This Astrobin Debut Object, also known as UGC 2812, is a collisional ring galaxy located 0.5 billion light years away in the constellation of Eridanus at a declination of -2 degrees. This galaxy was classified by Dr. Arp into the wonderfully named category of Galaxies – Adjacent Loops. I really enjoy looking at collisional ring galaxies – my collection of them is here.

Arp 219 is at the center of the image. The main galaxy is magnitude 14.9 UGC 2812 and the tiny galaxy slightly below and left is magnitude 18.4 2MASX J03395491-0207241. UGC 2812 spans 50 arc-seconds in our apparent view and has a diameter of 120,000 light years.

I am fascinated by so many aspects of this object:

- The star stream arcing above and to the left of the main galaxy
- The contrasting yellow core and blue star formation areas
- The beautiful and well-formed loop below the galaxy

So what is causing the star stream and the beautiful loop? I don’t think it is the tiny galaxy “companion”. There is no distance information for this tiny galaxy. To be at the same distance, this galaxy would be only 30,000 light years in diameter. It looks too well formed to be that small. Plus, I don't see any distinct star streams connecting the two galaxies. So I think the tiny galaxy is far in the distance, a billion miles or more away.

The face-on grand spiral galaxy above and left is UGC 2814, located 430 million light years away. This object is also too far away from the Arp object to be causing the disturbance.

The disturbance galaxy could have been a “hit and run” culprit who has since left the frame. But I believe that the disturbance galaxy was a small companion who is now in the process of being absorbed by the main galaxy. One of the bright blue regions in the main galaxy could be the former core of this companion.

Before leaving this image, don’t miss the fantastic small face-on grand spiral galaxy (2MASX J03392591-0201341) at the top right edge of the image.