This Astrobin Debut Object, also known as UGC 6945, is a set of interacting galaxies located one-half billion light years away in the constellation of Ursa Major at a declination of +36 degrees. To be clear, this object has been posted on Astrobin before but only as a Hubble processed image.

This is one of the smallest Arp objects from our viewing perspective. Each galaxy here is about 15 arc-seconds wide, the same apparent width to us as Saturn currently. This galaxy was classified by Dr. Arp into the category of Galaxies – Material Ejected From Nuclei.

This is a tough object for me to interpret. I thought I understood it from my image: a pair of distant yellow interacting galaxies, and a closer blue galaxy superimposed below. But I have 3 major points of confusion now after checking the distance data and the Hubble image:

1. The distance data shows all 3 galaxies to be at the same distance – about 500 million light years. This distance means that all of the galaxies are about 50,000 light years in diameter. This makes sense for the bottom galaxy, but the structure and color of the top two galaxies is inconsistent to me for that small of a diameter. It would make more sense if these top 2 galaxies were 800,000 light years away, which would imply diameters for them of 70,000 light years.

2. What is that small 4th galaxy at middle right of the Hubble image? It is small but has good structural definition. This galaxy looks much closer to me than the others. I could find no distance information for it.

3. Most strange are the bright blue star clusters throughout the Hubble image. These really look out of place to me, as if they were painted in there. I have never seen such a bright and well defined stream of clusters in an image like this. Their brightness, color and sharpness are inconsistent with that of the galaxies, almost as if this signal was processed separately and superimposed. The star streams follow the structure of ALL FOUR GALAXIES to some extent. The bridge between them is the brightest part and is both blue and purple. So much about this star stream looks odd and out of place to me in the Hubble image.

This may be the only instance where the Hubble image actually confused me more than helped me when trying to interpret my own image.

The object to the right is the near face-on spiral galaxy UGC 6929. This galaxy is 300 million light years away and 70,000 light years in diameter.