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IC 284 in dust
As usual. All embedded links are spam and have absolutely nothing to do with astronomy or my post. Please ignore the crapola.
IC 284 is a rather low surface brightness spiral in Perseus. Red shift puts it at 110 million light-years distant while Tully Fisher distances have two at 79 million light-years and one at 121 million light-years. Assuming the redshift distance it is a large spiral at 130,000 light-years across. It is classified as SAdm at NED and SAd? elsewhere. A Sd galaxy is often quite large due to the spread out arms so this may be reasonable. If the nearer Tully Fisher distance is used it is a more normal 93,000 light years across. The larger estimate makes it 143,000 light-years in diameter. Throw a three sided die and pick one. It was discovered by Lewis Swift on October 27, 1888. The apparent companion V Zw 319 is a red spherical compact galaxy surrounded by a circular halo with a bar according to the CGPG. Seligman says it is behind IC 284. I can't really tell which side it's on from my image. The eastern half is easily seen making it appear in front but there are other similar galaxies in my image at twice the distance of IC 284. It could be another from that group. In any case there's no sign of interaction so it could be much closer or further or nearly the same distance. Unfortunately there's no redshift data on it. The other IC galaxy is IC 288 listed as S? by NED and Sab? by Seligman. It too was discovered by Lewis Swift but on October 31, 1888, 4 nights after he found IC 284. The field around IC 288 has a large arc of nebulosity. At first I thought there was something wrong with the image. The flat had worked well with other images so was there some reflection causing this arc in the light frames? The Sloan image shows pieces of this nebulosity but not the entire arc I am seeing. Still I'm pretty confident it is all a real feature. I'll leave it to other imagers to take a deep image at a wider field and pick up this dust. I was unable to locate any nebula in the area in SIMBAD so it may be galactic cirrus (IFN). If so it is unusually bright. Two faint asteroids made an appearance. The fainter one barely survived the JPG process but if you enlarge the image you should be able to just see it. This area of the sky is poorly studied for galaxies. Only the 2MASS survey covers this are. Since it only picks up those seen at the two micron wavelength deep in the IR part of the spectrum many galaxies with little 2 micron emission aren't cataloged. Since so few were I broke my usual rule of not showing galaxies without red shift as well as my rule of not showing those only identified by their position in the sky. There were so few these didn't clutter up the image as normally would happen if I did this with a typical field of galaxies. Several I wanted to know more about didn't make the 2MASS so aren't cataloged. I marked those with a question mark though many other overlooked galaxies could also get that question mark label. 14" LX200R @ f/10, L=4x10' RGB=2x10' STL-11000XM, Paramount ME Rick Last edited by WA0CKY : April 19th 15 at 07:14 AM. |
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IC 284 in dust
WA0CKY wrote in news:WA0CKY.f790dc9
@spacebanter.com: As usual. All embedded links are spam and have absolutely nothing to do with astronomy or my post. Please ignore the crapola. I just went over to spacebanter and took a look at the last few dozen postings of yours. I don't see any extraneous links. Although you mentioned in at least one post that you've edited them out later. But if they are there they must be inserted after the post is forwarded to usenet because I never see them here. If you see these links in a posting, let me know. I'll take a look myself and see what they are to help you determine the cause. The problem is, I know that there are browser hijacks (masquerading as 'useful' plugins) that cause this. They are essentially trojan horse viruses for your browser. If you have one of these, you will see these links, but not anyone else. Further, I see you replied to my previous comment on this. I never saw it here on usenet. Looking closer I see other replies that you've replied to that don't show here either. Looking even closer, this doesn't appear to be a a consistent problem. Sometimes they do get through, but sometimes not. So, if you reply to this, there's a possibility of me not seeing it. Brian -- http://www.earthwaves.org/forum/index.php - Earth Sciences discussion http://www.skywise711.com - Lasers, Seismology, Astronomy, Skepticism Sed quis custodiet ipsos Custodes? |
#4
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IC 284 in dust
Rick,
the galaxy itself would be worth an image and the dust makes it even more worthy of attention. Very nice. Stefan "WA0CKY" schrieb im Newsbeitrag ... As usual. All embedded links are spam and have absolutely nothing to do with astronomy or my post. Please ignore the crapola. IC 284 is a rather low surface brightness spiral in Perseus. Red shift puts it at 110 million light-years distant while Tully Fisher distances have two at 79 million light-years and one at 121 million light-years. Assuming the redshift distance it is a large spiral at 130,000 light-years across. It is classified as SAdm at NED and SAd? elsewhere. A Sd galaxy is often quite large due to the spread out arms so this may be reasonable. If the nearer Tully Fisher distance is used it is a more normal 93,000 light years across. The larger estimate makes it 143,000 light-years in diameter. Throw a three sided die and pick one. It was discovered by Lewis Swift on October 27, 1888. The apparent companion V Zw 319 is a red spherical compact galaxy surrounded by a circular halo with a bar according to the CGPG. Seligman says it is behind IC 284. I can't really tell which side it's on from my image. The eastern half is easily seen making it appear in front but there are other similar galaxies in my image at twice the distance of IC 284. It could be another from that group. In any case there's no sign of interaction so it could be much closer or further or nearly the same distance. Unfortunately there's no redshift data on it. The other IC galaxy is IC 288 listed as S? by NED and Sab? by Seligman. It too was discovered by Lewis Swift but on October 31, 1888, 4 nights after he found IC 284. The field around IC 288 has a large arc of nebulosity. At first I thought there was something wrong with the image. The flat had worked well with other images so was there some reflection causing this arc in the light frames? The Sloan image shows pieces of this nebulosity but not the entire arc I am seeing. Still I'm pretty confident it is all a real feature. I'll leave it to other imagers to take a deep image at a wider field and pick up this dust. I was unable to locate any nebula in the area in SIMBAD so it may be galactic cirrus (IFN). If so it is unusually bright. Two faint asteroids made an appearance. The fainter one barely survived the JPG process but if you enlarge the image you should be able to just see it. This area of the sky is poorly studied for galaxies. Only the 2MASS survey covers this are. Since it only picks up those seen at the two micron wavelength deep in the IR part of the spectrum many galaxies with little 2 micron emission aren't cataloged. Since so few were I broke my usual rule of not showing galaxies without red shift as well as my rule of not showing those only identified by their position in the sky. There were so few these didn't clutter up the image as normally would happen if I did this with a typical field of galaxies. Several I wanted to know more about didn't make the 2MASS so aren't cataloged. I marked those with a question mark though many other overlooked galaxies could also get that question mark label. 14" LX200R @ f/10, L=4x10' RGB=2x10' STL-11000XM, Paramount ME Rick -- WA0CKY |
#5
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IC 284 in dust
WA0CKY wrote:
Usenet doesn't allow embedded links as it is pure text so they don't appear there but a few weeks ago Spacebanter started inserting advertising links. I can't edit them out, all I can do is change wording so a word or phrase doesn't turn into an ad. Sometimes that's not possible or so awkward I don't do it. Two were inserted in this post. I hope to drop SpaceBanter shortly as they are too unreliable as you have noticed. I have no other access to Usenet so will move totally to the internet which is much more reliable for images anyway (well not SpaceBanter as they keep losing posts. I copied this from spacebanter, since your reply didn't make it to usenet. Well, yes, no embedded links since usenet doesn't support HTML directly. But from your description, it sounds like the ad links are applied at page rendering time and not actually part of the message itself, so those wouldn't be forwarded to usenet. For usenet access, I currently use Altopia. Plans start at $6/month and that's enough for my needs. I've only used them a for a few months now but have had zero problems so far. I've been usenetting for... egads... 20 years or so(!) with various providers. I agree it's not as permanent as a website for archiving images. If it's that important to you for publishing them online, maybe set up your own website? Or use an image hosting service and post links? Or a combination? There are options. It just depends on what your needs are. Actually, considering the quality of your images plus the descriptions you give, I think it would be awesome if you could set up your own website. It could become quite a reference source. Brian -- http://www.earthwaves.org/forum/index.php - Earth Sciences discussion http://www.skywise711.com - Lasers, Seismology, Astronomy, Skepticism Sed quis custodiet ipsos Custodes? |
#6
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I think of it from time to time but with nearly 1300 objects, many having no simple name like an NGC IC or Messier number I'm at a loss how to make it very easy to navigate or organize. My internet connection is very slow as I live in the boonies of a northern forest with a population of less than one person per square mile. This makes running anything but phone lines very expensive and wireless can't pay with only three households in 36 square miles having even a computer. Satellite is blocked by neighbor's trees and even if it wasn't from reports from the other two that tried it not worth the high cost. So just uploading the files would take weeks or a 40 mile trip to the library with its high speed WiFi but they have so much demand for it they allow only limited times unless you get lucky and only a few dozen show up to use it. They limit to 24 users on at any one time and if another shows up and you've been on over 30 minutes you have to wait until all have had their 30 minutes before you are allowed back on. Keeps the speed up but a major pain.
So so far it isn't happening. And the collection is growing by one more image nearly every other day. About the fastest I can process them and I'm now processing last November's images so am a ways behind. Finding time is the other issue. Rick Quote:
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#7
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IC 284 in dust
WA0CKY wrote in news:WA0CKY.f7e53c8
@spacebanter.com: Skywise;1292842 Wrote: WA0CKY wrote: Actually, considering the quality of your images plus the descriptions you give, I think it would be awesome if you could set up your own website. It could become quite a reference source. Brian I think of it from time to time but with nearly 1300 objects, many having no simple name like an NGC IC or Messier number I'm at a loss how to make it very easy to navigate or organize. My internet connection is very slow as I live in the boonies of a northern forest with a population of less than one person per square mile. Ahhh...good ol' dialup. I can understand that. Wasn't too long ago I got away from it myself. Trying to download linux disc ISO's is really fun. And for you, it's worse, as upload speed is even slower. Anyway, that does really limit things. Even the task of setting up a website would be cumbersome. BTW, this one made it to usenet. Brian -- http://www.earthwaves.org/forum/index.php - Earth Sciences discussion http://www.skywise711.com - Lasers, Seismology, Astronomy, Skepticism Sed quis custodiet ipsos Custodes? |
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