NGC 4631 is a barred spiral galaxy in the constellation Canes Venatici. This galaxy's slightly distorted wedge shape gives it the appearance of a herring or a whale, hence its nickname. Because this nearby galaxy is seen edge-on from Earth, professional astronomers observe this galaxy to better understand the gas and stars located outside the plane of the galaxy.
Centaurus A is a galaxy in the constellation of Centaurus. It was discovered in 1826 by Scottish astronomer James Dunlop from his home in Parramatta, in New South Wales, Australia. There is considerable debate in the literature regarding the galaxy's fundamental properties such as its Hubble type and distance. NGC 5128 is one of the closest radio galaxies to Earth, so its active galactic nucleus has been extensively studied by professional astronomers. The galaxy is also the fifth-brightest in the sky, making it an ideal amateur astronomy target. It is only visible from the southern hemisphere and low northern latitudes.
NGC 4676, or the Mice Galaxies, are two spiral galaxies in the constellation Coma Berenices. About 290 million light-years distant, they have begun the process of colliding and merging. Their name refers to the long tails produced by tidal action—the relative difference between gravitational pulls on the near and far parts of each galaxy—known here as a galactic tide. It is a possibility that both galaxies, which are members of the Coma Cluster, have experienced collision, and will continue colliding until they coalesce.
NGC 4414 is an unbarred spiral galaxy about 62 million light-years away in the constellation Coma Berenices. It is a flocculent spiral galaxy, with short segments of spiral structure but without the dramatic well-defined spiral arms of a grand design spiral. Three supernovae have been observed in this galaxy: SN 1974G, SN 2013df, and SN 2021J.
NGC 3227 is an intermediate spiral galaxy that is interacting with the dwarf elliptical galaxy NGC 3226. The two galaxies are one of several examples of a spiral with a dwarf elliptical companion that are listed in the Atlas of Peculiar Galaxies. Both galaxies may be found in the constellation Leo. It is a member of the NGC 3227 Group of galaxies, which is a member of the Leo II Groups, a series of galaxies and galaxy clusters strung out from the right edge of the Virgo Supercluster.
NGC 3226 is a dwarf elliptical galaxy that is interacting with the spiral galaxy NGC 3227. The two galaxies are one of several examples of a spiral with a dwarf elliptical companion that are listed in the Atlas of Peculiar Galaxies. Both galaxies may be found in the constellation Leo. It is a member of the NGC 3227 Group of galaxies, which is a member of the Leo II Groups, a series of galaxies and galaxy clusters strung out from the right edge of the Virgo Supercluster.
NGC 4088 is an intermediate spiral galaxy in the constellation Ursa Major. The galaxy forms a physical pair with NGC 4085, which is located 11′ away.
NGC 772 is an unbarred spiral galaxy approximately 130 million light-years away in the constellation Aries.
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.
NGC 2207 and IC 2163 are a pair of colliding spiral galaxies about 80 million light-years away in the constellation Canis Major. Both galaxies were discovered by John Herschel in 1835.
NGC 4027 is a barred spiral galaxy approximately 83 million light-years away in the constellation Corvus. It is also a peculiar galaxy because one of its spiral arms goes out more than the other. This is probably due to a galactic collision in NGC 4027's past.
NGC 5253 is an irregular galaxy in the constellation Centaurus. It was discovered by William Herschel on 15 March 1787.
NGC 4618 is a distorted barred dwarf galaxy in the constellation Canes Venatici. The galaxy is formally classified as a Sm galaxy, which means that its structure vaguely resembles the structure of spiral galaxies. The galaxy is sometimes referred to as a Magellanic spiral because of its resemblance to the Magellanic clouds.
NGC 4319 is a face-on barred spiral galaxy located about 77 million light years away in the constellation Draco. The morphological classification is SB(r)ab, which indicates it is a barred spiral with an inner ring structure and moderate to tightly wound arms. It is situated in physical proximity to the galaxies NGC 4291 and NGC 4386, with X-ray emissions from the intervening gap indicating NGC 4319 and NGC 4291 may be interacting. NGC 4319 has a much higher proportion of ionized hydrogen compared to the Milky Way galaxy.
NGC 4559 is an intermediate spiral galaxy with a weak inner ring structure in the constellation Coma Berenices. Distance estimates for NGC 4559 range from about 28 million light-years to 31 million light-years, averaging about 29 million light-years.
NGC 2535 is an unbarred spiral galaxy exhibiting a weak inner ring structure around the nucleus in the constellation Cancer that is interacting with NGC 2536. The interaction has warped the disk and spiral arms of NGC 2535, producing an elongated structure, visible at ultraviolet wavelengths, that contain many bright, recently formed blue star clusters in addition to enhanced star forming regions around the galaxy center. The two galaxies are listed together in the Atlas of Peculiar Galaxies as an example of a spiral galaxy with a high surface brightness companion.
NGC 2536 is a barred spiral galaxy with a prominent inner ring structure encircling the bar in the constellation Cancer that is interacting with NGC 2535. The two galaxies are listed together in the Atlas of Peculiar Galaxies as an example of a spiral galaxy with a high surface brightness companion.
NGC 2608 is a barred spiral galaxy located 93 million light-years away in the constellation Cancer. It is 62,000 light-years across, and about 60% of the width of the Milky Way. It is considered a grand design spiral galaxy and is classified as SB(s)b, meaning that the galaxy's arms wind moderately around the prominent central bar.
NGC 1023 is a barred lenticular galaxy, a member of the NGC 1023 group of galaxies in the Local Supercluster. Distance measurements vary from 9.3 to 19.7 million parsecs (30 to 64 million light-years). The supermassive black hole at the core has a mass of (4.4±0.5)×107 M☉. The black hole was discovered by analyzing the dynamics of the galaxy.
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.
