Cepheus - Arp 25 (114) and SHK 175

[Mike JW]

Arp 25 - NGC 2276 is an intermediate spiral – SABc (rs). It is transitioning to a ring structure? It is about 105 million lyrs away and Arp classified it as a galaxy having one heavy arm. Its lopsided appearance is likely due to interacting with its neighbour, NGC 2300 - E-SO (an elliptical/lenticular). The interaction has triggered large amounts of star formation. There is a suggestion that the starburst activity could be caused by 2276 eating up a dwarf galaxy. Chandra located 16 X-ray sources of which 8 are ultra-luminous (ULX), indicating massive star formation regions. These areas are pushing gas outwards (ram pressure) and are likely to be a significant cause of the disruption to the galaxies shape. Some folk think ram pressure is a greater disturbance to the galaxy shape than tidal interactions with NGC 2300. An intermediate black hole was also discovered.

See https://chandra.harvard.edu/photo/2015/ngc2276/

NGC 2276 is also a member of Arp 114 (2276 and 2300). I also managed to squeeze into the shot, UGC 3661.

 

 

SHK 175 is very close to Polaris and yes we all regularly look at Polaris and maybe the ancient cluster NGC 188 so what pleasure to view something different (SHK 175 and also SHK174)

I never know before hand what a SHK cluster is going to look like. Also I can never be sure if the GOTO will have the faint SHK in the centre of the fov. Thus when this appeared on the screen I just knew it had to be the target - an almost perfect circle - freaky- then I spotted its tail. 10 members in total.

Mike

 

 

[Bill S]

Good ones, Mike. Really clear look at NGC 2276. I find it quite a hypnotic object to gaze at in your image. The more you look the more you see.

You did very well to find and snap SHK 175. I will have to have a go at some of the ones you've told us about recently. They'll be a bit of a challenge.

I've been looking at various objects over the last few days. (Lots and lots ) These have also included some objects in Ursa Minor. One object I looked at was NGC 3172 because I came across it Harrington's Cosmic Challenge book. It's in there as Challenge 135 mainly becasue it's the closest NGC object to Polaris. He says that John Herschel named it Polarissima. I've also seen it called Polarissima Borealis. It's classified as S?. Not a very photogenic object.

 

Bill

Edited March 28, 2020 by Bill S

[Mike JW]

Hi Bill, I too have kept having a look at 2276. I have a cropped image as well which reveals subtle detail.

Your 3172 is totally new to me - Sky Safari suggests it is SO.

I shall pop this onto my endless lists.  Mike