Object name: NGC5548

Designation(s): NGC5548, UGC09165, LEDA140292,

NGC 5548 is one of the first Seyfert galaxies discovered so is very well studied for that. It is found in Bootes. It was the large plumes that drew my attention and I found nothing much on them much to my dismay. I assume that they are the result of a merger with some other system and that in turn has triggered its active and highly variable Seyfert nucleus. Still I found nothing directly saying why there are these plumes. There are several dwarf galaxies in the area indicating it has companions and could have chowed down one or more in the past. Redshift puts it about 240 million light-years distant. A single non-redshift measurement puts it a bit further at 300 million light-years. Using the 240 million light-year distance I measure its size without the plumes at 100,000 light-years. About the size of our galaxy. Including the plumes, it grows to over twice that size at 225,000 light-years. It was discovered by William Herschel on May 19, 1784 and is in the second Herschel 400 observing program. Most visual descriptions describe the core as being stellar in appearance which fits its Seyfert classification. However, my stretch of the core failed to show this unless I applied a linear stretch that left most of the galaxy entirely invisible. Any attempt to bring up the galaxy expanded the core beyond looking stellar.

I moved the galaxy toward the top of the frame in order to pick up the pair of interacting galaxies LEDA 140292 and LEDA 140293. The former has been drawn out with a huge curved plume ending in a brighter section that reminds me of a scorpion with the bright section its stinger. I assume they are interacting. I found nothing useful on them in this regard. LEDA 140293 had no redshift so it is even possible they are two totally unrelated galaxies in the same line of sight. I suppose the \"stinger\" could be the remains of a galaxy that was destroyed by LEDA 140292 and 140293 isn\'t involved but I find this of a low probability. I prefer to think of the two LEDA galaxies as interacting until I learn differently. Without the plume either LEDA galaxy is about 30,000 to 35,000 light-years across. Including the plume, LEDA 140292 is almost 110,000 light-years across. I wish we could convince the HST to take a look at it. The Sloan image (attached) shows the blue object below LEDA 140293 appears to be a second plume hiding behind LEDA 140293 indicating it is likely in front of its western plumed companion.

The field contains quite a few galaxy clusters. The one to the upper left looks a lot like a swarm of red bees around a huge queen bee. While other clusters are at about the same 3.5 million light-year distance their members aren\'t nearly as red nor as bright.

Due to the faintness of the plumes, I tried using 1 20 minute frame for each color rather than 2 10 minute ones to better hide read noise. I don\'t think it helped and the red frame had a satellite I had to clone out. For so little gain it wasn\'t worth it. I suppose two 20 minute color frames might have made a little difference but probably not worth it either. An experiment for the future.

14\" LX200R @ f/10, L=4x10\' RGB=1x20\', STL-11000XM, Paramount ME