Atlas of Peculiar Galaxies

The Atlas of Peculiar Galaxies is a catalog of peculiar galaxies produced by Halton Arp. A total of 338 galaxies are presented in the atlas, which was originally published in 1966 by the California Institute of Technology.The primary goal of the catalog was to present photographs of examples of the different kinds of peculiar structures found among nearby galaxies. Arp realized that the reason why galaxies formed into spiral or elliptical shapes was not well understood. He perceived peculiar galaxies as small "experiments" that astronomers could use to understand the physical processes that distort spiral or elliptical galaxies. With this atlas, astronomers had a sample of peculiar galaxies that they could study in more detail. The atlas does not present a complete overview of every peculiar galaxy in the sky but instead provides examples of the different phenomena as observed in nearby galaxies.
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