NGC5591

NGC 5591 is a double galaxy in Bootes about 540 million light-years away. The galaxies appear to be making their first encounter. Whether their velocities are such they will merge I've not found. Come back in a 100 million years and we should have a good answer to this. The western component is listed at NED as Sdm pec with a starburst nucleus. In this case, the starburst activity appears related to their interaction. The eastern component is classed as simply Sc. The NGC project takes the approach that this is one strongly disrupted galaxy classed as Sc pec. To me, it is quite obvious these are two galaxies rather than one disrupted one. I doubt they looked anything like what we see today before the encounter began. It was found by Lewis Swift on June 4, 1886.

The other major galaxy in the image is the ordinary NGC 5587 at the top of the image. It is classed as S0/a by both NED and the NGC project. With the faint but obvious dust lanes, I have trouble with the S0 classification. It seems a rather old spiral in which star formation is dying down though the outer parts still show blue stars. It is much closer than NGC 5591 and not at all related to it. Redshift puts it at about 110 million light-years. It was found by William Herschel on April 17, 1784. It's not in either H400 program.

The field has little else of interest. The field galaxies are mostly all more than 1 billion light-years distant with some much more distant. The few quasars are also unusually distant.

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

Related Designations for NGC5591

NGC5600

NGC 5600 is a peculiar face on spiral galaxy in southern Bootes. Its distance by redshift is about 120 million light-years. However, there's no agreement on its distance by various Tully-Fisher measurements. They range from 110 to 350 million light-years with an average of about 230 million. Why this severe disagreement I was unable to discover. Assuming the redshift distance it is a bit less than 50,000 light-years across. Its structure is very weird. The CGCG says: "Blue, post-eruptive Sc with one pronounced spiral arm and several blue knots." I think I see two arms that sort of merge with one much fainter giving the one arm illusion. The bright blue knot directly west of the core in line with my label in the annotated image is listed by NED as a separate galaxy. But they give it virtually the same redshift as the galaxy making it just a star cloud though I suppose some could argue it is the core of something it is eating and that may account for its odd structure. Its strong blue color argues against this, however. It was discovered by William Herschel on April 17, 1784, and is in the second Herschel 400 observing program.

To the east of NGC 5600 is a faint, somewhat curved blue object. I find no distance data for it and in fact but for catalog entries (GALEX for RV and AGC for radio) I find nothing on it. The curve is partly real and partly an illusion. The latter is due to a star to the southwest on the edge of the object that makes the southern part appear to curve more than it really does. I assume it is a blue irregular galaxy of some sort. The problem comes when I tried to pin down its position. SIMBAD identifies it both under its Sloan positional ID and the radio AGC one giving the same position, 14h 24m 14.881s +14d 39m 11.73s. NED, however, separates the optical and radio positions giving 14h 24m 14.9s +14d 39 17s for the optical GALEX position and 14h 24m 14.8s +14d 38m 58s for the AGC 248933 position. That puts the radio southwest of the visual object by about 24 seconds of arc. However, the error bar for the radio position is 45" So SIMBAD says the two are the same while NED says they may be the same or different. I went with SIMBAD on the annotated image. I'd love to know exactly what this object is and why it is a good radio source if it is the radio source.

My notes indicate I had taken this one several years ago. However, I can't find the files any place. So I ended up retaking it before it got too far west this year. To do that meant taking it with a half-moon nearby. Something I try to avoid. That also put it further west than my Tpoint map so I had to guide this one. Something I rarely do but it worked out well anyway. It got so low for the color data two of the three color frames were out of alignment with the luminance and red frames. This forced me to break out RegiStar to whip them back into alignment which changed by several pixels across the face of the image. More than I can ever recall happening before but it was a very humid night. Could that cause more dispersion than normal low in the west? Thanks to the moon the image doesn't go as deep as normal and color data is noisy and weak for fainter objects. I had to invent a new technique to pull color into these regions. It worked so well I will add it into my normal process flow as it added little time and really works well for faint objects that really need more time than I usually give color data.

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

Related Designations for NGC5600

NGC5614

This is a reshoot with twice the exposure time under a bit better seeing. It didn't pick up much more of the plumes than the first but detail in the galaxy is far better. Some of the text below is from the initial post but there is something new in this image so keep reading as it is near the end. It is not in the original nor is it an asteroid or another solar system object.

Arp 178 consists of three galaxies NGC 5613 (upper), NGC 5614 (lower) and NGC 5615 (inside NW halo of NGC 5614). These are located in the constellation of Bootes. NGC 5613 is nearly 400 million light-years distant while the other two are a bit less than 190 million light-years away. Arp put these in his category of galaxies with narrow counter tails. His comment reads: "Ring off center, broad ejected plume from condensation in ring."

Most papers of the era of Arp's Atlas and prior consider NGC 5614 as interacting with the northern galaxy (5613). We now know that with 5613 having over twice the redshift this isn't the case. It is unrelated but worthy of its own entry in the atlas. It is classed as (R)SAB(r)0+ by NED and the NGC project agrees but leaves off the + sign. At first glance, it appears to have a faint outer ring. But look closely and you see it is really two very extended spiral arms that nearly overlap. One starts at the 11 o'clock position and goes around to the 4 o'clock position. The other starts at 5 o'clock and goes around to the 10 o'clock position. In both cases, the ends are further from the core than the other arm inside it. This may be easier to see in the Sloan image stretched a bit differently than my image. What caused this? There seems no likely source. Prior to its redshift being determined, it is easy to conclude that NGC 5614 caused it. Now it is a puzzle.

The main feature here is NGC 5614 a very large tightly wound spiral with an off-center core and huge plume. NED and the NGC Project classes it as SA(r)ab pec. The plume seems possibly related to NGC 5615. It certainly is due to a gravitational interaction in the recent past. The off-center core causes Arp's "ring off center" comment. At first, I thought it might be that this was a case of a merger with inner arms rotating counterclockwise and outer ones turning clockwise but I found a rotation curve that says all are rotating the same way. It is just the core being off center from the first ring that creates this illusion. I am having a hard time seeing it. Still, I believe it a merger in progress with NGC 5615.

The condensation Arp refers to is NGC 5615 and has a redshift that puts it about 3 million light years more distant than NGC 5614. NGC 5615 is not classified at NED, NGC project says S? I can't see enough to try classifying it so have to agree with NED. Is NGC 5614 in the process of digesting NGC 5615. I saw suggestions of this in early papers but nothing conclusive. One paper suggests that the tightly wound arms of NGC 5614 might be due to an unusually massive black hole at its core. No reason was given other than it appears such galaxies tend to have larger than expected black holes when this has been measured. Pretty speculative to me. In any case, it is an interesting galaxy as is NGC 5613.

After I wrote this Adam Block posted an image of this galaxy taken by the 32" scope at the Mt. Lemmon Sky Center observatories. It clearly shows NGC 5615 is broken into several bright cores. It also shows the bright blue arcs in NGC 5614 far more clearly. I now think 5614 is quite likely the remains of a galaxy torn asunder by 5615, even the core of it is being ripped apart by tidal forces. I wrote Adam with this suggestion and he agreed it is likely the case. The three million light-year difference in redshift is likely due to relative motion and difficulty of assigning a redshift based distance to a mess like this.

Another galaxy at about the same distance of NGC 5514-5 is to their NE. Several galaxies of the same distance as NGC 5513 are in the frame. It appears they are two different groups. Several galaxies at 1 billion light-years are also found around the image. While several more are at 2.1 to 2.2 million light years and may make a third group.

Normally I think of NGC galaxies as being closer than say a half billion light-years, far closer in many cases. But NGC 5609 at 1.31 billion light-years is an exception. NED lists its green magnitude as 16.3 while the NGC Project puts its visual magnitude at 15.7. Since green is usually used for this I can't explain the difference. Still, this one should be visible in larger amateur telescopes from a dark site, say a 16" or larger. Young eyes may glimpse it with less aperture if the brighter magnitude is correct.

The smudge of a galaxy north-northeast of Arp 178 is SDSS J142418.67+245549.8. NED says it is only about 6" of arc across though it is about 24" across in my image. NED also gives it a far too faint magnitude. It has no redshift data. Except that its position exactly matches that of NED I'd think they were talking about a different galaxy.

Southeast of Arp 178, below a galaxy at 2.2 billion light-years is an object marked by a question mark. NED lists it at 22nd magnitude. Indeed it is 22nd magnitude (barely visible) on my first image of this field but it is 19.5 magnitude on this image or 10 times brighter than that in my first image. There is a galaxy at that position. That got me wondering if a supernova had been seen at that position. Yep, it is PTF11dwn. PTF stands for Palomar Transient Factory. 11 is the year (apparently they don't worry about 2100 and beyond). The supernova is a type 1A at magnitude 19.5. It is in SDSS J142422.29+344833.8. It was discovered on May 23rd. My independent discovery image was taken on June 5th, 13 days later. I wonder how many others like this are lurking on my images I'll never know about since I have no comparison image. Only because it was near a galaxy I was annotating did I notice it. When comparing the NED image of the field that extra star in my image confused me for a bit. Otherwise, I'd never have noticed it.

Arp's image
http://nedwww.ipac.caltech.edu/level5/Arp/Figures/big_arp178.jpeg

Adam Block's image with the 32" telescope at the Mt. Lemmon Sky Center
http://www.caelumobservatory.com/gallery/n5613.shtml

Sloan image:
http://www.spacebanter.com/attachment.php?attachmentid=3518&d=1304625417

14" LX200R @ f/10, L=8x10' RGB=2x10'x3, STL-11000XM, Paramount ME

Related Designations for NGC5614

NGC5619

The WBL507 group of 4 galaxies is located in northwestern Virgo almost 400 million light-years from us. Three of the members are obvious; NGC 5919, NGC 5919B and NGC 5919C (NGC 5919 is also known as NGC 5919A). I just don't know which of many other galaxies at this distance in the image is the fourth. Other catalogs say the group has 8 members (USGC U625), 10 members (Mr19:[BFW2006] 04483) and 14 for Mr18:[BFW2006] 02293. Seems to be a define your own group field. While well removed from the first three I'll just say CGCG 047-055 makes a good choice for the 4th member. At least these 4 show signs of possible interaction. NGC 5619 has an odd inner red arm and a very oval ring of blue arms coming off the bar. Otherwise, it is rather low in surface brightness for such a large galaxy. NGC 5619B and C are narrow line active galactic nuclei galaxies. While not a certain sign of interact this is often the case with such galaxies. NGC 5619C also meets Seyfert 2 spectral specs also another indication of possible prior interaction. I can't find much on CGCG 047-055 though it is obviously highly distorted with much of the southern half of the galaxy appearing missing. NGC 5619 is a huge spiral. If the redshift distance is right it is nearly 250,000 light-years across, nearly twice the size of the Milky Way and our galaxy is an unusually big spiral at half that size. NGC 5919B and C are our size at about 115,000 light-years across. They look rather dinky compared to NGC 5619. CGCG 047-055 is "only" about 75,000 light-years across though that is about average for a spiral. NGC 5619 was found by John Herschel on April 10, 1828

The field is one that has been studied to find faint emission line galaxies. Most are around 22nd magnitude so very faint. You may need to enlarge the image to see some of the fainter ones. I have to question the redshift values of a couple in the image. One south of NGC 5619 and southwest of the very red M8 star has a redshift that puts it only 28 million light-years away. Yet its size is hardly larger than a very large globular cluster. Toward the left edge of the image near the bottom and just below a bright white star is one with a redshift that puts it 8.56 billion light-years distant. That means it is as bright as many quasars yet doesn't appear to be classed as one and certainly its spectrum has been studied to allow them to determine it is an ELG. Or did someone screw up the redshift measurements of these two?

There's one asteroid in the upper left quadrant of the image. Several other galaxies about the same redshift as NGC 5619 are seen in the image. Many more are just outside the bounds of my image.

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

Related Designations for NGC5619

NGC5638

These two NGC galaxies are located in northeastern Virgo about 90 million light-years away. At one time there was some disagreement as to whether these two were interacting. Now it has been pretty well decided they aren't interacting. I certainly see no indication of it. Both were discovered by William Herschel on April 30, 1786. Only NGC 5638 is in the second Herschel 400 observing program. NGC 5636 appears too faint for the program. Unfortunately, my notes from that got lost in the move to Minnesota. I can't recall if I saw NGC 5636 or not. NGC 5636 is a barred spiral while NGC 5638 a classic elliptical. Both are rather red and dead. I see some hint of new stars in NGC 5636 but not many. Something seems to have killed most star formation in this galaxy.

The field has three other rather major galaxies, UGC 09310 to the east is very blue and about the same distance as the two NGC galaxies. So why does it still have star formation while the other two have little star formation? I found no indication it has interacted with either of the NGC galaxies but it sure is distorted as if something nailed it in the recent past.

The other two galaxies are UGC 09277 and UGC 09285. The former shows little sign of current star formation. The latter has some blue stars indicating star formation, while weak today was common a billion years ago or so. UGC 09277 is half the distance of the other galaxies while UGC 09285 seems to be part of the same group as the other larger galaxies.

While I call these "major" galaxies that is only because they stand out in the image. None are really large, even the elliptical. Assuming they are at about 90 million light-years I measure them at:

NGC 5638 67,000 light-years
NGC 5636 37,000 light-years
UGC 9310 52,000 light-years
UGC 9285 36,000 light-years
UGC 9277 19,000 light-years using a distance of 40 million light-years.

The field has several other odd galaxies. Southeast of UGC 09277 is the blue smudge of SHOC 466. That catalog is the SDSS HII galaxies with Oxygen abundances Catalog. Then there's the ELG (Emission Line Galaxy) north of UGC 9310. NED puts it at a distance of over 6 billion light-years yet on a rather poor night for transparency I picked it up. That I can do that on a rather poor night seems impossible. I wonder if it isn't a veiled quasar or another such galaxy such as a BL Lac object.

To the southeast of the ELG is ASK 100527.0. It is a very large spiral at 145,000 light-years in size. It also has a surprisingly bright core region. That is red but the two arms are blue. Another large and even more distant galaxy is in the northeastern corner of the image. NED shows it at 4.33 billion light-years. Since that was determined photographically with filters rather than spectroscopically the distance is somewhat questionable. If right it too is very large at 150,000 light-years in size. The entire galaxy appears to be blue. It must really be very blue to survive reddening at that distance.

One asteroid put in an appearance. See the annotated image for details.

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

Related Designations for NGC5638

NGC5668

NGC 5668 is a nice nearly face on spiral galaxy in Virgo. It is well studied by the pros with over one hundred recent papers including it. Yet I was shocked to find not one amateur image of it on any forum I checked and only a half dozen or so amateur images on websites I looked at or Google turned up.

It is classified as an SA(s)d galaxy a bit over 80 million light-years distant. Several papers say it has a young short (about 12 arc second bar) though that isn't in any classification for it that I saw. It appears to have a lot of current star formation going on throughout the galaxy though much of its disk is surprisingly fain but for its arms.

NGC 5668 was discovered by William Herschel on April 17, 1789. It is in the second Herschel 400 observing program so shouldn't be totally lost to at least visual amateur astronomers.

NED lists a blue object to the east-northeast of its core as a separate galaxy. I've noted it in the annotated image. I have trouble with this as it looks like a star cloud in the galaxy in my image and the Sloan image I checked. Redshift puts it at a similar distance though I suppose it could be the remains of its last galactic meal.

NED listed several hundred objects, mostly galaxies and quasar or quasar candidates in the image. I couldn't begin to annotate them all without the image being a mass of labels. So I mostly limited my annotation to brighter objects but for a few very distant objects NED said were galaxies but are so distant I have to wonder how I picked them up as this wasn't a great night for transparency. For example, there's an Emission Line Galaxy (ELG) just southeast of NGC 5668 that NED puts at 8.38 billion light-years. I can't imagine even with great transparency I could pick up any galaxy in 40 minutes of luminance data at that distance. I've added (Q?) to its label as I have to wonder if it is not a quasar or a veiled quasar (one in which the galaxy's dust mostly hides the quasar at its core) rather than just a galaxy with emission lines.

I found a surprising number of quasars and quasar candidates in the image. While I annotated only a few of the fainter galaxies and emission-line galaxies I did include all NED indicated are or likely are quasars.

One asteroid put in an appearance. Two others were just out of the frame at the bottom.

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

Related Designations for NGC5668

NGC5673

As you should know by now I'm fascinated by flat galaxies, those with little to no central bulge. The Flat Galaxy Catalog contains the strictest rules for what it considers as flat. Less strict is the 2-micron survey's flat galaxy catalog. I search both for good targets. When the 2MFGC came up with 2 in the same field and they were big and bright NGC and IC galaxies I had to put that field on my to-do list. When I took the field I centered on the bigger and brighter of the two assuming it was the NGC galaxy and gave that name to the field. The Sky working with CCDSoft names the subs with the central object. I was more than a little surprised when it came up with that being the IC galaxy. I was sure it had screwed up. Turns out it did and it didn't. I'll save the complications for later. But it is true the IC galaxy is the bigger and brighter of the two so I'll start there since it is front and center.

IC 1029 is a surprisingly big and bright galaxy in the IC catalog and a rather classic rather edge-on spiral classified SAb: by NED and Sb?? by the Seligman. It was "discovered" by Guillaume Bigourdan on June 14, 1887 and lies some 110 million light-years distant by redshift and 140 million light-years away by other measurements. While in the 2MFGC I see some central bulge to it, more than I expected for a galaxy in this catalog. Apparently, its length was great enough to overcome the bulge as far as the catalog's criteria require. It is 95,000 to 120,000 light-years across depending on which of several distances you assume is correct. I'm favoring the larger distance and size for reasons I'll get to shortly.

While sources give credit for finding to Bigourdan it really was first seen by William Herschel. But due to an error by John Herschel that finding was ascribed by Dreyer to the wrong galaxy. That brings us to NGC 5673 that is officially discovered by William Herschel on May 15, 1787 but was never seen by Herschel who was really looking at IC 1029. Oddly John Herschel must have seen both but ascribed this one to his dad in error. He must have seen the IC galaxy long before Bigourdan yet never gets the credit for its discovery some reason I can't find other than he never seems to mention it but in passing being more concerned with "correcting" his dad's error that wasn't an error. For more on this mix-up see the write up for NGC 5673 in the NGC Project. Edit: Since I wrote this the NGC project went down. It is now partly up and keeps saying it will return but nothing more has happened for over a year. Once up again, if it happens, then you can check it out. For now see Steve Gottlieb's pages on the NGC and IC at: http://www.astronomy-mall.com/Adventures.In.Deep.Space/steve.ngc.htm

Due to this mix up its difficult to put a discoverer on these two. I'm going to say IC 1029 was really first seen by Herschel. Since the date of his entry some say is IC 1029 but he likely couldn't see is May 15, 1787. IC 1029 was likely discovered by Guillaume, Bigourdan on June 14, 1887. Most sources, however, stick with the reverse that couldn't have happened.

NGC 5673 is a much lower surface brightness spiral and bluer than its companion. Its core appears flatter to me. NED and Seligman classify it as SBc? and SBc respectively while the NGC project says Sc (no bar). I can't say I see one but they are so hard to detect visually in near edge on galaxies I'm not going to take sides here. Its distance is 100 million light-years by redshift and 130 million by other means. Note the difference between the two measurements for these to galaxies is similar. Makes me think they are related having the same motion through space in our direction reducing their true distance. Hence I'm going with the non-redshift distances here as being more likely correct. I measure its size as 72,000 to 93,000 light-years across.

There turned out to be a third 2MFGC galaxy in the image about 5 times more distant to the lower right in my image. I can't say it appears all that flat to my eye but my resolution isn't all that great either.

There are quite a few galaxies at about 950 million light-years scattered all over the field. More are on the right side than left. Though the biggest is LEDA 2352876 in the lower left. Beyond it is a very low surface brightness blue galaxy without any redshift data and only an SDSS position that I could find. It looks rather interesting but would need a lot of time to bring out its details due to its very low surface brightness. Even the core appears blue, just not nearly as blue as the rest of the galaxy. Wish I knew something about its distance.

Arp made a big deal out of fields around disturbed active looking galaxies that had quasars around them. He even developed a theory that quasars were nearby objects ejected from such galaxies and their redshift increased with their age. Really off the wall stuff that required new physics to support it. Right on the edge of crackpot but never going over the brink. But here is a field with two rather ordinary galaxies with lots of quasars around them. Several more are just off the top of my image. I wonder how he'd have dealt with this field.

This image hit severely by an aurora. The aurora was dying down when I took a prior image but then came back to life in the middle of this one. Not as strong but strong enough to greatly hinder my signal to noise ratio. This again forced me to over-process the background to remove all the color noise the aurora added to the image. Due to how strong it was in red and green I'm not all that sure of my color balance. I had to do a lot of correcting I normally avoid. Though all color correction as applied globally I'm hoping it is fairly accurate as I don't think the aurora would be all that different across my very small field of view.

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

Related Designations for NGC5673

NGC5674

Back in 2010, I imaged Arp 274 though didn't get it processed until May of 2011. I centered on Arp 274 not realizing a companion to these was just outside the field of view and actually more interesting. This image rectifies that omission by framing the field as I should have back in 2011. It also corrects a few mistakes I made in the original post and its annotated image.

Arp 274 is a galaxy triplet though Arp seems most interested in the two on the left saying the little galaxy has perturbed the eastern arm of the big galaxy. The middle galaxy's eastern arm does have a bulge that points to the little galaxy but from what we now know of galaxy interactions that isn't the type of distortion we'd expect from an interaction. Redshift data now indicates the middle galaxy is likely 40 to 50 million light-years beyond the other two. While NED had no redshift on the little galaxy on the east several papers do show a measured redshift that's almost identical to the western galaxy and nearly 1000 kps different from the center one showing they are unlikely true companions. The middle galaxy apparently is just a background galaxy photobombing the other two. Hence a nice field but otherwise uninteresting. The HST has more on this at: http://www.spacetelescope.org/images/ann0904a/ .

For this image, NGC 5674 was my primary target. It is really strange. The inner core region looks much like the many "Saturn-like" galaxies I've imaged but the southern ansa has an arm coming off it that bends up to the north and west to either join or possibly become a huge ring that nearly encircles the Saturn-like core. Much like NGC 1954 I posted last just, it seems made up of parts taken from two very different galaxies.

This field is located in northwestern Virgo. The two probably related galaxies in Arp 274 and NGC 5674 are about 360 million light-years distant. This means NGC 5674 is a very large galaxy with a diameter of about 140,000 light-years including the plume on the northeastern side. The western spiral of Arp 274 is a bit over 100,000 light-years across assuming the north pointing blob between the two large galaxies is part of the western one. The central one is about 110,000 light-years across assuming it is 400 million light-years distant. It is obviously a more massive galaxy than the western one but its arms are less pulled out giving it a slightly smaller angular length even though its bulk makes it seem much larger than it measures. The dinky third member is less than 30,000 light-years across.

NGC 5674 was discovered by William Herschel on May 12, 1793 but is not on either Herschel 400 list. NGC 5679 was also found by William Herschel but not the same night. It was discovered months earlier on February 12, 1793. It is certain he found the center galaxy but I can't say if he saw the western galaxy or not. It might have been too faint. Like NGC 5674 it isn't on either Herschel 400 list.

Further to the southeast is the very low surface brightness galaxy UGC 9385. At only 85 million light-years it is much closer but also much fainter. It is about 60,000 light-years across its two very widely spread diffuse arms. Even combining its image using data from both nights 4 years apart, it is too faint to get a good measurement on it. While NED classifies it as an irregular galaxy it seems to have a barred spiral structure to my eye. The arms seem spread unequally with the northern one further from the core than the southern and less well defined as well.

The image contains several candidate quasars (CQ) in the annotated image. NED also listed several dozen ELG's (Emission Line Galaxies). While most show in my image they are very faint. They are likely very active galaxies with super bright cores to be seen at the distances they are. I have to wonder if some are almost quasar bright. I've only marked two on the image one with a look back distance of 7.21 billion light-years and another even further at 8.50 billion light-years and a z of 1.19. All are starlike showing no hint of "fuzz" in my image. The latter having a magnitude of 22.7 per NED so these are very faint objects. I wish I knew more about what they might be.

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

Related Designations for NGC5674

NGC5676

NGC 5676 is a two-armed barred? spiral whose arms knotty and ill-defined after a point that it is almost a flocculent galaxy. NED classifies it as SA(rs)bc with HII emission. NGC project says Sc while Seligman says Sbc. Several papers say it has a short low contrast bar which I thought I saw. Or did I? Several HII regions came out in my rather low-resolution image thanks to below average seeing. The brightest is just right of what NED lists as a separate galaxy and is listed as such in several catalogs but which to me is just one of many knots in the galaxy's arms. I've pointed to it because it almost points to the largest HII region seen in my image in the galaxy. Redshift puts it 100 million light-years distant while non-redshift measurements say it is a bit further at 110 million. Very good agreement. Assuming the round 100 million light-year distance I measure its diameter at at least 120,000 light-years. A rather large spiral maybe on par with M31.

The galaxy was discovered by William Herschel on May 15, 1787. It is in the original Herschel 400 observing program. My notes from that on May 17, 1985 at 120x using my 10" f/5 under fair conditions due to high humidity and thus low transparency reads: "Small oval galaxy. The starlike nucleus is seen with averted vision. Seems 3'x2' rather than the 3'x1' as described. Grows larger and rounder with averted vision." My image measures the galaxy as 4.0'x 1.92'.

The annotated image points to everything NED had a redshift value for. Those with only coordinates for a catalog name are just listed as G for Galaxy UvES for Ultraviolet Excess Source (usually a candidate quasar) or GC for a galaxy cluster. Only one cluster also had a redshift distance for its bright cluster galaxy. In that case, both were photographic redshifts and disagreed. So both are listed with the cluster's value first. Another object is a candidate BLAGN (Broad Line Active Galactic Nucleus). These usually are quasars but in this case, the host galaxy is clearly evident by its orange color. Broad lines mean high speed that blurs the lines so they are likely coming from near the massive black hole at its core.

Several galaxies I'd have liked some info on had little in NED. One is the very faint low surface brightness fuzz patch southeast of NGC 5676. I suspect it is a very faint nearby dwarf but with no information who knows? Further east and south of MCG +08-27-001 is what looks to be either an irregular blue galaxy or a disrupted galaxy.

This night fits my weather lately when I can get either good seeing or good transparency but not both. This had good transparency but that meant below average seeing. So it did go deep but fine details in the galaxy, like a lot of HII regions, were lost to the poor seeing. Seeing was a bit below 3" rather than my average (before this stint of lousy conditions) of 2.25" to 2.5".

14" LX200R @ f/10, L=8x10' RGB=2x10', STL-11000XM, Paramount ME

Related Designations for NGC5676

NGC5689

This field of 5 NGC galaxies is located in northern Bootes. 4 are part of the NGC 5689 group at about 110 million light years. The fifth is about half the distance. The four at about the same distance are; NGC 5682 discovered by George Stoney on April 13, 1850, NGC 5689 for which the group is sometimes named was discovered by William Herschel on May 12, 1787, NGC 5693 also discovered by George Stoney on April 13, 1850 and NGC 5700 discovered by Lawrence Parsons. While his employees discovered many of the galaxies some attribute to him this one he likely really did discover. The 5th member NGC 5683 that's much closer was also found by George Stoney on April 13, 1850. George Stoney was one of Lawrence Parsons' astronomers.

NGC 5689 is in the original H400 program. My notes from that read: May 17, 1985, night fair but humidity limiting brightness some, using my 10" f/5 at up to 120x; Small, thin galaxy with fainter outer halo. At first glance, it seems nearly round then with averted vision you see the faint outer raches that define it as an edge on galaxy. Averted vision a must for this one to see its true nature." Humidity may have had a lot to do with the need for averted vision that night. At the time I didn't appreciate how much it can dim an object.

NGC 5689 is about 130,000 light-years across so a bit larger than our galaxy but much redder indicating star formation is very low in this galaxy. It also seems to have a much larger core and thus its supermassive black hole may be quite a bit larger than ours. Since the galaxy still contains quite a bit of dust and gas could a large black hole be the cause of the lack of new star formation? I've seen this said about other galaxies but this wasn't one of those.

Of the four found at Birr Castle (still occupied today by a direct descendant of Lawrence Parsons, less the 72" telescope) NGC 5682 is about 53,000 light-years in size. While note mentioned I see two plumes, one from each end. The southeastern one going southwest and larger than the faint one to the northeast. It appears it interacted and maybe ate something in the not too distant past. I found nothing in the literature about this, however. NGC 5683, the smallest in angular size but nearest so easily the smallest of the 5 is about 8,000 light-years across. It seems rather well-formed for such a small galaxy. Is it loaded with dark matter? NGC 5693 is about 53,000 with a long pulled out arm that could have fit into Arp's category for galaxies with one heavy arm. That is the only easily visible arm of the galaxy. Is it the one that created the plumes of NGC 5682? Again I found nothing on this possibility. Lastly is small NGC 5700. I get a size of 33,000 light-years for it. Yet another member of the group is the very faint PGC 052263. I get a size of about 40,000 light-years but it is of such low surface brightness it may be somewhat larger.

Of late, most objects I'd consider quasars, NED has listed a candidate quasars (CQ in my annotated images) but this field has only full-blown quasars, none are listed as being a candidate. One is even listed under an old designation for them, Blue Stellar Object beside as a quasar. That one really is strongly blue in my image. No asteroids and otherwise the field is rather normal.

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

Related Designations for NGC5689