Arp 145 falls into the same Arp category as Arp 144, "Spiral galaxies with companions on arms: Small, high surface brightness companions", but sure looks entirely different. It's rather impossible to know exactly what happened in the case of Arp 144. In this case what is going on is more obvious. This is a case of a direct hit by an elliptical galaxy (lower left) on a near face on spiral galaxy (upper right). It punched a hole in the spiral right near the core which probably is the reddish blob at the 5:30 position using the hole as the center of the "clock". The two galaxies carry the same designation UGC 1840. The one with the hole is classed as Im pec Ring B same as the NGC 7828 above though they look far different. The other which does rather resemble its counterpart above also has the designation of S0 pec Ring A They are located at about the same distance as Arp 144, 240-250 million light years. But are located at the east end of Andromeda thus much higher in my sky. Arp's photo of these two is at:
http://nedwww.ipac.caltech.edu/level...ig_arp145.jpeg
Like the field of Arp 144 there has been no useful -- to us -- survey of this region, just the 2MASX IR survey and it found few IR galaxies in this field. It doesn't include redshift data just photometric values. Most aren't cataloged at all, including the interesting elongated one above and a tad left of the pair. Only those picked up on the 2MASS infra red survey are cataloged and that one apparently doesn't emit enough IR light to make the catalog. So it remains anonymous.
14" LX200R @ f/10, L=4x10' RGB=2x10', STL-11000XM, Paramount ME.
Full image:
http://www.spacebanter.com/attachmen...tid=2451&stc=1
Rick
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