The object Arp 278, visible in Pegasus, is made up of two colliding spiral galaxies: NGC 7253 A and B. The galaxies were discovered by the German astronomer Albert Marth in 1863. They are located 238 million light years from Earth. The interaction has transformed them into “starburst galaxies,” with bright knots of star formation inside. The pair occupies 2.6 x 1.8 arcmin. NGC 7253A is the one located to the northwest, magnitude 14.4, 1.7'x0.5', probably a barred spiral. NGC7253B is a weaker and more irregular spiral, magnitude 15, and extension 1.6'x0.5'. There is a compact radio source in the core of NGC 7253A, and a faint, diffuse radio source in NGC 7253B. The galaxies are really close to each other, in the process of colliding. You can see a clear deformation of the tails and, as Arp already observed, “diffuse material between the galaxies.” On November 23, 2002, Mike Shwartz discovered a type Ia supernova of magnitude 16.8 in NGC 7253B (SN 2002 jg). I have superimposed Kopernik's image of said supernova on my photograph, and I have not found anything relevant in its position. I took the photograph on 9 nights in December 2023 and January 2024, with 11h 21m exposure in LRGB, with a Meade ACF 12” f/8 tube and ZWO ASI 2600M camera. The seeing was not ideal for such a small object, but the results were better than expected. It is a weak object, but very accessible for photography, and I got a good signal with exposures of 60” in L and 180” in RGB. The active interior of both galaxies and the deformations produced by tidal forces can be clearly seen.
The first wide crop was
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