IC4215

This field is in eastern Coma Berenices. Why I put it on the to-do list is lost. It's been on the list now over 10 years at a low priority. I finally got tired and those on the list for 10 or more years got their priorities bumped up so are sometimes taken now. But back then I was lax as to why I put something on the list. This one is a total mystery. Was it IC 4215 at 910 million light-years. It has a faint dust are in the core region that doesn't extend very far from the core. Though I seem to have picked up more of it than Sloan did. It is a rather red and dead spiral. It was discovered by Stephane Javelle on June 15, 1895. I measure it at just a bit under 100,000 light-years in size though Seligman siting a somewhat smaller angular size and putting it 10 million light-years closer says 85,000 light-years.

Or was it the two blue smudges of a galaxy? PGC 046189 and the very odd rectangular one at the top. NED considers the PGC galaxy part of the [TSK2008] 0803 galaxy group which it says as 4 members at 56 million light-years. Since the rectangle galaxy is also at about this distance I presume it is part of the group. It has an identity issue. The yellow blob at the south end is listed as a separate galaxy but its size is rectangular and extends about a third of the way up the blue rectangle. NED also lists the northern 2/3rds of the rectangle as another galaxy using the coordinates of a blue star cloud near the upper end but ignoring other clouds further north. So is it two galaxies? I can't see any indication it is in either my image nor the Sloan image. NED places the bottom part at only 14 million light-years while it puts the upper part at 57 million light-years. Assuming the entire blue rectangle is at 57 million light-years the galaxy is only about 15,700 light-years long and 3,500 light-years wide if we are seeing its full width. Or is it being seen edge on? Was this quandary why I put it on the list?

PGC 046159 is about 26,500 light-years long assuming it is 55 million light-years distant. There is one single non-redshift measurement that puts it at 70 million light-years but I've found single such measurements unreliable. I much prefer when there are dozens and then I use an average or median distance as those usually are more accurate averaging out errors and uncertainties.

The field contains several candidate quasars. I think it likely most if not all are actually quasars but NED still needs more info to make that determination solid. I didn't include those I thought might fail to be quasars. NED lists those that do fail to make the cut as "Failed Quasars". None were on the list for this field.

There are no asteroids down to magnitude 21. I didn't realize this image went well below magnitude 23 or I'd have searched deeper but nothing caught my eye in the original FITS luminance stack.

There are quite a few quasar candidates at 10 to 12 billion light-years. If right that is somewhat unusual as the very early universe doesn't seem to contain all that many quasars and to have this many in one small field I find surprising. Maybe it indicates the distances aren't right and these aren't quasars. I'm sticking with most being real quasars.

For not having any idea why I imaged this field, I found it interesting after all. Now did I cover what drew me to it in the first place?

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

Related Designations for IC4215

IC4304

This field in southeastern Canes Venatici contains a large group of galaxies at a distance of about 350 million light-years. 6 of them are bright enough to have made the IC catalog. They are all quite red with the sixth IC imposter that redshift puts nearly 70 percent more distant. I'd have expected this group to have a designation but I couldn't find one. Three of them (ICs 4304, 4305 and 4306) form the WBL 457 group. Others, mostly fainter than the IC galaxies are lumped into other three and four galaxy groups but nothing I find encompasses the entire group. I find that odd. In any case, the IC galaxies are (starting in the center and working out), IC 4304, 4305, 4306, 4302, 4301 with IC 4300 being the outcast. There's another bright member of the group, UGC 08609 in the northeast corner that's a nice face on blue spiral finally adding a color other than red to the image. It appears there's been no work done on this group so I can't report further. Odd how such a nice group has been ignored like this. How far outside my frame the group continues I didn't look up.

All but one galaxy in the field are either members of this group at about 350 million light-years or more distant but for one exception. That is LEDA 214123, a blue S01 galaxy at 220 million light-years though it is smaller than most of the true members. Still being blue it adds some much needed color contrast.

One of the smallest members of the group is ASK 533588.0 on the western side of the frame. It has two companions that appear to be in its halo. They are likely far more distant galaxies in the same line of sight but without redshift data on them I can't say for certain they aren't colliding with the known member or with each other.

There are several distant galaxy clusters in the image. Some had an anchoring bright cluster galaxy others had none. If there was such a bright cluster galaxy it is noted in the annotated image. Often these have a spectroscopic redshift that's more accurate than the photographic one use for the cluster but in this case, all were photographic and identical to that of the cluster so aren't listed twice.

The IC galaxies were all discovered by Stephane Javelle. IC 4300 was not seen until June 16, 1903. The others were all seen on July 1, 1896.

As usual with my annotated images distances are in billions of light years and spectroscopically determined unless noted differently (p for photographic, Est for estimated etc.) Distances found by non-spectral means, often Tully Fisher, are the median of as many as NED has listed and are shown in parentheses.

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

Related Designations for IC4304

IC4630

IC 4630 was suggested to me by Sakib Rasool. It is a spiral starburst galaxy which is likely the result of a merger in progress -- SIMBAD considers it two galaxies while NED sees only one as I do. Though the plumes indicate it is the result of a merger. A merger some feel is still going on. It is a mostly white galaxy with two plumes. NED classes it as S? It is located in Hercules below the keystone at a distance of a bit under a half billion light-years. Besides the plumes, it has a nearly complete arc around a bright core. I find little on it other than it is included in many papers about mergers in progress. The annotated image shows a number of related galaxies at its redshift. Most are smaller galaxies. I've annotated them by catalog entry rather than the generic G or Q used for the rest. With so many in the immediate area, it's not much of a stretch to think this galaxy has been feeding on its dwarf neighbors for a long time. IC 4630 was discovered by Stephane Javelle on July 27, 1903.

I got a surprise when I looked at the first image as it came in as there was a bad reflection in the upper left corner. I moved the scope slightly but it was still there. Reflections move or vanish when the scope's aim is changed slightly. I let it go expecting to remove it during processing. That was last June. Before I took it out when processing the image I checked the Sloan image of the area and there was the "reflection" just as it appeared in my image. Like IC 4630 it was quite white in color on the Sloan image. So it is real. Real what I don't know. Neither NED nor SIMBAD shows anything in that position. It likely is a small piece of rather bright IFN. I see some hints of other pieces throughout the frame, just much fainter.

As happens rather often there was what appeared as a trio of interacting galaxies due east (left) of IC 4630 about two-thirds of the way to the edge. Neither NED nor SIMBAD shows anything at their location. The Sloan Survey image shows it is real and very blue. Could be either a single rather disrupted looking irregular galaxy or two or three superimposed blue galaxies. Two other faint fuzzies I was interested in are also missing from both NED and SIMBAD. All are noted with a question mark in the annotated image.

Also in the upper left corner and well within the mystery "reflection" is this entry "GC/C 4 or 6 Members 4.14p/3.58". NED shows two galaxy clusters at almost the exact same position with an error circle sufficient to include both. One has a photographic distance based on photometric data, the other uses spectroscopic data. Are they the same cluster or two different ones? Another much larger one at 3.67 billion light-years is in the area. Does it include the other two? NED lists no size for any other than galaxy count. It appears I'm not picking up but a very few of the cluster member other than the anchoring bright cluster galaxies.

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

Related Designations for IC4630

IC4954

IC 4954 and IC 4955 are really small parts of one huge object. For the particular viewers out there IC 4954 consists of the two nebulas at the top with IC 4955 being the bottom one. Some sources consider the middle object to be either part of both or not part of either. But since they are all part of one star forming region that issue is rather moot. This star forming region has formed a huge star cluster. It is many times the size of my field of view. Some of the stars are illuminating dust and gas left over from their formation some 6 million years ago, thus illuminating these two nebulae. The entire cluster is known as Roslund 4 and is located some 6 to 8 thousand light years away. The exact distance is still rather uncertain.

The middle portion shows a sharp edge on the right side where several bright stars are seen. This edge is a shock front caused by the super bright light and strong solar winds of these stars hitting the remaining dust and forming them into a shock front of expanding dust and gas. Where these stars have blown away the dust and gas you see a huge swarm of background stars. These are stars of the Milky Way galaxy that lie far beyond this star forming region. Most of these are still hidden by the dust and gas allowing only foreground stars to be seen. The brilliant blue stars scattered about the image as well as some of the dimmer stars are members of the Roslund 4 cluster. It is located in the faint constellation Vulpecula (the fox). For those of you with hip waders, you can read more about it at:
http://www.iop.org/EJ/article/1538-3881/128/1/330/204077.text.html

The nebulae were discovered by Edward Barnard. Unfortunately, the date is unknown.

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Related Designations for IC4954

IC4996

IC 4996 is a small tight open cluster in Cygnus about 5600 light years away. WEBDA puts its age at only 9 million years. So young, a couple of its stars haven't yet reached the main sequence so it is studied to learn more about rather rare pre-main sequence (PMS) stars. I didn't take time to look into those papers. The cluster was discovered by William Herschel on September 20, 1786. It isn't in either of the Herschel 400 observing programs.

I left no notes as to why I put this one on my to-do list. It may have been a mistake as I only took 2 frames of each color and one very poor luminance frame I didn't use. This is a pure RGB image with only those 6 RGB frames.

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Related Designations for IC4996

IC5146

IC 5146 is commonly known as the Cocoon Nebula. It is located about 4000 light-years away and is seen against the Milky Way in Cygnus the swan. Nebulas can be either reflection nebula in which they shine because starlight is illuminating them same as the sun illuminates the Earth or because strong ultraviolet light excites the gasses it is made of to glow much like electricity causes a neon light to glow. There's a third possibility, the gasses and dust block and/or absorb light making a dark nebula. All three are going on here.

First off the gas and dust in this area is condensing into what will become a major open star cluster given enough time. Right now most of the stars are hidden behind the dust and gas creating them and can be seen mostly in infrared light which can penetrate the dust. But in the center, a very massive cluster star formed near the edge and blew a hole allowing us to look in a bit. This is the bright star in its center. I say bright but at magnitude 9.7 it is nearly 100 times fainter than a 5th magnitude star seen by the unaided eye. It is very massive however and is classed as a B1V star. It is known as BD+46 3474. B1V stars emit a lot of light, more in ultraviolet than visual light but still, the visual light is tremendous. The result is the UV light causes the hydrogen gas on the edges of the cloud to glow due to hydrogen-alpha emission. It also is illuminating the surface of the cloud but this light is mostly lost to the much stronger hydrogen-alpha emission. But at the edges, the UV light is too weak to ionize the hydrogen. There we see the blue of the reflection nebula where it doesn't have to compete with the hydrogen-alpha emission. Notice around the illuminating center star other stars are seen. These are likely seen through the hole the B1V star has created letting us see a very few of the more normal cluster stars.

Harder to see, due to my limited field of view, is that this nebula is actually much larger than the reflection and emission nebula. There not enough light exists so it is dark and seen only because of the background stars it hides. It is known as Barnard 168. It extends several degrees, mostly to the upper right of my image. Wide field images show it almost like a dark comet tail coming from this bright nebula.

Also, the dark bands are seen in the bright nebula, but for the center hole, are due to the hydrogen gas absorbing the UV light that would otherwise cause the nebula to glow. This is because the gas is too dense to glow with hydrogen-alpha emission. There's a lot going on in this object.

Unfortunately, I took this right after I started doing color imaging and before I knew what I was doing. I need to dig out the original FITS files and reprocess it with today's tools. Back in 2007 when this was taken I ended up processing it two ways, one too gentle and one too harsh. Also, I didn't know how to preserve star colors so most are too saturated to show color except around the edges. It is in need of correct processing but this old image will do for now. I've included 2 versions, neither what I would do if I had the original data handy to work with. It was discovered by Max Wolf on July 28, 1894.

Many images you see of this one use narrowband filters to isolate the hydrogen, oxygen and sulfur that cause this nebula to glow. Then RGB data is added to pick up the reflection parts. Only having a hydrogen filer this is a pure LRGB wideband image. The hydrogen emission seemed plenty strong without resorting to narrowband filters as those located under light polluted skies have to do. but I used 3 times more luminance data than I usually do. Not so much because it was needed but because I didn't know it wasn't really necessary. I did use my normal amount of color data however which is rather strange. Shows my state of ignorance all those years ago.

14" LX200R @ f/10, L=12x10' RGVB=2x10', STL-11000XM, Paramount ME

Related Designations for IC5146

IC5337

IC5337-IC5338-ABELL2626IC 5337 and 5338 form the core of the Abell 2626 galaxy cluster. The cluster is located almost dead center in the Great Square of Pegasus and is about 720 million light-years distant. The cluster is listed as richness class 0 meaning it has 30 to 49 members. Its diameter is listed as 79 arc minutes, so covers an area 8 times that of my frame yet I show well over 50 galaxies that appear to be members of the cluster that have distance estimates. Many more have no distance estimates but likely are also cluster members. That leaves me wondering how this count is arrived at.

The cluster's morphology class is I-II meaning it has an elliptical galaxy at its core but also at least one other major galaxy and other elliptical galaxies. IC 5338 is the cD-BrClG for the cluster while IC 5337 is the second major galaxy. Usually, these are also ellipticals but a large spiral will do.

IC 5338 is a strong radio source known as 3C 464. Also, several sources say it is "... two close galaxies separated by 3.4 arcsec embedded in an asymmetric halo extending to the SW component. Galaxy b (SW) has line emission and is associated with the radio source 3C 464." I agree the halo is asymmetric but to me, the other "galaxy" is just a field star superimposed in the galaxy. NED gives no galaxy or star at its position. At least I was going to say it was a field star until I looked at an HST image. It does indeed appear to be a galaxy in the HST image. I measure the size of the pair at about 350,000 light-years, probably larger than that as the edge is very hard to determine likely getting larger the longer the exposure time.

IC 5337 is an edge on spiral. NED classifies it as a spiral while Seligman says Sc? It too is huge, at least for a spiral, with a size of about 220,000 million light-years. That makes it twice the diameter of our galaxy. Their size becomes even more obvious when compared to all the other galaxies in the cluster. Many like the red S0-like galaxy to the upper right of IC 5337, are actually about the same size or larger than our own galaxy yet seem small compared to these two. They were discovered by Stephane Javelle sometime in 1897. I can't find an exact date. I would assume he saw them on the same night.

As usual of late seeing was below normal so details I'd normally pick up were lost. I was surprised the not one quasar is listed in the field. There is, however, one asteroid toward the right center of the image. See the annotated image for details.

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

Related Designations for IC5337

IC568

IC 0568 is a huge barred spiral in western Leo about 2.5 degrees above the ecliptic. That usually means lots of asteroids but the night was so hazy only one was bright enough to be visible even in the original FITs luminance stack. Its trail is very short, only a few seconds long. It was at the end of its retrograde loop and starting to move back to the east. The motion was about equally to the north and east

I say huge as I measure it at 244,000 light-years across. If it is tilted, even a little bit, that will be too small. The other IC galaxy at a similar redshift is about 79,000. Has something drawn out the arms of IC 0568 to this unusual size? NED lists what appears to me to be just a bright area in the upper arm. I've labeled it in the annotated image. It has a similar redshift. That could mean it is just part of the galaxy or that it is now merging with the galaxy. I favor it being part of the galaxy. I needed a much better night to have pulled the extended arms out better than I did. I had nothing below magnitude 22 that was visible. So the annotated image is mostly barren of faint distant galaxies. Many nearby ones had no redshift data.

IC 0570 has a rather off-center core with faint arms to the west but not the eastern side. There's a flat edge on galaxy on the northwestern edge of the galaxy. I found it not in any catalog carried by NED or SIMBAD. How it was missed I don't know.

Both IC galaxies were discovered by Stephane Javelle on January 15, 1894.

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Related Designations for IC568

IIHz4

II Hz 4 is a pair of empty ring galaxies. The only pair I'm aware of, at least in the part of the sky I can cover. If anyone knows of another please let me know. The second empty ring apparently is due to II Hz 4:[RMV2008] R2. They are located in southern Lynx about 590 million light-years away. The core of II Hz 4 is well off center. The second ring appears part of the companion I Hz 4:[RMV2008] R2 to the north. It has a rather normal looking disk shape with core and eastern side. Western side can't be seen. It has apparently been drawn into the faint ring that loops up and around. A nasty "bright" star makes seeing all this difficult as it casts a glare over the faint ring. Redshifts of both are virtually the same making it quite likely these are an interacting pair.

As you will see in the annotated image, these two are pretty much alone in their spot of the universe. I found no other galaxies within a couple hundred million light-years of them in my frame. Odd how two such galaxies managed to collide so violently with all that space to roam around in. None of the papers on these two addressed this issue.

There are several galaxy clusters in the image. Each is anchored by a Bright Cluster Galaxy (BrClG). I've noted the position of the anchor galaxy and its distance. They contain from 10 to 12 galaxies in an unknown radius. Oddly the cluster distance is slightly different than that of the anchoring galaxy. The difference was small so rather than clutter the annotated image I just used that of the anchor galaxy.

These appear to be part of a much larger cluster ZwCl 0856.6+3710. It is said to have a diameter of 19 minutes (almost the height of my image which is 22.5 minutes) so it covers a major part of the left side of the frame. It is listed as having 104 members but no distance or even distance class. Likely this is because it is just indicating this is a rich part of the sky for distant galaxies rather than they are all gravitationally bound to one center of mass. I've indicated the center position even though there's nothing at that location either in NED or my image.

The image contains several quasars out beyond 10 billion light years. When quasars were first discovered they were almost all blue. Thus they were called blue quasi-stellar objects. The hunt was on looking for very blue stars in hopes one was another blue quasi-stellar object. After a while, it was seen many were not blue and the search needed to be extended. Then they were just quasi-stellar objects which was shortened to QSO or quasar. Quasar also became a TV brand of Motorola solid state TVs during the switch from tube sets (but for the picture tube). It was later sold to Matsushita (now Panasonic) and renamed Quasar Electronics Incorporated. But I digress. In my images, some quasars are blue while others are white or even reddish. This is the first one I can recall that all are blue, even the very distant ones. Just a statistical fluke I find fascinating.

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Related Designations for IIHz4

IIZw073

II Zw 073 is a very strange pair of galaxies in northeastern Bootes about a quarter billion light-years from us. Individually they are UGC 9796 and MCG +07-31-049. At that distance, you might not think there is much to see but the western galaxy UGC 9796 is a polar ring galaxy with a huge polar ring. While the galaxy itself is rather small with a diameter of its spiral disk being 28,000 light-years across the polar ring is about 115,000 light-years across. Its polar ring is 4 times the size of the galaxy. A very strange situation indeed. The UGC's original entry in 1973 reads: "Diffuse 'spindle' (dwarf?) with elongated 'core', probably superimposed companion". This was before polar ring galaxies were really known so the confusion isn't surprising. More surprising to me is that it is an entry in the Flat Galaxy Catalog! It is listed in the addenda catalog as FGC 224A (the "A" identifies it as an entry in the addenda catalog Apparently they are considering the polar ring the plane of the galaxy. Even then the length is only about 4 times the width, not 7 times needed to make the FGC.

Its eastern companion, MCG +07-31-049 is listed as a starburst galaxy by NED but lists no other classification for it. It too is a quarter billion light-years away. There are several other galaxies in the image at this distance. One is another flat galaxy, this one looks like it may deserve the designation. It is FGC 225A, also from the addenda catalog. CGCG 221-045 is a LINER galaxy. It has a companion, ASK 403585.0. This pair is again a quarter of a billion light-years distant. In the lower left corner is KISSR 1929. It appears to be a "Sloshed" galaxy". These are galaxies with the core well off center. Usually, this is considered evidence of interaction with a much more massive galaxy. However, there isn't a nearby candidate that I found, even well out of my field. Starburst, polar ring and LINER galaxies can all be indications of prior interaction. With it being virtually certain in the case of a polar ring galaxy. This group may have been a much tighter group in the past allowing these interactions that we see today.

There are several quasars in the image, one closer than some of the distant galaxies which is rather surprising. Two are labeled as BAL quasars. This means they have broad absorption lines in their spectrum. If you are curious about what this means it is explained rather well in not too technical of terms at: http://arxiv.org/ftp/astro-ph/papers/0610/0610656.pdf in the introduction part of the paper. Those wanting more can read further.

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Related Designations for IIZw073