NGC6789

NGC 6789 is a very small irregular galaxy in eastern Draco about 11 to 12 million light-years distant. This was determined by the Tip of the Red Giant Branch method using HST data. Redshift is useless at this close distance and in fact, the galaxy is slightly blue shifted rather than redshifted.

Its core region is full of bright blue star clouds while the entire galaxy is blue. NED classifies it as Im but the one main paper http://arxiv.org/pdf/astro-ph/0102452v1.pdf I found on it argues it is a Blue Compact Dwarf. It just doesn't seem as dense as the other BCD galaxies I've imaged but maybe that isn't a requirement. Assuming the distance is 12 million light-years I get a size of about 4,800 light-years. That certainly is a dwarf!

The HST has taken some images of it but none have been using filters that could be used to create an image anywhere close to the real color. One quickly processed image from Wiki is at https://upload.wikimedia.org/wikipedia/commons/5/54/NGC_6789_hst_09162_R814B606.png but it doesn't say what filter was used for it. Since near IR I band is useful for TRGB distance measurements this may be the frequency used. That would explain the lack of resolution of the blue star clouds I picked up as this would be picking up much cooler stars best. The paper cited above says some 15,000 or so stars were resolved by the HST image

The galaxy was discovered by Lewis Swift on August 30, 1883. This part of the sky is poorly studied for galaxies. NGC 6789 is the only one in the field with any distance data. Therefore I didn't prepare an annotated image.

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

Related Designations for NGC6789

NGC6792

NGC 6792 is a very large, possibly "red and dead" spiral in northeastern Lyra. It is a bit over 200,000 light-years distant by redshift and while Tully-Fisher estimates put it slightly further the agreement is quite good. I measure its size at about 150,000 light-years. NED and the NGC project classifies it as SBb while Seligman says SBb?. I'm not sure why the question mark. It has a very odd rotation curve that is centered on a point well south of the core. I didn't find any ideas why this was the case. The faint spiral arms are rather distorted, possibly due to this odd rotation curve. Could this be why it appears to be a "red and dead" galaxy? Is this appearance only due to it being heavily reddened by our galaxy's dust? I doubt it, it has places on its outskirts appear slightly blue.

It was discovered by J(acob) Gerhard Lohse in 1886. While he is credited with 17 NGC objects, only 3 were galaxies. 11 were single or multiple stars and three can't be found. An 18th object turned out identical to NGC 4319 discovered by William Herschel 89 years earlier. His is not a stellar record, or is it too stellar? While there is are craters on both the Moon and Mars called Lohse they are named for Oswald Lohse who studied surface features of some planets though, of course, didn't know of Mars' craters. While both were German astronomers I don't think they were related.

Being in the Zone of Avoidance no other galaxy in the field had any redshift data. Also, there were no asteroids in the image so I it didn't warrant an annotated image.

14" LX 200R @ f/10, L=4x10' RGB=2x10', STL-11000XM, Paramount ME

Related Designations for NGC6792

NGC6801

NGC 6801 is a rather odd spiral in northeastern Cygnus. NED classifies it as SAcd, The NGC Project says Sc while Seligman says Sc?. Note how two arms curve out of the core to the south then turn and go straight to the edge of the galaxy. The northern one seems to suddenly turn north and sort of follow the edge of the galaxy but again in a straight line. I think this more an illusion due to a small field star in our galaxy and a star knot in the arm defining a line that isn't there. But the part coming out to the edge certainly is straight. Arp had a classification for spirals with a heavy arm. Often this was straight as in the most famous example, M101. In fact, the one in M101 does go out straight then bend at about a 75 degree angle and continue on straight until it again bends at about 60 degrees and continues on straight yet again. These two arms aren't heavy but they sure are straight.

NED's redshift puts it some 190 million light-years distant. But its 9 Tully-Fisher measurements range from 143 million to 192 million with an average of 166 million and a median of 152 million. So roll a 10 sided die and see what comes up. Using the redshift value it is about 80,000 light-years in diameter. A reasonable value for a spiral galaxy for whatever that is worth. The closest measurement makes it 60,000 light-years across, also reasonable. Being in the Zone of Avoidance it isn't well studied so I don't expect this issue to be resolved anytime soon.

The galaxy was discovered on August 5, 1886 by Lewis Swift. I've not tried to view it visually. Steve Gottlieb's description at the NGC Project calls it "faint" in his 17.5" scope so it would be difficult at magnitude 13.9 in my 10" scope used for my visual work.

Though the galaxy had a supernova (well it was still preliminary when I took the image) which I've marked in the annotated image. It is thought to be a type II SN so not all that useful for determining distance. That may explain its somewhat red color. I'd expect it to be blue but some Type II explosions result in some H alpha which might be causing the reddening. Or it's just due to looking through the dust of our galaxy as this region is very dusty. But on May 21, 2011 a type Ia, SN 2011df, blew in it. Yet I didn't find it had been used to calculate a distance to this galaxy. It has long since faded away. It was located just under the "19" in the label for the new supernova. Thus well outside the visible disk of the galaxy indicating it is much larger than I'm measuring it.

I didn't know of the supernova when I took it. Only a few weeks later when I was reviewing the frames to make sure I didn't need to retake any (weather has been so bad I've needed a lot of retakes during this period) I saw a star that didn't belong. A check of David Bishop's supernova pages showed me it was discovered a month before I took my image. I see it is now officially SN 2015af.

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

Related Designations for NGC6801

NGC6802

NGC 6802 is a type III1m open cluster in Vulpecula. It was discovered by William Herschel on September 22, 1783. It's not in either H400 program. WEBDA puts the age of the cluster at about 3/4 of a billion years. Rather old for an open cluster as tidal forces usually rip them apart faster than this. Could its elongated shape be due to tidal forces? I doubt it but found nothing on this either way. Its distance is about 3,700 light-years according to WEBDA and it is reddened by nearly a magnitude. Still, it has blue stars. Its main claim to fame is that it is on the end of the "Coathanger" an asterism that looks just like its name. It is located in southwestern Vulpecula.

This is another of my very early images when I did no research and my imaging and processing skills were nearly non-exist.

14" LX200R @ f/10, L=6x5' RGB=3x5'x3, STL-11000XM, Paramount ME

Related Designations for NGC6802

NGC6804

NGC 6804 is a planetary nebula in Aquila, one of many in the constellation. It was discovered by William Herschel on August 25, 1791. It is in the second H400 program. My notes from that were lost in the move to Minnesota. I've not looked at it visually since.

Distance estimates to planetary nebula tend to be guesses more than measurements. NOAO puts it at 4,200 light-years. The eastern side seems flattened. Some papers say this is due to its interaction with the interstellar medium.

This is another early image from 2007 when I did no research so the above is all I found easily. I will try and update this as time permits.

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

Related Designations for NGC6804

NGC6813

NGC 6813 is a small nebula in northwestern Vulpecula about 2.25 degrees southeast of Albireo at the head of Cygnus the Swan. That puts it well into the Milky Way. Even after greatly reducing the stars it is still somewhat lost among the stars. I find very little on this little guy. Also, I failed to note how it got onto my to-do list. I must have had a reason but apparently, I never wrote it down and now I have no idea why I have an image of it.

It isn't a Herschel 400 object as it was one he missed. It was discovered on August 7, 1867 by Albert Marth. While cataloged as an emission nebula some places, Simbad calls it "Interstellar matter". It doesn't have the pink color typical of emission nebula due to the ionized hydrogen and oxygen lines they emit. It does, however, appear to be the birth ground of new stars as it hides a star cluster seen only in infrared light. I found only one amateur color image and that one shows it typical H alpha pink but that's not what I got. Also if you combine the red and blue POSS plates using pseudo green it comes out orange. My red frames were severely hit by fog. I had to boost them by about 5 times the normal adjustment needed at this altitude. If that wasn't enough that could be why I'm not getting typical H alpha color but for the fainter outer parts. I balanced based on the spectral class of the brighter stars in the image or their B-V values. The brighter stars seemed more red challenged than the dimmer stars for some reason. Since the nebula covers a wide brightness range its color is rather suspect. I should have tried for better color data but didn't discover the problem until it was too late to get the data this year.

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

Related Designations for NGC6813

NGC6814

NGC 6814 is a face on spiral galaxy about 60 million light-years away in the southern Aquila. Not a constellation that jumps to mind when galaxies are mentioned. I no longer remember what caused me to put it on the to-do list. Possibly it is the somewhat extended northern arm pointing west then southwest. Or maybe that the arms are mostly segments giving some a split arm look Arp cataloged. NED classes it as SAB(rs)bc with HII emission and a Seyfert galaxy. Various sources disagree as to what class of Seyfert it is. NED says 1.2, notes say 1, 1.5 and 2. The NGC project on the other hand classes it as Sb+ I, I don't understand the I at all. Usually, that means "irregular" but I can't see it applying here. NED sees a bar but the NGC project doesn't. Who do you believe? I'm hard pressed to see a bar but many notes indicate it has a short wide one buried in the bright oval core. In any case, the many spiral arms don't seem related to the core at all. They seem to just start at random somewhere near the core then get bright as they move out beyond the end of the oval core region. Edit: It was discovered by William Herschel on August 2, 1788. It's in the second H400 program. I wasn't images this back in 2011 when this was taken so that's now why I imaged it. That's still a mystery.

This one is at -10 degrees declination which puts it in my summer gunk so the image isn't as clear as I'd like. It's rare to get decent seeing in this part of the sky from my location. The temperature difference between the warm water and rising water vapor and the cool night air make for some poor seeing conditions as well as transparency.

There are no other galaxies in the image that NED has any distance data for and only a few are even identified. All that are IR galaxies from the 2MASS survey. For this reason, I didn't prepare an annotated image. There are two asteroids in the image, both above NGC 6814. The easiest to spot is near the top right of center and is a short streak with a hint of red at the lower left end and a hint of blue at the upper right end. Nothing was bright enough in the luminance image for any part of the green trace to show up. It would be beyond the red as I took the data blue, luminance, red and green. Thus the asteroid is in direct prograde motion. It's rare for me to catch one in this part of its yearly path. It is (12508) 1998 FZ113 at magnitude 17.2. The other asteroid is down and to the left of the first and very hard to spot as its trail is only 3.8" of arc long. In is rather alone between stars directly above the left edge of the bright portion of NGC 6814's arms two-thirds of the way to the top. It is in retrograde motion but and moving down at a 45 degree angle (left to right). I must have caught it just after it reversed into retrograde motion for it to be moving so slowly in the sky. It is (44504) 1998 XX34 and is estimated to be 18.3 magnitude.

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

Related Designations for NGC6814

NGC6821

NGC 6821 is a rather disorganized barred spiral galaxy in southern Aquila about 60 million light-years distant both by redshift and Tully-Fisher measurements. It is classified as SB(s)d: HII by NED. The NGC project says SB(rs)Sd. I don't know how to decipher that second "S" unless it is a misprint. Seligman classifies it as SBcd?. They do agree it is a barred spiral and it does show a bar-like structure but I see no nucleus. de Vaucouleurs says in his 1964 "Reference Catalogue of Bright Galaxies" "Bright bar: 0.2 arcmin x 0.06 arcmin. No definite nucleus. Faint asymmetric spiral structure. Poorly resolved." IT was discovered by Albert Marth on August 8, 1863. It is sometimes considered a pair with MCG -01-50-001 which is a flat galaxy 2MFGC 15085 just off the right edge of my image. I had intended to use coordinates to pick up both but somehow centered on NGC 6821 instead. That may mean a reshoot in the future.

Being well within the Zone of Avoidance there are few galaxies in the field with any information on them. I've annotated all with redshift data as well as galaxies that made the LEDA catalog even if they had no redshift information. Due to obscuring dust in our galaxy this image doesn't go very deep.

Being a bit below -06 degrees every frame contained many geostationary satellites. Many trails overlapped so many times no rejection software could deal with them. Nor could my manual method I use when I have only 2 frames. Thus I had to resort to cloning to remove them. Since the field is just on the north edge of the belt as seen from my latitude all were in the very bottom of the image. Since they went through a lot of faint nebulosity this made the cloning all the more difficult. I hope I haven't distorted things too much.

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

Related Designations for NGC6821

NGC6822

This is a shot of a galaxy in our local group, NGC 6822, commonly known as Barnard's Galaxy as he discovered it with a 6" refractor over 120 years ago. Located about 1.7 million light years away it is a dwarf galaxy. Oddly, it shows little rotational motion, especially in the outer regions. It is full of bubbles blown by newly formed star clusters. The biggest and brightest is actually called the Bubble Nebula, not to be confused with a very different Bubble Nebula formed by a dying star in our own galaxy that I've run here twice before. This is caused by a cluster of super massive, super hot stars that formed out a a cloud of hydrogen gas. Then their intense light blew an ever expanding bubble in the remaining hydrogen. In a few million years the bubble will have expanded so much and so many of the stars that formed it will have gone super nova that it will vanish. This bubble is huge compared to those known in our galaxy. Most of which are 30 or so light years across. This one is about 500 light years in diameter! To be illuminated by stars 250 light years distant you know those stars are super bright!! Actually, this galaxy has many such bubbles, far more than most dwarf galaxies have. NGC 6822 is thought to be very similar to the galaxies that first formed in our universe and which then combined to form more massive galaxies such as our own. Though why it still has so much dust and gas left is somewhat of a mystery. Since we see this galaxy through the dust of our own galaxy it is greatly dimmed and reddened. It would be far bigger and brighter if it was located in a direction looking out of our galaxy rather than into it.

The Hubble Space Telescope can only look at a very tiny part of this object at a time. It studied two of the HII star forming regions, Hubble X and Hubble V. Hubble X is at the upper left of the somewhat faint pink bubble at the top and slightly left of center of the galaxy. It appears as a bright white star at the upper left edge of the ring. In fact, it is a star cluster tightly surrounded by nebulosity, all of which overexposed in my shot to make a white blob. The bubble is apparently an entirely different object unrelated to Hubble X. You can see Hubble's picture of it in false color at:
http://apod.nasa.gov/apod/ap010216.html

Hubble V is to the right of Hubble X about halfway to the big bubble nebula. A bright star overpowers it to the left of it. Then the cluster of stars that causes it to glow drowns out the much fainter nebula at my low resolution compared to Hubble working above our atmosphere. So only a hint of pink is seen at: http://apod.nasa.gov/apod/ap011225.html This time the colors are close to correct.

You can read more on it at:
http://www.messier.seds.org/xtra/ngc/n6822.html
The photo with this page though seems overly blue but it was taken using film which does often respond very differently than reality in long exposure photos. Also, this page puts the distance at 1.8 million light years which is an old estimate best as I can determine. Some links at this site are broken.

Related Designations for NGC6822

NGC6823

Technically NGC 6823 refers only to the star cluster in this image. NGC 6820 is often cited as the red emission nebula but that is SH2-086. The position of NGC 6820 is close to the knot in the lower right of my image. It is most likely the real NGC 6820.

NGC 6822 was discovered by William Herschel on July 17, 1785. Apparently, he only saw the star cluster. It is in the original H400 program. My notes indicate in my 10", even though I listed the night as good, I never saw the nebula nor most of the cluster. I saw only the very brightest stars in the center of the cluster not a field of stars my image shows. Maybe the night wasn't so good after all. I made no mention of NGC 6820 though that wasn't on my Tiron atlas so I had no idea it was there. Still, it didn't catch my eye. The cluster is less than 7 million years old, some say less than 2 million so possibly still forming stars from the gas we see as SH2-086. The stars aren't all that blue in my image. This is likely due to my inability to properly color balance my very early images. I need to retake this one.

NGC 6820 was first seen by Albert Marth on August 7, 1864. Is the knot a separate object or part of SH2-086? It appears to house a protostar when seen in the 2mass survey. I found no distance data on it. While my white light image doesn't show it connected to SH2-086 H alpha images do. It appears all three objects are likely part of the same complex.

I tried to force this image through many subs rather than adding H alpha data. This is why the image is so poor. I need to redo this one. The data was taken back in 2006 when I had no idea what I was doing and processed using 8 bit software not up to the task. I was so disappointed in how it turned out I never let anyone see it until now. While I have some that came out even worse than this one I knew that so never even tried to process the data. Most have since been retaken but for this one.

14" LX200R @ f/10, L=20x10' RGB=4x10', STL-11000XM, Paramount ME

Related Designations for NGC6823