This
Astrobin Debut Object is a polar ring galaxy located 140 million light years away in the constellation of Virgo at a declination of -11 degrees. The main disk spans 1 arc-minute in our apparent view. This corresponds to a small diameter of 40,000 light years. The perpendicular polar ring is about 120,000 light years in length.
Looking closely, especially in the lower half of the image, you will see numerous parallel light rays originating from below the lower left corner of the image. These rays are from the bright magnitude 1 star Spica, which is one of the 20 brightest stars in the night sky. It lies less than 1 degree southeast of NGC 5122.
NGC 5122 is a fascinating object. Some sources say that we are looking at bi-polar jets emanating from this galaxy, but it looks like a polar ring galaxy (PRG) to me. PRGs are multi-spin galaxies with 2 axes of rotation. The multi-spin is believed to be the result of a galaxy merger, in which the host galaxy accretes stars, dust and gas from a nearby companion galaxy. Sometimes these companions are still present, but typically (as in this case) there are no companions visible. The accreted material forms a large perpendicular ring around the host galaxy. Often the host galaxy appears yellow (older stars) and the accreted ring appears blue (recently formed stars). Unlike other merger results, polar ring galaxies are believed to be a relatively stable configuration, in a quasi-equilibrium state.
My collection of PRGS is
here, and
here is my previous PRG poster.
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