The Atlas of Peculiar Galaxies is a catalog of peculiar galaxies produced by Halton Arp in 1966. 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 galaxies.
Arp 87 is a pair of interacting galaxies, NGC 3808A and NGC 3808B. They are situated in the Leo constellation. NGC 3808A, the brighter, is a peculiar spiral galaxy, while NGC 3808B is an irregular galaxy.
NGC 5579 is an intermediate spiral galaxy in the northern constellation of Boötes. It was discovered on May 1, 1785) by German-British astronomer William Herschel. The galaxy is located at a distance of 179 ± 14 million light-years (54.9 ± 4.3 Mpc) from the Milky Way, and is receding with a heliocentric radial velocity of 3,608 km/s. It is entry 69 in Halton Arp's Atlas of Peculiar Galaxies.
NGC 5665 is a spiral galaxy in the northern constellation of Boötes. It was discovered on January 30, 1784 by German-British astronomer William Herschel. This galaxy is located at a distance of 53.6 ± 7.7 million light-years (16.44 ± 2.37 Mpc), and is receding with a heliocentric radial velocity of 2,237 km/s. It is cataloged in Halton Arp's Atlas of Peculiar Galaxies as object number 49.
NGC 14 is an irregular galaxy in the Pegasus constellation. It was included in Halton Arp's Atlas of Peculiar Galaxies, under the section "Galaxies with the appearance of fission," since the irregular appearance of this galaxy causes it to look like it is coming apart. It was discovered on September 18, 1786, by William Herschel.
Arp 273 is a pair of interacting galaxies, 300 million light years away in the constellation Andromeda. It was first described in the Atlas of Peculiar Galaxies, compiled by Halton Arp in 1966. The larger of the spiral galaxies, known as UGC 1810, is about five times more massive than the smaller galaxy. It has a disc that is tidally distorted into a rose-like shape by the gravitational pull of the companion galaxy below it, known as UGC 1813. The smaller galaxy shows distinct signs of active star formation at its nucleus, and "it is thought that the smaller galaxy has actually passed through the larger one."
NGC 5566 is a barred spiral galaxy in the constellation Virgo, which is approximately 66 million light years away from Earth. The galaxy is the biggest in the constellation Virgo, stretching nearly 150,000 light years in diameter. The galaxy NGC 5566 was discovered on 30 April 1786 by the German-British astronomer William Herschel. It is included in Halton Arp's Atlas of Peculiar Galaxies. It is a member of the NGC 5566 Group of galaxies, itself one of the Virgo III Groups strung out to the east of the Virgo Supercluster of galaxies.
NGC 7727 is a peculiar galaxy in the constellation Aquarius. It harbors two galactic nuclei, each containing a supermassive black hole, separated 1,600 light years apart.
Arp 7 is a spiral galaxy in the constellation Hydra. Redshift-independent measurements of its distance vary widely, from 5.9 Mpc to 83.7 Mpc. Its morphological classification is SB(rs)bc, meaning it is a barred spiral galaxy with some ring-like structure.
NGC 2857 is a spiral galaxy in the constellation Ursa Major. It was discovered on January 9, 1856, by R. J. Mitchell.
NGC 169 is a barred spiral galaxy located in the constellation Andromeda. It was discovered on September 18, 1857 by R. J. Mitchell.
NGC 7603 is a spiral Seyfert galaxy in the constellation Pisces. It is listed in the Atlas of Peculiar Galaxies. It is interacting with the smaller elliptical galaxy PGC 71041 nearby.
NGC 4647 is an intermediate spiral galaxy estimated to be around 63 million light-years away in the constellation of Virgo. It was discovered by astronomer William Herschel on March 15, 1784. NGC 4647 is listed along with Messier 60 as being part of a pair of galaxies called Arp 116; their designation in Halton Arp's Atlas of Peculiar Galaxies. The galaxy is located on the outskirts of the Virgo Cluster.
NGC 497 is a barred spiral galaxy approximately 336 million light-years away from Earth in the constellation of Cetus. It was discovered by French astronomer Édouard Stephan on November 6, 1882.
NGC 7393 is a barred spiral galaxy in the constellation Aquarius. It is estimated to about 120 million light-years from the Milky Way and about 70,000 light-years in diameter. NGC 7393 belongs to the class of spiral galaxies with separated sections in the Arp catalog. Astronomer Halton Arp divided his catalog of unusual galaxies into groups based on purely morphological criteria. NGC 7393 was discovered by astronomer William Herschel on October 5, 1785.
NGC 7829 is a lenticular galaxy in the constellation Cetus. NGC 7829 was discovered by American astronomer Francis Leavenworth in 1886. NGC 7829 forms with its neighbor NGC 7828 a pair of gravitationally interacting galaxies. The pair appears in Halton Arp's Atlas of Peculiar Galaxies as Arp 144.
NGC 5278 is a spiral galaxy in the constellation Ursa Major. It was discovered by German-British astronomer William Herschel in 1789. NGC 5278 is in gravitational interaction with the galaxy NGC 5279. This pair of galaxies appears in the Halton Arp's Atlas of Peculiar Galaxies under the symbol Arp 239. The luminosity class of NGC 5278 is II. The nucleus of this galaxy presents a burst of star formation and it is an active Seyfert 2 type galaxy. In addition, NGC 5278 is possibly a LINER galaxy, a galaxy whose nucleus presents an emission spectrum characterized by broad lines of weakly ionized atoms. NGC 5278 is also a galaxy whose core shines in the ultraviolet spectrum. It is listed in the Markarian catalog under the reference Mrk 271.
NGC 3800 is an intermediate spiral galaxy located in the constellation Leo. Its speed relative to the cosmic microwave background is 3,653 ± 24 km/s, which corresponds to a Hubble distance of 53.9 ± 3.8 Mpc. NGC 3800 was discovered by German-British astronomer William Herschel in 1784.
NGC 3799 is a barred spiral galaxy located in the constellation Leo. Its speed relative to the cosmic microwave background is 3,659 ± 24 km/s, which corresponds to a Hubble distance of 54.0 ± 3.8 Mpc. NGC 3799 was discovered by British astronomer John Herschel in 1832.
NGC 6365 is a pair of spiral galaxies in the constellation Draco. It consists of two galaxies, PGC 60174 to the south, and PGC 60171 to the north. These two galaxies are also designated respectively by the NASA/IPAC database as NGC 6365A and NGC 6365B. This pair of galaxies was discovered by German astronomer Lewis Swift in 1884.
