This
Astrobin Debut Object is a pair of galaxies located in the constellation of Cetus at a declination of -9 degrees. In his
Arp catalog, Dr. Arp classified this object into the category of Elliptical and Elliptical-like Galaxies Close to and Perturbing Spirals.
The large deformed face-on spiral is NGC 191, located 280 million light years away. This magnitude 13 object spans 1.5 arc-minutes in our apparent view, which corresponds to a Milky Way like diameter of 120,000 light years. The core of the galaxy is offset slightly to the upper right. The arms form a pseudo outer ring which is shaped a bit like a prolate spheroid (i.e., an American football).
The small edge-on spiral is IC 1563. All of the commentary I have seen, including Arp’s, assumes that this is a small companion. SIMBAD shows distance data which confirms that. But I question whether it is a true companion. If this galaxy is also 280 million light years away, it is only 40,000 light years in diameter. That is too small in my experience for such a bright, well defined spiral structure with a faint surrounding galactic halo. Plus, this small “companion” is completely undisturbed.
SIMBAD also has a second set of data which suggests that IC 1563 is much further away, at 630 million light years. Such a distance would put the diameter at 95,000 light years, which makes much more sense to me. So I think that these 2 galaxies are not companions, just a nice line of sight pair for us.
So then, what is causing the disturbance of NGC 191? I think it may be the small dwarf galaxy seen as a faint smudge to the bottom right of NGC 191, at the edge of its disk. But there is no distance information available for this small object, so it is impossible to confirm that it is a companion.
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