In the mid-1960’s astronomer Halton Arp produced a catalog of peculiar galaxies. To astronomers, “peculiar” galaxies are those that are not conventionally shaped. They aren’t perfect spirals or ellipticals. He made this catalog in the hope that it would help the quest to understand galaxy formation and evolution over time. This image is of the 286th galaxy in his list.

Arp 286 is the largest galaxy in the image and it’s also known as NGC 5566. It was discovered by William Herschel (who seems to have discovered half of what we look at) back in the late 1700’s. The galaxy above and to the right is NGC 5560 and below and to the right is NGC 5569.

This data isn’t quite deep enough to really show how secular the galaxy it is but there are definite tidal distortions to the fringes of the galaxy and what looks like a tidal tail from NGC 5560 connecting with 5569. There are also a lot of tiny, very distant background galaxies in there.

The large galaxy is estimated to be about 66 million light years away and about 150 thousand light years across making it much larger than our Milky Way. NGC 5560 to the upper right is likely a comparable distance away based on the apparent interaction between it and 5566 but that’s me reading into the data, not anything I’ve read from an authoritative source. NGC 5569 to the bottom right is estimated to be about 94 million light years away so it is not likely to be interacting with those two galaxies.

This is 24h 40m of LRGB data. For all the technical details, see astrobin.