NGC7242

NGC 7242 is a very large galaxy that anchors the NGC 7242 group. It is about 250 million light-years distant. I can trace the plumes off each end of the galaxy out about 490 seconds of arc on the luminance FITS. That would translate to almost 600,000 light-years for its diameter. If true that's one huge galaxy. I suppose it is possible some of this is IFN or something else. Measuring the obvious diameter I get 334 seconds of arc. That is over 400 million light-years. No matter how you look at it, it is one big honker of a galaxy to use the scientific term. NED classes it as E+? and cD?. The NGC project says simply E. This would indicate they are unsure how much of its elongation is due to its nature and how much has been caused by tidal plumes created when it interacted and likely ate many members of the group. That is, much of its shape may be due to indigestion from overeating in the recent past. It was discovered by August Voigt in 1865, possibly in August.

IC 5195 is seen against the galaxy to the northeast. Its redshift puts it a tad closer which is likely the case. While NGC 7242 is rather dust free and thus somewhat transparent I doubt it is as transparent as it would have to be to see this small galaxy through it. I found no classification for this small, but rather bright, galaxy.

IC 5193 another spherical galaxy to the southeast that is considerably larger than IC 5195 but it too shows no classification at NED. IC 5193 was found by Edward Barnard on December 5, 1888. IC 5195 was found by Guillaume Bigourdan on October 16, 1895.

NGC 7240 to the southwest shows some hint of a tilted disk though its overall shape is nearly round. It is classed as S0-:. It was discovered by Édouard Stephan on September 26, 1873.

I need to do some explaining here based on questions I've been getting. The S0 class was once considered it's own with no subdivision. It sits between elliptical and spiral showing characteristics of both. But as these were studied it was decided some were more elliptical than spiral and some were more spiral than elliptical. Thus two other classes were created S0- and S0+ respectively. The colon means there's some question if this is right or not. So this one is an "early" S0 though there's still some debate. Early comes from the now discounted idea that galaxies started as round ellipticals, which elongated turning into S0 galaxies which then developed arms which gradually got more widely spread out. While we now think this very wrong and to some extent backward the idea that a moving toward the elliptical from the spiral means a younger (early) galaxy and moving toward the spiral direction means older (late) is still used in terminology. The minus or plus sign is usually a superscript but that's a character that depends on what font set your computer uses and with this going to all parts of the world I left that out. Sometimes I've used the ^ to denote superscript and a second one to denote the end of superscript. NED usually does this. Sometimes if the S0 is quite balanced then they use the superscript 0. Since doing that is also may not work with all fonts and to prevent the confusing S00 it is usually written S0^0 and if there's a question about this then you'll see S0^0^: or sometimes S0^0^? Another system, not used by NED, would make these three S0(1) S0(2) and S0(3). Seems easier but NED doesn't use it. Now that I've got you all confused I'll move on.

To the upper right of NGC 7240 is IC 1441 classed as SBa? A tightly wound barred spiral, they think. It was discovered by Guillaume Bigourdan on September 25, 1889. IC 5192 is to the southeast making a nice triangle with the other two. NED has little to say about it, however. To its west is IC 5191 which has the NED class of S0-a. They were discovered by Edward Barnard on December 5, 1888. So as soon as you think you understand this they throw another curve. This is even later than S0+ but still not quite Sa. It can be written S0/a as well. The MCG catalog gives its coordinates as the same as IC 1441 in error. So if you wonder why I need two days to do these, its things like this that can really take up time figuring out who is right and who is wrong.

I've listed a few other galaxies in the annotated image, some with redshift data, some without if they seemed likely to be members of the group. Most of the rest are anonymous in NED but for a few small IR galaxies in the 2MASS survey.

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

Related Designations for NGC7242

NGC7243

NGC 7243 is an elongated cluster of rather bright blue stars in Lacerta. It was discovered by William Herschel on September 26, 1788. It is in the original H400 program. My notes from June 14, 1985 on a fair but humid night with my 10" f/5 at 60x reads: "Large scattered cluster in two parts as it seems cut by a dark lane. This seemed to fade away when the cluster was partly obscured by a thin cloud. Visually, to me, it is more a star cloud than a true cluster." I think I see the dark lane I referred to.

There's only one galaxy in the image with redshift data. It is in the lower right corner and is LEDA 167750 at a redshift distance of about 580 million light-years. The much closer star cluster is about 2600 light-years distant per WEBDA. They give its age at 114 million years. While reddened slightly at 0.22 magnitude its very young age makes most of its brighter stars coming out very blue even with the smoke this was imaged through.

I needed something big and bright to make processing easier for a change, this is it. Not very interesting but is an original H400 object, one of the few I've left to capture that are far enough north for my latitude and observatory wall.

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

Rick


http://www.mantrapskies.com/image-archive/NGC/NGC7243/NGC7243L4X10RGB2X10-67.JPG
http://www.mantrapskies.com/image-archive/NGC/NGC7243/NGC7243L4X10RGB2X10-67CROP.JPG
http://www.mantrapskies.com/image-archive/NGC/NGC7243/NGC7243L4X10RGB2X10.JPG

Related Designations for NGC7243

NGC7245

NGC 7245 is a Trumpler class II1p (one source says II2m) open cluster in Northern Lacerta. Its classification indicates it is a cluster detached from the background with little concentration made up of stars with evenly bright stars and less than 50 stars. From my image, it seems very hard to distinguish from the background. It's the blue stars a bit up and to the right of center. I don't understand why I did that. Probably a coordinate error on my part when I wrote the script file to take the image. The cluster was discovered by William Herschel on October 14, 1787 and is in the second Herschel 400 object list. This is what put it on my to-do list at a rather low urgency rating. These get taken when waiting for something better to get into position.

NGC 7245 is a rather blue cluster because its stars are young. WEBDA puts its age at about 175 million years. Reddening from our galaxy's dust is about 0.47 magnitude though it is still quite blue thanks to the young age of its stars. Its distance is about 7,000 light-years. I measure it at about 5 minutes in size though this is very approximate. That would make it only 10 light-years across.

What I didn't know at the time was the existence of a second open cluster in the frame. It is found up and to the left of NGC 7245 and is easier to distinguish in my image due to all the faint stars. This cluster is King 9. WEBDA puts its age at over 3 billion years or 18 times that of NGC 7245. That explains why it has no blue stars. They've long since died. Its distance is listed at 26,000 light-years making it nearly 4 times further away. I measure its long axis at about 1.5' which makes it about 11 light-years across. But other sources put its size at 3 minutes making it 22 light-years across. About the same as NGC 7245. Even though it is much more distant and seen along nearly the same line of site WEBDA puts its reddening at only 0.37 magnitudes, a bit less than NGC 7245 which I find rather odd. It is Trumpler class I1m so is detached from the background and highly concentrated with stars of more even brightness and between 50 and 100 stars making it a richer cluster as well. Sometimes when imaging a dud something better shows up.

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

Related Designations for NGC7245

NGC7246

NGC 7246 also known as IC 5198 is a spiral galaxy in Aquarius about 170 million light-years distant (130 million by a single Tully-Fisher measurement. I suspect the redshift distance is closer to the right value as you usually need several Tully-Fisher measurements to home in on a distance using that method. It was discovered by William Herschel on September 6, 1793. It isn't in either of the H400 programs.

There's nothing much interesting about this galaxy. But it wasn't my real target. I was more interested in the two highly distorted galaxies on either side of it. Since NGC 7246 appears pretty normal I wondered if these other two were related? If so could their distortion be due to a near collision between them? Unfortunately neither NED nor SIMBAD had anything on these. NED didn't even have the LEDA galaxy in its various databases that I could find. The APMUKS galaxy wasn't in SIMBAD that I could find. I came up empty trying to answer these questions.

This field is below my normal -15 degree declination cutoff and is very noisy being hurt by both seeing so low in the sky and by fog coming off the lake that cost a good magnitude or more and cast a bright haze over the entire image. As the fog was constantly changing it created lots of gradients over the image. Removing them likely removed the fainter parts of both galaxies. So this is another for the reshoot list but unless I can find something on these two distorted galaxies, I doubt that will happen.

I'd wanted more time for this one but the 11 frames I did get was all I could before it went into my Meridian tree. Since then the weather hasn't allowed another try and it is now lost to that tree for this year. So I went with what I had. With only 1 extra frame I decided to make it a blue filter image as blue is severely hurt by the fog rising over the lake. I can't see it helped to any significant extent.

14" LX200R @ f/10, L=4x10' RG=2x10' B=3x10', STL-11000XM, Paramount ME

Related Designations for NGC7246

NGC7250

NGC 7250 is considered to be a merging pair of galaxies. Seems worthy of Arp's list but wasn't included. It is in the constellation of Lacerta about 40 to 45 million light-years distant. It is somewhat obscured by our galaxy's dust. Even with 12 subs, the faint outer regions were just that, faint. It must be a lovely sight without the dust. It is classed as S-irr by the NGC project and Sdm? at NED. It is a starburst galaxy which isn't surprising for a recent galaxy merger. Still, it appears rather small in angular size. So small I imaged it at 0.5" per pixel and it still isn't very big. One note indicates the brightest star-like object to the northwest (upper right) of the core about 24 seconds of arc from the center is a "companion". Do they mean the remains of the merging galaxy? For such an interesting galaxy I found very little on it. Probably because it is nearly impossible to separate the signature of features of its spectrum, radio and visual, from those of the Milky Way itself. This is often the case with galaxies seen this close to the galactic plane. I suppose the galaxy would be much bluer if not for the galactic extinction as well. It was discovered by William Herschel on November 8, 1790. It isn't in either H400 program.

Few other galaxies are in my image, none with redshift data. The brightest is 2MASX J22182750+4035226 to the east-northeast of NGC 7250. NED lists only one other galaxy in the entire field, though I see a couple dozen. The one it lists is in the upper right corner of the image. It is rather red in color and northeast of the first bright star down from that corner. Several others are in the area, it is the brightest. It is 2MASX J22173483+4038271 if you just had to know.

14" LX200R @ f/10, L=12x10'x1 RGB=2x10', STL-11000XM, Paramount ME

Related Designations for NGC7250

NGC7260

NGC 7257/7260 is located in northern Aquarius about 200 million light-years distant by redshift measurements. Due to a positional error mid 19th century, it has two numbers. There is no object at the position for NGC 7257 which all now consider a duplicate observation of nearby NGC 7260. It was discovered by Albert Marth on October 1, 1864.

I put this one on my list due to its rather lonely northern arm. There are only two other galaxies in the field with redshift data. Most of the others are from automatic plate surveys. There is an apparent double galaxy to the southwest of NGC 7260. The lower one, 6dF J2222166-041500, has a redshift that puts it at 208 million light-years so it is a member of the same group as NGC 7260. Its companion isn't even listed in NED though there is a plate survey entry for the pair. None of this is any help to determine if it is a true companion or just line of sight. There does appear there's some distortion to both so I'll say they are an interacting pair for now.

The only other galaxy with redshift data is at the far middle right of my image. It is listed as nearly 340 million light-years distant so not likely related to the other two. It is a strong IR emitting galaxy from the 2MASS catalog, 2MASX J22213394-0406426.

There are three asteroids in the image. Each has a very different direction vector. The brightest, 2000 QH176, is moving prograde, that is to the east which is not all that common in my images. The other two are barely moving. I'd not have made an annotated image but for them. They are so nearly star-like and difficult to find I decided an annotated image would be needed to point them out. 2003 SJ32, below NGC 7260 is moving retrograde but so slowly moving west most of its motion is to the north due to it moving up in relation to the plane of the solar system. This likely means it is turning from retrograde to prograde motion. The third one, further east but at about the same declination as the other two is (62308) 2000 SH118 and it to is moving west but mostly south rather than north. So it too is likely at the turn around point. Retrograde motion happens when we pass the slower moving asteroid. While it is moving in the same direction as we are, as we pass it, it will appear to move backward same as the car we pass on a highway appears to move backwards in relation to the very distant background. This false westward motion is called retrograde motion. Once we get so far ahead we are seeing the asteroid on the opposite side of the sun then its forward motion is quite obvious since relative to the background stars we are moving in the opposite direction. Midway between these two points, we see it almost stop in the sky. It would stop if it was in the exact same plane as the earth. Since it won't be, when stopped east to west it will still be moving up or down in relation to our orbital plane and thus move mostly vertically as these two are doing.

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

Related Designations for NGC7260

NGC7261

NGC 7261 is an open cluster in southern Cepheus located about 5500 light-years away according to WEBDA. They place its age at only 47 million years making it a rather young open cluster. So why are the stars only sort of blue? A cluster that young should be full of very blue stars. The reason is it is reddened by nearly a full magnitude by dust in our galaxy that lies between us and the cluster. The cluster is ill-defined, especially at my image scale. I reduced the scale to 1.5" per pixel and it is still rather hard to define. The pros seem to have a problem as well as I found 5', 6', 8' and 10 to 15 minutes for its size. NGC project classifies it as Trumpler class II3m while Seligman says III1p. It was discovered by John Herschel on October 5, 1829.

Professor Harold Corwin says of it: "JH's cluster is probably the scattered group of pretty bright stars, stretching nearly north-south across an area 15' by 10', about 20 seconds preceding his position for the bright star on its following edge. There is a smaller core (7' by 5') of generally fainter stars about five arcminutes north-northeast of the center of the larger group. Is this perhaps a background cluster?"

While the cluster is hard to make out at my image scale it does stand out in very wide field images such as Jim Thommes' image of it and nearby Sharpless 135 that can be found at: http://www.jthommes.com/Astro/Sh2-135.htm .

With no galaxies or asteroids I wasn't going to prepare an annotated image then I found the field contains a rather interesting star-like planetary nebula PN G104+01.0 north of the cluster. I had to label it to allow it to be found. It has a lot of references at SIMBAD, most just catalog entries but some refer to it as containing a large amount of hot dust. That would likely explain its odd color that's very different from what you'd expect a planetary nebula to be. I did find a 1992 paper giving its distance as 10,500 light-years and its diameter as 0.04 light-years. This would indicate it is a very young planetary and explains its star-like appearance. Only the HST can resolve it. I've included an OIII filtered image of it by the HST. The bright stars in the HST image are seen in my image just that most are larger than the planetary in my image while the resolution of the HST makes them much smaller. The nebula itself is overexposed. I didn't try to process the original FITS data. Those interested can find it at the HST Legacy Archive website. The 1992 paper can be found at: http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?1992A%26AS...94..399C&db_key=AST&nosetcookie=1

My image contains a very blue star. Often these are listed at SIMBAD a white dwarf stars or turn out to be quasars. Unfortunately, I could find nothing about this blue star. I've noted it in the annotated image along with the planetary nebula.

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

Related Designations for NGC7261

NGC7265

NGC 7265 is an S0^- galaxy in Lacerta about 220 million light-years from us by redshift. It seems to have a lot of spiral structure for an S0- galaxy. It is a very large galaxy with a diameter of some 235,000 light-years assuming the distance is 220 million light-years. It was discovered by Édouard Stephan on September 20, 1876.

To its east is the strange galaxy UGC 12007. The CGCG describes it as a neutral patchy post-eruptive pear-shaped compact with a very extended halo plus jet (southwest) that lies southwest of a bright star. To me, it is a rather typical barred spiral but one with a very extended halo. It's possible the southwest arm is brighter than the northeast one though it could be an illusion due to the bright star. I certainly don't see it is pear-shaped. Its redshift distance is about 210 million light-years. It is likely related to NGC 7265. A past interaction may have caused its large halo and possible the featureless outer ring around NGC 7265.

The edge-on near the top looks like a small version of NGC 891 but with less blue. It is NGC 7264, an Sb spiral with a redshift of 180 million light-years. Still, it could be a member of the same group as NGC 7265, just one that is currently moving rapidly in our direction due to where it is in its orbit. It was found by Albert Marth on September 17, 1863. Much more distant NGC 7263 was also found by Marth but on September 9, 1863.

UGC 12013 near the bottom of the image left of center is classified simply as a spiral and at 230 million light-years is likely a member of the group. A bit more questionable is NGC 7263 to the northwest corner of my image. Its redshift distance of 270 million light-years puts it possibly a bit too far to be a member of the group. The CGCG says of it: "Pair of red fuzzy elliptical with compact disc and neutral spherical compact (or star). Separation = 13 arcsec [south-east] - [north-west]. Spectrum: Absorption: Ca H and K (+ star)." Several other sources consider it a pair of galaxies. Even my database in The Sky says both are NGC 7263. Still, NED lists only one object here and I agree. The PSF of the northwest object is virtually identical to a similarly bright star nearly due west of the object. No known galaxy in the image has a PSF identical to a star in the image. It is listed as S?.

NED shows one galaxy group, USGC U813 with 9 members at 220 million light-years. This has to be the group anchored by NGC 7265 though no diameter is given. Except for 2 LEDA galaxies redshift data isn't available for any of the other members of the group. Since the annotated image wasn't very dense with identifiable galaxies, all that NED did have identified are shown in the annotated image. Most with a ? for distance as it wasn't available.

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

Related Designations for NGC7265

NGC7282

NGC 7282 is a low surface brightness galaxy in southern Lacerta about 190 million light-years from us by redshift and 180 million light-years by the median of Tully-Fisher measurements at NED. Arp had a classification for "wind effects" that this one would seem to fit into nicely. The field is somewhat obscured by dust in our Milky Way which reddens the galaxy and dims it. I have partly compensated for the reddening. It is always a quandary for me, should I leave it as dust-colored and thus red or try and remove the dust to show its "true" color. Since I used spectral types of the stars in NOMAD's database as a color reference and they tend to be reddened by the dust I end up removing some of the red but since the stars are only seen through some, not all the dust the reddening of the galaxy and a few stars aren't fully removed. Nearby stars in front of any dust are then too blue after the adjustment which is applied to the entire image. Also, some parts of the field may contain more dust than others further altering color. Sometimes I leave them red and other times I compensate to some extent. I chose the latter for this image.

NGC 7282 is listed at NED as SB(r)b with a Seyfert 2 active nucleus. The NGC Project says it is SBb while Seligman says SBb?. I don't see the inner ring that NED's classification sees. I suppose it is referring to the inner arm that are quite unsymmetrical about the core. The galaxy appears to have been drawn out by some encounter though no candidate is seen in my image. The only other galaxy with redshift data is CGCG 531-007 to the lower left near the bottom of my image. Redshift puts it at 200 million light-years so it could very well be related to NGC 7282. But it shows no distortion so is very unlikely to be the cause of NGC 7282's distortion. NGC 7282 was discovered by Édouard Stephan on October 2, 1878. I get a major axis size of 167,000 light-years making this a large galaxy. If an interaction is involved then it likely was smaller prior to the event. CGCG 531-007 is much smaller at about 55,000 light-years. The entire field has some faint nebulosity throughout. My exposure times aren't sufficient to bring them out but for a few faint puffs on the eastern (left) side of the image.

Being in the zone of avoidance there's little on this field. In fact, few of the galaxies are listed in NED or SIMBAD at all. With no data on the other galaxies with many not listed at all, I didn't prepare an annotated image. Transparency when taking the blue frames was very poor. Then conditions improved so I tried again but it was a sucker hole. Those two frames were also badly hit. To get usable blue I combined all four attempts.

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

Related Designations for NGC7282

NGC7292

NGC 7292 is an irregular barred galaxy of the Magellanic type (IBm) located in the constellation of Pegasus. Its distance is rather uncertain. Redshift would say 30 million light-years but at this close distance, redshift is highly unreliable. I found three Tully-Fisher measurements saying 35 million light-years. I'm not sure I trust this method for irregular galaxies of low surface brightness like this one but it does appear a more reasonable answer. Ground based Cepheids would pin down the distance if it were as close as 30 million light years. I found none, indicating it likely is further than that. Hubble hasn't studied it that I found other than to take two images in rapid succession, insufficient for this purpose. In fact, this entire field of view has not been studied in any detail at all. NED lists only one other galaxy and no quasars within 15 minutes of arc of this galaxy. This is by far the lowest total I've ever encountered. It is 2MASX J22283347+3022063 and is a very red galaxy in the image just left of the center of NGC 7292 and up nearly 5 minutes. There's a very orange star below it with another very red galaxy slightly below the star. Nothing else within 15 minutes of arc is cataloged that I was able to find at NED. SDSS hasn't surveyed the area. The galaxy was discovered by Édouard Stephan on September 6, 1872. It is classified as IBm? by Seligman, Irr by the NGC Project and IBm by NED.

I have attached the very noisy "discovery" image from Hubble as it shows the two star clouds at either end of the bar and little else. Not all Hubble images are destined for APOD it appears.

14" LX200R @ f/10, L=4x10 RGB=2x10x3, STL-11000XM, Paramount ME

Related Designations for NGC7292