X10X3-ID.JPG
NG6166L4X10RGB2X10X3-IDinset.jpg
NG6166L4X10RGB2X10X3.JPG
| NGC 6175 is a pair of interacting galaxies in the Abell 2197E(ast) galaxy cluster in western Hercules about 410 million light-years from earth. The cluster is centered on the huge elliptical galaxy NGC 6173.
It is rather ambiguous that the pair of galaxies making up NGC 6175 are interacting from images of it but the strong radio emissions make it quite evident the pair is interacting. Also, faint plumes can be seen south of the southern member. The western side of the northern member has an odd brightening separated from the rest of the galaxy by a faint dust lane which carries its own designation. I can't tell if it is a plume or not. As the object's hard to see as a separate object I didn't annotate it. It is [BFW2006] J247.48177+40.63115 for those wanting to look it up. The coordinates are in its name. I was surprised that there's little on this interacting pair. It was discovered by William Herschel on March 18, 1787 but isn't in either of the Herschel 400 observing lists.
The cD galaxy for the Abell cluster is NGC 6173 a huge shell elliptical galaxy. I had no idea of its size or shells before taking this image. If I had I'd have put a lot more time into it as they just barely show in my image. The obvious part of the galaxy measures some 94 arc seconds across translating to a size of 183,000 light-years. That's large but then the obvious shell beyond this measures 175 arc seconds across for a size of 340,000 light-years. But I see hints of a yet larger shell that extends past ASK 164838.0 to ASK 165386.0 to the northwest and about an equal distance to the southeast. That makes it some 320 arc seconds across and 620,000 light-years in diameter. I need to revisit this field with a much longer exposure time. It was discovered by William Herschel the same night as NGC 6175 and also is not on either of the Herschel 400 observing programs.
ASK 165386.0 has a plume so it may be interacting with NGC 6173. It lies at the same distance so could certainly have been distorted by it.
At the top of the frame is maybe NGC NGC 6174. Problem is which of three galaxies is it, if any. NED says it is the combination of two to the east sharing a common halo. The NGC project says it is the single galaxy to the west at the same declination. I've labeled both with a question mark after the NGC 6174 label. The discussion at the NGC Project is too long to include here nor can I directly link to it. Go to http://www.ngcicproject.org/dss/dss_n6100.asp then click on the NGC 6174 Data button and scroll down to the Historical Release Notes/Correction for NGC 6174 section.
The other NGC galaxy in the field is NGC 6180. NED says it is S0 while the NGC project says E?. It was discovered on June 23, 1876 by Jean Marie Édouard Stephan of Marseille Observatory using their 80cm reflector.
Since all of the cluster members reside within about 10% of 410 million light-years I didn't include distances for cluster members, just their catalog name using the shortest name possible to reduce the clutter annotating so many objects creates. Non-cluster objects with redshift information do show their distance in billions of light-years. Seeing was really moving the stars around the night I took this creating rather wonky stars. Yet another reason for retaking it next year. Seeing was so bad the three blue frames taken the first night were completely unusable as the stars were all over the place. I tried again the following night but only one of the two was usable leaving the image a bit blue starved. Yet a third reason to redo this one.
This is my first August image. While July was poor allowing me only 12 objects captured, August was even worse with only 8 captured even though nights were longer. If the weather this year is becoming the norm thanks to global warming, I'm going to have a lot more time for my other hobbies!
14" LX200R @ f/10, L=4x10' RG=2x10' B=1x10', STL-11000XM, Paramount ME Related Designations for NGC6175NGC 6175, UGC 10422, CGCG 224-050, CGCG 1628.3+4045, MCG +07-34-087, WBL 618-002, PGC 058362, FIRST J162958.0+403742, 18W 009, ABELL 2197:[DGP89] 0022/7JBL , [MO2001] J162957.9+403745.2, [MOL2003] J162957+403744, NGC 6173, UGC 10421, CGCG 224-049, CGCG 1628.1+4055, MCG +07-34-083, GIN 562, WISE J162944.90+404841.8, 2MASX J16294485+4048421, 2MASS J16294489+4048419, SDSS J162944.87+404841.9, SDSS J162944.88+404841.9, SDSS J162944.99+404841.7, WBL 618-001, LDCE 1190 NED020, HDCE 0952 NED001, CAN 065 NED01, USGC U766 NED11, ASK 165389.0, HOLM 753A, NSA 029682, PGC 058348, UZC J162944.9+404842, FIRST J162944.8+404841, NVSS J162944+404842, 18W 008, RX J1629.7+4048, 1RXS J162944.5+404843, CALIFA 840, 2XMM J162944.8+404842, 2XMMp J162944.8+404841, ABELL 2197:[DGP89] 1753/7JBL , ABELL 2197:[CBW93] A, ABELL 2197:[PL95] BCG, ABELL 2197:[BTM97] 1, [M98j] 252 NED02, [MO2001] J162944.9+404840.6, [BKH2005] 0816-184, [BFW2006] J247.43699+40.81165 , Mr18:[BFW2006] 04792 NED237, Mr19:[BFW2006] 09501 NED145, Mr20:[BFW2006] 16089 NED65, [GMM2009] 0395749, [HIV2012] 1280, [HIV2012] 5423, ABELL 2199:[HIV2012] 0426, B2 1621+38:[HIV2012] 0155, [TTL2012] 404956, SDSS J162944.91+404841.7, [DZ2015] 772-01, [LHL2015] 0207, NGC 6180, CGCG 224-058, CGCG 1628.9+4040, MCG +07-34-095, GIN 566, WISE J163033.90+403221.9, 2MASX J16303388+4032221, 2MASS J16303389+4032218, SDSS J163033.91+403221.9, SDSS J163033.92+403222.0, GALEXASC J163033.89+403221.3 , GALEXMSC J163033.99+403218.0 , WBL 618-007, LDCE 1190 NED024, HDCE 0952 NED004, CAN 065 NED05, USGC U766 NED06, ASK 164768.0, NSA 029415, PGC 058386, SSTSL2 J163033.90+403222.4, UZC J163033.9+403222, ABELL 2197:[DGP89] 0052/7JBL , ABELL 2199:[DGP89] 5507/9JTL , ABELL 2197:[CBW93] E, [BFW2006] J247.64130+40.53941 , Mr18:[BFW2006] 04792 NED272, Mr19:[BFW2006] 09501 NED169, Mr20:[BFW2006] 16089 NED81, [HIV2012] 0882, [HIV2012] 5273, ABELL 2199:[HIV2012] 0028, B2 1621+38:[HIV2012] 0005, [TTL2012] 403062, [DZ2015] 772-03, [LHL2015] 0231, NGC6175, NGC6173, NGC6180, SAFIRES J162958.45+403752.0, [PJY2015] 587729652348289124 , | NGC6175L4X10RG2X10B1X10ID.JPG
NGC6175L4X10RG2X10B1X10R.JPG
| NGC 6181 is a rather nice spiral nearly everyone, even the pros tend to ignore. When they do mention it they can't even agree as to its classification. NED says SA(rs)c (no bar) while in another section it says SAB(rs)c (it has a bar). Most of the internet sites covering it say SBc. That omits the inner ring. Seligman says SBc? What earns it the question mark I don't know but he sees a bar but not the inner ring. I can't see the ring either that NED sees. Bar's are not always seen in visible light so it may exist in other wavelengths. Or the elongated nucleus is taken for the bar.
What is covered to some extent is SN 1926B. It appeared in the edge of a blue nebula in the galaxy, likely a star cloud as it isn't strong in H alpha light from the one photo in H alpha I found of it. I assume their filter accommodates its 107 million light-year redshift. I've marked the cloud in the annotated image.
This galaxy is in Hercules and is about 110 million light-years distant by both redshift and non-non-redshift measurements. It's rare to see such a close agreement. It was discovered by William Herschel on April 28, 1788. It is in the second H400 observing program. That was one reason I had it on the to-do list but it was also a rather neat looking galaxy, something I'd not noted until last winter when I upped its importance level in my to-do list so it was finally taken Last May. Conditions were so bad that data was all unusable, it was taken again the next month even though by the time the weather allowed any imaging it was getting further from the meridian than I normally image. During the first red frame (and after one blue and one green frame conditions went bad, So bad the red frame and following blue and green frames were unusable. I was outside my T point map so had to guide and the guide star kept vanishing for several minutes at a time. Finally, the second red frame, while poor was sort of usable. I made it work but due to the far worse seeing for it there are some red flares to the northwest. I sort of dealt with them. Having only one red frame I had to clone out a bright satellite that went through the one usable red frame. That may have skewed the color of stars the brilliant satellite went over.
14" LX100R @ f/10, L=4x10' RGB=1x10', STL-11000XM, Paramount ME Related Designations for NGC6181NGC 6181, UGC 10439, CGCG 109-031, CGCG 1630.1+1956, MCG +03-42-020, GIN 798, 2MASX J16322096+1949357, 2MASXi J1632209+194935, 2MASS J16322095+1949351, SDSS J163220.95+194935.0, IRAS 16301+1955, IRAS F16301+1955, AKARI J1632211+194932, LDCE 1193 NED003, HIPASS J1632+19, NSA 147100, PGC 058470, UZC J163221.0+194934, 87GB 163012.4+195626, 87GB[BWE91] 1630+1956, NVSS J163221+194931, [RHM2006] SFGs 050, NGC6181, | NGC6181L4X10RGB1X10.JPG
NGC6181L4X10RGB1X10CROP125.JPG
NGC6181L4X10RGB1X10ID.JPG
| NGC 6207 is a much imaged galaxy but almost always because it is in the same field with M13 the rather famous globular cluster to its south southwest. It was on my to-do list as an object in the original Herschel 400 observing program. It was discovered by William Herschel on May 16, 1787. My comments from April 20, 1985 at 120x under fair skies (humidity reduced transparency) with my 10" f/5 are rather sparse reading "Small, oval galaxy, evenly bright. No nucleus seen." That's it. Apparently I wasn't impressed. My image shows a very obvious star near its nucleus. It appears to be about magnitude 13.5 yet I didn't mention it. I assume transparency was worse than I realized that night. It certainly is far brighter than the actual core to the south. So at least I was right that no core was seen. It's not obvious even in my image.
NED classifies it as SA(s)c with HII emission while the NGC Project says S... and Seligman says Sc?. Arm structure is certainly ill defined visually. References to IR images indicate the pattern may be stronger at that wavelength. One paper considers it an isolated spiral galaxy. It references 5 dwarf companions. These are labeled A-E in the annotated image. The paper is at: http://www.aanda.org/articles/aa/pdf/2008/32/aa09666-08.pdf and includes an IR image showing the spiral pattern a bit better than my image. The field stars are greatly suppressed in IR helping to show what it is hiding.
Distance to this galaxy is a bit of a puzzle. Many web pages say 30 million light-years but none give a reference. NED's redshift says 40 million while non redshift measurements there say about 62 million. So a two times difference. Also the paper mentioned above gives a size as 3 arc minutes. Even using their image I can't see it that large. I get about 2.7 arc minutes. Both on my image and theirs. Maybe they rounded. Using that I get a size of 23,600, 31,400 and 48,700 light-years. Flip that 3 sided coin. Though if the smaller sizes are right those dwarf galaxies are really super dwarfs. Dwarf E I measure at 5 arc seconds which is about 1,500 light-years at the 62 million light-year distance. These are tiny galaxies if the paper is right that they are part of the NGC 6207 system.
The other "major" galaxy usually captured in M13 images is IC 4617 an Sbc spiral according to NED and Sbc? by Seligman. It was discovered by Edward Barnard of dark nebulae fame. I can't find a date for its discovery however. This identification is a bit suspect. Barnard's position, and he was usually very accurate, has nothing but some of M13's stars. This galaxy is almost 1 minute further east and correct in declination. Thus most feel it is the galaxy Barnard found. Even Barnard could get something wrong it would seem. Though Barnard's notes appear to be missing so it could be Dreyer who got the position wrong. I agree with Seligman's length of 45 arc seconds which if the distance of 490 million light-years is correct works out to be a length of 107,000 light-years. Thus while it appears much smaller than NGC 6207 it is really much larger.
There are 3 proven quasars in the field and another 5 likely quasars. The latter are listed as UvES in the annotated image. Arp tried to link fields with lots of galaxies to active galaxies. Since NGC 6207 is not very active at all but for a few HII regions common to many spiral galaxies I wonder how he'd have explained all these quasars. No matter how many such fields were pointed out to him he stuck to his ideas they were ejected from active galaxies and their great redshifts were unrelated to the expansion of the universe but depended on how long it had been since they were ejected. I don't pretend to understand his logic.
I was initially fooled by a galaxy on the western edge of my image ASK 256119. On my FITS images it appeared just like a typical asteroid trail but for being a bit dimmer at either end. I put that down to conditions where weren't all that great for transparency. But turns out the Minor Planet Center shows no asteroids in the field. The galaxy would appear to be a candidate for the Flat Galaxy Catalog but is too faint? It certainly has no significant central bulge.
The stars in the lower right of my image are on the outskirts of M13. That's why there's a sudden increase in stars in that part of the image.
14" LX200R @ f/10, L=4x10' RGB=2x10', STL-11000XM, Paramount ME Related Designations for NGC6207NGC 6207, UGC 10521, KUG 1641+369, CGCG 197-007, CGCG 1641.3+3655, MCG +06-37-007, 2MASX J16430375+3649567, 2MASXi J1643037+364956, 2MASS J16430371+3649559, SDSS J164303.66+364955.7, IRAS 16412+3655, IRAS F16412+3655, KIG 0766, NSA 147222, PGC 058827, UZC J164304.0+364957, IC 4617, 2MASX J16420807+3641025, 2MASXi J1642080+364102, 2MASS J16420808+3641026, SDSS J164208.06+364102.6, SDSS J164208.06+364102.7, UNAM-KIAS 1479, ASK 256136.0, NSA 046415, LEDA 2085077, [SUV2010] 293, [HIV2012] 1865, ABELL 2199:[HIV2012] 1011, [TTL2012] 431917, NGC6207, IC4617, | NGC6207L4X10RGB2X10.JPG
NGC6207L4X10RGB2X10CROP150.JPG
NGC6207L4X10RGB2X10ID.JPG
|