DescriptionImages

Object name: NGC6691

Designation(s): NGC6691,

NGC 6691 is a spiral galaxy located in Draco some 260 million light-years from us. Arp has a category in his atlas for 3 armed spirals. All three he included are really two-armed spirals with a major spur off one to make the third arm. Thus, I include this one as falling into the same category. It has two main arms coming off the bar and a large spur overlaying one of those arms that first goes north on the western side of the galaxy they a second spur comes off it going northeast. Much smaller spurs are seeing coming off the other arm. The galaxy to the south is listed in a note at NED as being a companion. This field is so poorly studied it has no catalog entry in NED. All other galaxies in the image that NED identifies are from the 2MASS IR catalog which only picks up galaxies bright in 2 micron IR radiation. The companion apparently doesn't have enough. It was discovered by Lewis Swift on August 16, 1884.

In the cropped and enlarged image, I've put NGC 6691 well off center to catch, in the opposite corner, two or maybe three galaxies. The two brightest are in the 2MASS catalog as 2MASX J18400484+5545142 and 2MASX J18400579+5545152. I can't tell for sure if the former is separate from the disk galaxy behind it or just a very bright core. I tend to think it is just another elliptical/S0 like the other one to the east and the disk object is a third galaxy whose core is mostly hidden by the 2MASS galaxy. NED is of no help here listing no size for either of the two galaxies.

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