alan4908 Posted April 19, 2018 Share Posted April 19, 2018 The image below illustrates what happens when two spiral galaxies crash into one another..... They are now somewhat less spiral shaped than before the crunch and you can also see the debris trail between them. Apparently, they are now heading away from each other. The larger galaxy is NGC4490 (aka the Cocoon Galaxy) and the smaller one NGC4485. Whilst this is an LRGB image, I was quite pleased to see some Ha regions clearly visible. The image represents just over 12 hours integration time and was taken with my Esprit 150. Alan LIGHTS: L:13, R:19, G:20, B:21 x 600s, BIAS:100, DARKS:30, FLATS:40 all at -20C. Link to comment Share on other sites More sharing options...
alexbb Posted April 19, 2018 Share Posted April 19, 2018 Very nice! That's something we don't get to see too often. Link to comment Share on other sites More sharing options...
Galen Gilmore Posted April 19, 2018 Share Posted April 19, 2018 What a sight! Link to comment Share on other sites More sharing options...
Ceph Posted April 19, 2018 Share Posted April 19, 2018 Interesting picture and information. Behind all this beauty lurks destruction and rebirth Great job Alan Link to comment Share on other sites More sharing options...
Demonperformer Posted April 19, 2018 Share Posted April 19, 2018 Superb image of an interesting object. Link to comment Share on other sites More sharing options...
Lars Posted April 19, 2018 Share Posted April 19, 2018 This galaxy pair is also one of the objects in Halton Arp's Atlas of peculiar galaxes as Arp 269 and this a one of the best images I've seen of it! /Lars Link to comment Share on other sites More sharing options...
alan4908 Posted April 20, 2018 Author Share Posted April 20, 2018 12 hours ago, moise212 said: Very nice! That's something we don't get to see too often. Thanks - yes, it doesn't often appear here - maybe because it appears quite small in the sky. 12 hours ago, Galen Gilmore said: What a sight! Indeed. 12 hours ago, Ceph said: Interesting picture and information. Behind all this beauty lurks destruction and rebirth Great job Alan Yes, quite interesting to see all those star forming regions after the collision. 11 hours ago, Demonperformer said: Superb image of an interesting object. Thanks for the comment DP. 11 hours ago, Lars said: This galaxy pair is also one of the objects in Halton Arp's Atlas of peculiar galaxes as Arp 269 and this a one of the best images I've seen of it! /Lars Thanks. Considering it's angular size I was pleased to capture some detail, I also like the variety of the colours ! Alan Link to comment Share on other sites More sharing options...
ollypenrice Posted April 20, 2018 Share Posted April 20, 2018 That is quite outstanding. I'm inclined to desribe both the capture and the processing as perfect. Sky, stars, galaxies... how could they be better? Gorgeous target, and new to me. Also of interest is the fact that this comes from a six inch refractor. I'm coming to the conclusion that this is the most versatile and effective instument in captivity... Olly Link to comment Share on other sites More sharing options...
alan4908 Posted April 20, 2018 Author Share Posted April 20, 2018 18 minutes ago, ollypenrice said: That is quite outstanding. I'm inclined to desribe both the capture and the processing as perfect. Sky, stars, galaxies... how could they be better? Gorgeous target, and new to me. Also of interest is the fact that this comes from a six inch refractor. I'm coming to the conclusion that this is the most versatile and effective instument in captivity... Olly Thanks Olly, I'm glad that you like the image processing. Yes, I have found that my Esprit 150 is delivering the goods particularly well on galaxy images. Combined with the fact that it is virtually maintenance free, it does make a compelling proposition ! Alan Link to comment Share on other sites More sharing options...
Allinthehead Posted April 20, 2018 Share Posted April 20, 2018 Wonderful image Alan. Link to comment Share on other sites More sharing options...
alan4908 Posted April 21, 2018 Author Share Posted April 21, 2018 18 hours ago, Allinthehead said: Wonderful image Alan. Thanks Richard Link to comment Share on other sites More sharing options...
Barry-Wilson Posted April 21, 2018 Share Posted April 21, 2018 Well done Alan - interest in an unusual target and finely captured and processed. How much is cropped here out of interest - what's your imaging scale with the Esprit and your ccd? Link to comment Share on other sites More sharing options...
alan4908 Posted April 21, 2018 Author Share Posted April 21, 2018 4 minutes ago, Barry-Wilson said: Well done Alan - interest in an unusual target and finely captured and processed. How much is cropped here out of interest - what's your imaging scale with the Esprit and your ccd? Thanks Barry. My imaging scale is 0.7 arc seconds/pixel. The image is definitely cropped ! - Since I'm not entirely sure how you quantify a cropped image wrt to the original size.... PS informs me that the original image, including stacking alignment errors, in TIFF format is 3388 x 2712 pixels at 72 pixels per inch = 9188256 pixels. The cropped TIFF is 1113 x 1392 pixels at 72 pixels per inch = 1549296 pixels. So the area cropping factor is 9188256/1549296 = 5.93, which means the cropped image represents c17% of the initial image area. If you take a digital zoom perspective, then the cropped image represents a digital zoom equipment of Square Root (5.93) = 2.4x Alan Link to comment Share on other sites More sharing options...
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