115 Sentences With "irregular galaxy" | Random Sentence Generator

The spiral galaxy was passing the irregular galaxy when the collision happened.

This irregular galaxy, 30 million years away in the Virgo constellation, has a bar of stars running through the middle.

While most galaxies have a spiral or elliptical structure, NGC 5408 is an irregular galaxy, meaning it sports a messy, indefinable shape.

NGC 4490, a spiral galaxy with a central bar structure made of stars, is the larger galactic neighbor of NGC 4485, an irregular galaxy with no defined shape.

To nearly everybody's surprise, as reported in January in the journal Nature, the bursts originated in a small "dwarf irregular" galaxy, one about a gigaparsec (just over 1980 billion light years) away.

It's actually a galaxy that among astronomers goes by special names: an irregular galaxy; a starburst galaxy for its off-the-charts rate of star formation; and also IC 2100, a member of a set of more than 21 galaxies called the Local Group.

DDO 216 (also known as Pegasus Dwarf Irregular Galaxy, PGC 71538 or UGC 12613) is a dwarf irregular galaxy located in the constellation Pegasus.

The Sculptor Dwarf Irregular Galaxy (SDIG) is an irregular galaxy in the constellation Sculptor. It is a member of the NGC 7793 subgroup of the Sculptor Group. The galaxy was discovered in 1976.

NGC 1427A, an example of an irregular galaxy. It is an Irr-I category galaxy about 52 Mly distant. An irregular galaxy is a galaxy that does not have a distinct regular shape, unlike a spiral or an elliptical galaxy.Butz, Stephen D. (2002).

The Pegasus Dwarf Irregular Galaxy (also known as Peg DIG or the Pegasus Dwarf) is a dwarf irregular galaxy in the direction of the constellation Pegasus. It was discovered by A. G. Wilson in the 1950s. The Pegasus Dwarf is a companion of the Andromeda Galaxy in the Local Group.

NGC 5408 is an irregular galaxy in the constellation Centaurus. It was discovered by John Herschel on June 5, 1834.

NGC 87 is a diffuse, highly disorganized barred irregular galaxy, part of Robert's Quartet, a group of four interacting galaxies.

NGC 6789 is an irregular galaxy in the constellation Draco. It was discovered by Lewis Swift on Aug 30, 1883.

NGC 3741 is an irregular galaxy in the constellation Ursa Major. It was discovered by John Herschel on March 19, 1828.

NGC 5829 is a spiral galaxy in the constellation Boötes that is interacting with the irregular galaxy IC 4526. Together, the two form the galaxy pair Arp 42.

NGC 4214 is a dwarf barred irregular galaxy located around 10 million light- years away in the constellation Canes Venatici. NGC 4214 is a member of the M94 Group.

DDO 169 (also known as PGC 46127 or UGC 8331) is a dwarf irregular galaxy in the constellation Canes Venatici. It is one of the members of the M51 Group.

DDO 190 (also known as UGC 9240) is a dwarf irregular galaxy which is located in the constellation of Boötes. It is a member of the M94 Group as well.

Messier 49 is gravitationally interacting with the dwarf irregular galaxy UGC 7636. The dwarf shows a trail of debris spanning roughly 1 × 5 arcminutes, which corresponds to a physical dimension of .

DDO 70 (also known as Sextans B, PGC 28913 or UGC 5373) is an irregular galaxy which is in the constellation of Sextans. It is located 4.44 million light years away from Earth.

NGC 5253 is an irregular galaxy in the constellation Centaurus. It was discovered by William Herschel on 15 March 1787.The scientific papers of Sir William Herschel by J. L. E. Dreyer. Royal Astronomical Society London 1912.

DDO 69 (also known as Leo A, Leo III, PGC 28868 or UGC 5364) is an irregular galaxy which is located in the constellation of Leo. It is a small satellite galaxy of our galaxy, the Milky Way.

DDO 210 (also known as Aquarius Dwarf or PGC 65367) is a dwarf irregular galaxy in the constellation of Aquarius. It is a member of the Local Group and lies 3.2 ± 0.2 million light years from our Milky Way.

NGC 7714 appears to be a highly distorted spiral, possibly a barred spiral galaxy. NGC 7715 is of uncertain type, probably an edge-on spiral or an irregular galaxy. Supernova 1999dn was observed in NGC 7714 on September 19, 1999.

NGC 1427A, an irregular galaxy lies also near the center. Fornax cluster is a place where are ultracompact dwarf galaxies discovered first, in 2003. Almost all of them are surrounding the NGC 1399, as its central galaxy of the cluster.

UGC 2140 is an irregular galaxy in the constellation Aries. It was thought to be a compact group of galaxies, catalogued as HCG 18, but in 1999 the object was found to be a single galaxy with multiple star-forming regions.

2MASX J16270254+4328340 galaxy has merged with another galaxy leaving a fine mist, made of millions of stars, spewing from it in long trails. Galactic cannibalism refers to the process in which a large galaxy, through tidal gravitational interactions with a companion, merges with that companion; that results in a larger, often irregular galaxy. The most common result of the gravitational merger between two or more galaxies is an irregular galaxy, but elliptical galaxies may also result. It has been suggested that galactic cannibalism is currently occurring between the Milky Way and the Large and Small Magellanic Clouds.

This galaxy is presumed to be the primary location of the 2004-2009 science fiction television series Stargate Atlantis. While it's mentioned the show takes place in "the Pegasus galaxy" it has not explicitly stated if it is the Irregular or Spheroidal. However, when the Pegasus galaxy has been seen from the Midway station an irregular galaxy is shown. Also, in the discussion regarding the new McKay–Carter Intergalactic Gate Bridge, General Hank Landry states that the distance between the Pegasus and Milky Way galaxies is "three million light-years", suggesting that the series takes place in the Pegasus Dwarf Irregular Galaxy.

It is a Seyfert galaxy, the only one in Fornax Cluster. NGC 1427A is an irregular galaxy in the constellation Eridanus. Its distance modulus has been estimated using the globular cluster luminosity function to be 31.01 ± 0.21 which is about 52 Mly.

The NGC 1569 is a dwarf irregular galaxy in Camelopardalis. The galaxy is relatively nearby. Consequently, the Hubble Space Telescope can easily resolve the stars within the galaxy. The distance to the galaxy was previously believed to be only 2.4 Mpc (7.8 Mly).

DDO 75 (also known as Sextans A, PGC 29653 or UGCA 205) is an irregular galaxy located in the constellation Sextans, same as its neighbour DDO 70 (Sextans B). When it is observed from Earth, it appears as a square in shape.

Messier 90 is rich in globular clusters, with around 1,000 of them and has a satellite galaxy (IC 3583), which is an irregular galaxy. Both galaxies were thought to be interacting; however, it is now thought they are too far away to be interacting at all.

NGC 1487 is an irregular galaxy in the constellation Eridanus. It was discovered by James Dunlop on Oct 29, 1826. It is thought to be the remnant of two galaxies, which are the components NGC 1487E and NGC 1487W, that collided about 500 million years ago.

The Phoenix Dwarf is a dwarf irregular galaxy discovered in 1976 by Hans-Emil Schuster and Richard Martin West and mistaken for a globular cluster. It is currently 1.44 Mly away from Earth. Its name comes from the fact that it is part of the Phoenix constellation.

DDO 155 (also known as GR 8, PGC 44491 or UGC 8091) is a dwarf irregular galaxy located approximately 7.9 million light years away from Earth in the constellation of Virgo. People give a nickname to this galaxy, called 'Imprint of a Foot' because of its shape.

GR 8 (also known as UGC 8091) is a gas-rich dwarf irregular galaxy. In 1995, Tolstoy et al. estimated its distance (with the Hipparcos correction of 1997 applied) to be approximately from Earth. There is still open question regarding if it is a member of the Local Group.

NGC 4630 is an irregular galaxy located about 54 million light-years away in the constellation of Virgo. NGC 4630 was discovered by astronomer William Herschel on February 2, 1786. NGC 4630 is part of the Virgo II Groups which form a southern extension of the Virgo Cluster.

KKH 060 is an irregular galaxy and a low surface brightness galaxy located in the direction of the constellation Leo at a distance of 4.89 million light years from Earth. The galaxy is close to the Local Group, but is not considered to be a member of it.

DDO 8 (also known as IC 1613, PGC 3844, UGC 668 or Caldwell 51) is a dwarf irregular galaxy in the constellation Cetus, near the border of Pisces. It was discovered in 1906 by a German astronomer Max Wolf. It is a member of the Local Group as well.

The Wolf–Lundmark–Melotte (WLM) is a barred irregular galaxy discovered in 1909 by Max Wolf, located on the outer edges of the Local Group. The discovery of the nature of the galaxy was accredited to Knut Lundmark and Philibert Jacques Melotte in 1926. It is in the constellation Cetus.

As a consequence of the gravitational interaction with the Whirlpool Galaxy, NGC 5195 is highly distorted. Classification of its morphology is difficult, as it is sometimes identified as a lenticular galaxy or as an amorphous or irregular galaxy. It has been described as falling outside the standard morphological classification system.

UGC 9405 (also known as PGC 52142) is a faint dwarf irregular galaxy situated in the constellation of Ursa Major. It is the member of the M101 Group, a group containing the several galaxies orbiting the largest, Pinwheel Galaxy (M101). UGC 9405 is also the faintest member of M101 Group, with apparent magnitude of 17.

NGC 1427A is an irregular galaxy in the constellation Eridanus. Its distance modulus has been estimated using the globular cluster luminosity function to be 31.01 ± 0.21 which is about 52 Mly. It is the brightest dwarf irregular member of the Fornax cluster and is in the foreground of the cluster's central galaxy NGC 1399.

The Spiderweb Galaxy (PGC 2826829, MRC 1138-262) is an irregular galaxy with a redshift of 2.156, which is 10.6 billion light years away. It has been recently imaged by the Hubble Space Telescope. It is formed from dozens of smaller galaxies that were seen in the process of merging through mutual gravitational attraction.

M82 was previously believed to be an irregular galaxy. In 2005, however, two symmetric spiral arms were discovered in near-infrared (NIR) images of M82. The arms were detected by subtracting an axisymmetric exponential disk from the NIR images. Even though the arms were detected in NIR images, they are bluer than the disk.

Arp 87 (also known as NGC 3808) is a pair of two 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. The two galaxies were discovered on 10 April 1785 by William Herschel.

In this sense, it was akin to a nova explosion, although the magnitude of the explosion was a thousand times greater. In 2007 Lars Bildsten et al. had predicted this category of explosion would occur in AM Canum Venaticorum star binary systems. NGC 1821 is an irregular galaxy categorized as type IB(s)m.

The Antlia Dwarf is a dwarf spheroidal/irregular galaxy. It lies about 1.3 Mpc (4.3 million light-years) from Earth in the constellation Antlia. It is the fourth and faintest member of the nearby Antlia-Sextans Group of galaxies. The galaxy contains stars of all ages, contains significant amounts of gas, and has experienced recent star formation.

NGC 300 and the irregular galaxy NGC 55 have traditionally been identified as members of the Sculptor Group, a nearby group of galaxies in the constellation of the same name. However, recent distance measurements indicate that these two galaxies actually lie in the foreground. It is likely that NGC 300 and NGC 55 form a gravitationally bound pair.

'NGC 1156 is a dwarf irregular galaxy in the Aries constellation of the type '. It is considered a Magellanic-type irregular. The galaxy has a larger than average core, and contains zones of contra-rotating gas. The counter-rotation is thought to be the result of tidal interactions with another gas rich galaxy some time in the past.

NGC 5308 is an edge-on lenticular galaxy in the constellation of Ursa Major. It was discovered on 19 March 1790 by William Herschel. It was described by John Louis Emil Dreyer as "bright, pretty large" when he compiled the New General Catalogue. A small, irregular galaxy near NGC 5308 has been given the designation LEDA 2802348.

The Canis Major Overdensity (CMa Overdensity) or Canis Major Dwarf Galaxy (CMa Dwarf) is a disputed dwarf irregular galaxy in the Local Group, located in the same part of the sky as the constellation Canis Major. The supposed small galaxy contains a relatively high percentage of red giants and is thought to contain an estimated one billion stars in all. The Canis Major Dwarf Galaxy is classified as an irregular galaxy and is now thought to be the closest neighboring galaxy to the Earth's location in the Milky Way, being located about away from the Solar System and from the Galactic Center. It has a roughly elliptical shape and is thought to contain as many stars as the Sagittarius Dwarf Elliptical Galaxy, the previous contender for closest galaxy to our location in the Milky Way.

Haro 11 (H11) is a small galaxy at a distance of (redshift z=0.020598). It is situated in the southern constellation of Sculptor. Visually, it appears to be an irregular galaxy, as the ESO image to the right shows. H11 is named after Guillermo Haro, a Mexican astronomer who first included it in a study published in 1956 about blue galaxies.

The galaxy was identified as a blue compact dwarf, a type of small irregular galaxy undergoing a strong burst of star formation. The spectrum of PHL 293B is unusual both for its low metallicity and for broad hydrogen emission lines with P Cygni profiles. The emission lines are interpreted as being from a single luminous blue variable star within the galaxy.

NGC 3109 is a small barred Magellanic type spiral or irregular galaxy around 4.34 Mly away in the direction of the constellation of Hydra. NGC 3109 is believed to be tidally interacting with the dwarf elliptical galaxy Antlia Dwarf.Grebel, Gallagher, Harbeck, p.7 It was discovered by John Herschel on March 24, 1835 while he was in what is now South Africa.

It was based on the infrared Tully–Fisher relation. As of 2011, the distance to Dwingeloo 1 is thought to be approximately 3 Mpc, based on its likely membership in the IC 342/Maffei group. Dwingeloo 1 has two smaller satellite galaxies. The first one, Dwingeloo 2, is an irregular galaxy, and the second, MB 3, is likely a dwarf spheroidal galaxy.

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 separating apart. (webpage includes PDF link) It was discovered on September the 18th 1786 by William Herschel.

IC 4710 is galaxy in southern constellation of Pavo, roughly 34 million light- years away. Discovered on August 18, 1900 by astronomer DeLisle Stewart, this galaxy is composed of bright stars, with bright pockets — marking bursts of new star formation — scattered around its edges. It has a diameter of 36,000 light-years. IC 4710 is classified as dwarf irregular galaxy.

IC 4662, also known as ESO 102-14 is irregular galaxy located in Constellation Pavo 7.96 million lightyears away. It was discovered by Robert Thorbun Ayton Innes in 1901. It has a diameter of 7000 lightyears and an angular size of 3.2' x 1.9'. IC 4662 is part of a Hubble study of starbursts in nearby, small, or dwarf, galaxies.

A barred irregular galaxy is an irregular version of a barred spiral galaxy. Examples include the Large Magellanic Cloud and NGC 6822.Norbert Przybilla, Quantitative Spectroscopy of Supergiants, Munich, 2002 Some barred irregular galaxies (like the Large Magellanic Cloud) may be dwarf spiral galaxies, which have been distorted into an irregular shape by tidal interactions with a more massive neighbor.

NGC 1592 is an irregular galaxy in the constellation Eridanus. It is about 20,000 light years across. It has not been studied in detail, as it is at 27 degrees south, making it not visible below 63 degrees north in a flat area, and about 50 degrees north in a hilly area. It was discovered in 1835 by John Herschel.

However, due to its highly irregular shape, it may also be classified as a dwarf irregular galaxy. In fact, since dwarf galaxies are less massive and have lower gravitational potentials, gases and other material for star formation can move within them much faster, causing the galaxy to become a specific type of starburst galaxy, called a blue compact dwarf galaxy.

NGC 5238 is an irregular galaxy in the constellation Canes Venatici. Located at a comoving distance of 4.51 Mpc, it is 64.4 arcseconds in diameter. It has sometimes been classified as a blue compact dwarf galaxy. Although some authors have hypothesized it to be a member of the M101 Group of galaxies, it is currently believed to be an isolated galaxy.

NGC 6745 (also known as UGC 11391) is an irregular galaxy about 206 million light-years (63.5 mega-parsecs) away in the constellation Lyra. It is actually a trio of galaxies in the process of colliding. The three galaxies have been colliding for hundreds of millions of years. After passing through the larger galaxy (NGC 6745A), the smaller one (NGC 6745B) is now moving away.

Using its Hess diagram, they found that its evolutionary history may be similar to that of the Pegasus Dwarf Irregular Galaxy. Both galaxies are classified as Ir V in the DDO system. Also in 1999, Antonello et al. found five cepheids of Population II in IC 1613, giving self-evident support for the existence of a very old stellar population component of IC 1613.

UGC 4879, which is also known as VV 124, is the most isolated dwarf galaxy in the periphery of the Local Group. It is an irregular galaxy at a distance of 1.38 Mpc. Low-resolution spectroscopy yielded inconsistent radial velocities for different components of the galaxy, hinting at the presence of a stellar disk. There is also evidence of this galaxy containing dark matter.

Holmberg IX is a dwarf irregular galaxy and a satellite galaxy of M81. The galaxy is named after Erik Holmberg who first described it. Based on the observed age distribution of stars it contains it is thought to have formed within the last 200 Myr making it the youngest nearby galaxy. It is also home to one of two newly discovered yellow supergiant eclipsing binary systems.

NGC 4163, also known as NGC 4167 is a dwarf irregular galaxy in constellation Canes Venatici, about 9.65 million light-years away. It was discovered by William Herschel on April 28, 1785 as NGC 4163. John Herschel discovered it again on March 11, 1831 as NGC 4167. It has a size on night sky 1.9' x 1.6' and it, with distance, gives diameter of 4000 light-years.

IC 883 (also known as Arp 193, IRAS 13183+3423, PGC 46560 and UGC 8387) is an irregular galaxy that is about 321 million light years away from Earth. It is located in the constellation Canes Venatici. Its largest radius is 1.4 (131 thousand light years), and smallest 0.7 angular minutes (65 thousand light years). It was discovered by Rudolf Ferdinand Spitaler on May 1 1891.

In 1979, the galaxy was classified as a barred spiral galaxy. Soon after, in 1984, the galaxy was included in a study of blue compact dwarf galaxies, incompatible with the classification of a barred spiral. However, the barred spiral classification was considered the correct classification for years. It was not until the mid 1990s that the galaxy was first recognized as a dwarf irregular galaxy.

The Irregular Galaxy NGC 1427A. Credit ESO NGC 1427A is over 20,000 light-years long and similar to the Large Magellanic Cloud. The resulting pressure is giving the galaxy its arrowhead outline and triggering the beautiful but violent episodes of star formation. Under the influence of galactic tides, NGC 1427A is travelling into the center of the Fornax cluster with a velocity of approximately 600 km per second.

NGC 3239 is an irregular galaxy in the constellation of Leo. It is the host of SN 2012A, the first supernova of 2012. The galaxy, which was discovered in 1784 by William Herschel, is part of the New Galactic Catalogue, and with an apparent magnitude of 13.5, is not visible to the naked eye. It has been shown to have many HII regions, while also having some star formation regions.

The constellation does not lie on the galactic plane of the Milky Way, and there are no prominent star clusters. NGC 625 is a dwarf irregular galaxy of apparent magnitude 11.0 and lying some 12.7 million light years distant. Only 24000 light years in diameter, it is an outlying member of the Sculptor Group. NGC 625 is thought to have been involved in a collision and is experiencing a burst of active star formation. NGC 37 is a lenticular galaxy of apparent magnitude 14.66. It is approximately 42 kiloparsecs (137,000 light-years) in diameter and about 12.9 billion years old. Robert's Quartet (composed of the irregular galaxy NGC 87, and three spiral galaxies NGC 88, NGC 89 and NGC 92) is a group of four galaxies located around 160 million light-years away which are in the process of colliding and merging. They are within a circle of radius of 1.6 arcmin, corresponding to about 75,000 light-years.

DDO 190 (or UGC 9240) is a dwarf irregular galaxy in the vicinity of the Milky Way, as it is relatively small and lacks clear structure. It is away from Earth and lies out of the Local Group, determined by the tip of the red giant branch method. The outskirts of the galaxy are harbouring older (reddish) stars, while the centre is crowded with younger (bluish) stars. Heated gas is observed at several places.

SDSS J1229+1122 (SDSS J122952.66+112227.8) is a blue supergiant O-type star in the tail of dwarf irregular galaxy IC 3418. It illuminates a nebula clump of gas, and was discovered from the spectrum of the illumination source. The clump of gas resides in a tail caused by ram pressure stripping of gas from the galaxy by the galaxy cluster. It was determined to be a blue supergiant through analysis of its spectrum.

IC 5152 is an irregular galaxy 5.8 million light-years from Earth in the constellation Indus. It was discovered by DeLisle Stewart in 1908. It is an open question as to whether it is an outlying member of the Local Group. It is one of the easiest galaxies to resolve into stars, but there is a bright (magnitude 7.7) foreground star (HD 209142) right in front of it that makes deep observations difficult.

IC 3583 is an irregular galaxy some 30 million light-years away in the constellation of Virgo. It was discovered by Isaac Roberts on April 29, 1892. It may seem to have no discernable structure, but IC 3583 has been found to have a bar of stars running through its centre. These structures are common throughout the Universe, and are found within the majority of spiral, many irregular, and some lenticular galaxies.

NGC 6822 (also known as Barnard's Galaxy, IC 4895, or Caldwell 57) is a barred irregular galaxy approximately 1.6 million light-years away in the constellation Sagittarius. Part of the Local Group of galaxies, it was discovered by E. E. Barnard in 1884 (hence its name), with a six-inch refractor telescope. It is one of the closer galaxies to the Milky Way. It is similar in structure and composition to the Small Magellanic Cloud.

NGC 3109 is the largest and dominant member of this group, with a diameter of 25,000 light-years, one- fifth to one-quarter the diameter of the Milky Way. It was the first discovered member of the group, discovered in 1835. It is also second closest to Earth, at a distance of 4.338 million light-years away. It was thought to be an irregular galaxy, but is now theorized to possibly be a barred spiral.

NGC 4707 is an irregular galaxy in the constellation of Canes Venatici. It was discovered by John Herschel on 5 June 1834, and was described by John Louis Emil Dreyer, the compiler of the New General Catalogue, as a "small, stellar" galaxy. NGC 4707 has a morphological type of Sm or Im, meaning that it is mostly irregular or has very weak spiral arms. The galaxy was imaged by the Hubble Space Telescope in 2016.

The Magellanic Cloud galaxies were once classified as irregular galaxies. The Large Magellanic Cloud has since been re-classified as type SBm Corso, G. and Buscombe, W. The Observatory, 90, 229 - 233 (1970) On the spiral structure of the Large Magellanic Cloud a type of barred spiral galaxy, the barred Magellanic spiral type. The Small Magellanic Cloud remains classified as an irregular galaxy of type Im under current Galaxy morphological classification, although it does contain a bar structure.

Leo A (also known as Leo III) is an irregular galaxy that is part of the Local Group. It lies 2.6 million light-years from Earth, and was discovered by Fritz Zwicky in 1942. The estimated mass of this galaxy is solar masses, with at least 80% consisting of an unknown dark matter. It is one of the most isolated galaxies in the Local Group and shows no indications of an interaction or merger for several billion years.

NGC 3109 is classified as a Magellanic type irregular galaxy, but it may in fact be a small spiral galaxy. If it is a spiral galaxy, it would be the smallest in the Local Group. NGC 3109 has a mass of about 2.3×109 times the mass of the Sun, of which 20% is in the form of neutral hydrogen. It is oriented edge-on from our point of view, and may contain a disk and a halo.

NGC 7250 is an irregular galaxy located in the Lacerta constellation. It is a blue-colored galaxy with bright bursts of star formation: its star forming rate is more than an order of magnitude greater than that of the Milky Way. In 2013, a type Ia supernova was detected within the galaxy, and was designated SN 2013dy. It was detected about 2.4 hours after the explosion, making it the earliest known detection of a supernova at the time.

The Sagittarius Dwarf Irregular Galaxy (SagDIG) is a dwarf galaxy in the constellation of Sagittarius. (SagDIG should not be confused with the Sagittarius Dwarf Elliptical Galaxy, SagDEG, a satellite galaxy of the Milky Way discovered decades later in the same constellation.) It lies about 3.4 million light-years away. It was discovered by Cesarsky et al. on a photographic plate taken for the ESO (B) Atlas on 13 June 1977 using the ESO 1 meter Schmidt telescope.

NGC 1140 is an irregular galaxy in the southern constellation of Eridanus. Estimates made using the Tully–Fisher method put the galaxy at about 59 million light years (18 megaparsecs). It was discovered on 22 November 1786 by William Herschel, and was described as "pretty bright, small, round, stellar" by John Louis Emil Dreyer, the compiler of the New General Catalogue. NGC 1140 is a starburst galaxy, meaning it is forming stars at a very fast rate.

The Antlia Dwarf is located about away, in the constellation Antlia. Its distance from the barycenter of the Local Group is about 1.7 Mpc. At this distance, it is situated well outside the Local Group and is a member of a separate group of dwarf galaxies called Antlia-Sextans Group. The Antlia Dwarf is separated from the small spiral/irregular galaxy NGC 3109 by only 1.18 degrees on the sky, which corresponds to a physical separation of to depending on their radial separation.

Sextans A (also known as UGCA 205) is a tiny dwarf irregular galaxy. It spans about 5000 light-years across, and is located at 4.3 million light-years away, in the outskirts of the Local Group of galaxies, which includes the Milky Way galaxy, and to which Sextans A may or may not belong. Sextans A has a peculiar square shape. Massive short-lived stars exploded in supernovae that caused more star formation, triggering yet more supernovae, ultimately resulting in an expanding shell.

Cassiopeia A is a supernova remnant and the brightest extrasolar radio source in the sky at frequencies above 1 GHz. Fourteen star systems have been found to have exoplanets, one of which—HR 8832—is thought to host seven planets. A rich section of the Milky Way runs through Cassiopeia, containing a number of open clusters, young luminous galactic disc stars, and nebulae. IC 10 is an irregular galaxy that is the closest known starburst galaxy and the only one in the Local Group of galaxies.

NGC 5264, also known as DDO 242, is an irregular galaxy in the constellation Hydra. It is part of the M83 subgroup of the Centaurus A/M83 Group, located some 15 million light years (4.5 megaparsecs) away. The galaxy was discovered on 30 March 1835 by John Herschel, and it was described as "very faint, pretty large, round, very little brighter middle" by John Louis Emil Dreyer, the compiler of the New General Catalogue. NGC 5264 was imaged by the Hubble Space Telescope in 2016.

Phoenix Dwarf Galaxy is a dwarf irregular galaxy, featuring younger stars in its inner regions and older ones at its outskirts. There are many dwarf galaxies in the Local Group; these small galaxies frequently orbit larger galaxies, such as the Milky Way, the Andromeda Galaxy and the Triangulum Galaxy. A 2007 paper has suggested that many dwarf galaxies were created by galactic tides during the early evolutions of the Milky Way and Andromeda. Tidal dwarf galaxies are produced when galaxies collide and their gravitational masses interact.

The constellation also contains the Sculptor Dwarf, a dwarf galaxy which is a member of the Local Group, as well as the Sculptor Group, the group of galaxies closest to the Local Group. The Sculptor Galaxy (NGC 253), a barred spiral galaxy and the largest member of the group, lies near the border between Sculptor and Cetus. Another prominent member of the group is the irregular galaxy NGC 55. One unique galaxy in Sculptor is the Cartwheel Galaxy, at a distance of 500 million light-years.

The dwarf irregular galaxy UGCA 92 is often assumed to be a companion of NGC 1569; however, its relationship to the starburst the latter is experiencing is unclear, with some authors suggesting UGCA 92 has not started it and others suggesting it has interacted with NGC 1569, being connected with it by a tidal tail and several filaments of neutral hydrogen; however, it is still unclear if those structures are associated with them or actually within the Milky Way, being unrelated with those two galaxies.

IC 10 is an irregular galaxy in the constellation Cassiopeia. It was discovered by Lewis Swift in 1887 and in 1935 Nicholas Mayall became the first to suggest that the object is extragalactic. Edwin Hubble suspected it might belong to the Local Group of galaxies, but its status remained uncertain for decades. The radial velocity of IC 10 was measured in 1962, and it was found to be approaching the Milky Way at approximately 350 km/s, strengthening the evidence for its membership in the Local Group.

Susan Kayser is an American astronomer. She was the first woman to receive a PhD in astrophysics from the California Institute of Technology, which attracted some media attention at the time. Her thesis research included the most thorough study of the irregular galaxy NGC 6822 until 2002. She spent her career with NASA working on the Helios and International Cometary Explorer (later called the International Sun-Earth Explorer-3) spacecraft radio astronomy experiments and with the National Science Foundation working on the Gemini Observatory.

IC 10 is an irregular galaxy that is the closest known starburst galaxy and the only one in the Local Group of galaxies. Cassiopeia also contains part of the closest galaxy group to our Local Group, the IC 342/Maffei Group. The galaxies Maffei 1 and Maffei 2 are located just to the south of the Heart and Soul Nebula. As a result of this location in the Zone of Avoidance, both are surprisingly faint despite both being within 10 million light-years away (Maffei 2 is below the range of most amateur telescopes).

It has played an important role in the calibration of the Cepheid variable period-luminosity relation for estimating distances. Other than the Magellanic Clouds, it is the only Local Group dwarf irregular galaxy where RR Lyrae-type variables have been observed; this factor, along with an unusually low abundance of interstellar dust both within IC 1613 and along the line of sight enable especially accurate distance estimates., In 1999, Cole et al. used the Hubble Space Telescope to find that the dominant population of this galaxy has an age of ~7 Gyr.

Dwingeloo 2 is a small irregular galaxy discovered in 1996 and located about 10 million light-years away from the Earth. Its discovery was a result of the Dwingeloo Obscured Galaxy Survey (DOGS) of the Zone of Avoidance using the Dwingeloo Radio Observatory. Dwingeloo 2 is a companion galaxy of Dwingeloo 1. Dwingeloo 2 was first detected at radio wavelengths from the 21 cm emission line of neutral atomic hydrogen (known to astronomers as HI) in the course of follow-up observations after the discovery of Dwingeloo 1.

The red dust that has been inside the center of the galaxy has been mostly thrown out due to the collision. During the collision, gas coming from NGC 2936 triggered star formation. PGC 1237172, an unrelated bluish irregular galaxy or edge-on spiral galaxy, is located just off to the side of NGC 2936. It is located 230 million light years away, making it closer to the Earth than the NGC 2936 collision, which it happens to be located next to two unrelated stars from the Milky Way.

DDO 169 (also known as UGC 8331) is an irregular galaxy located in the constellation Canes Venatici. It is a member of the M51 Group of galaxies and measures approximately 5 × 1.5 kiloparsecs (16,000 × 5,000 lightyears). The galaxy's large-scale structure is very unorganized and it has two clusters of stars in its outer portions in addition to the cluster in the center. These clusters make it practically impossible to determine the galaxy's rotation curve and contributes to a large variation in distance figures that are derived with different methods.

Although star formation is taking place in the dusty outer ring, NGC 2775 does not display any current starburst activity, and the galactic nucleus is virtually free of any star formation whatsoever. The galaxy has a hydrogen tail feature indicates a past interaction with a faint companion. A satellite galaxy appears to have orbited NGC 2775 multiple times, losing mass as it does so and creating faint, shell-like structures. Nearby irregular galaxy NGC 2777 displays a tidal tail of hydrogen gas that points back to NGC 2775, suggesting the two may be linked.

The Large Magellanic Cloud (LMC) is a satellite galaxy of the Milky Way. At a distance of around 50 kiloparsecs (≈163,000 light-years), the LMC is the second- or third-closest galaxy to the Milky Way, after the Sagittarius Dwarf Spheroidal (~16 kpc) and the possible dwarf irregular galaxy known as the Canis Major Overdensity. Based on readily visible stars and a mass of approximately 10 billion solar masses, the diameter of the LMC is about , making it roughly one one-hundredth as massive as the Milky Way."Magellanic Cloud".

NGC 2363 as seen by the Hubble Space Telescope. The luminous blue variable star NGC 2363-V1 is the isolated bright star above and left of center. (Credit NASA) In 1996, Robert was credited, along with two other astrophysicists, for the discovery of a new luminous blue variable star called NGC 2363-V1, which is located in the star-forming region NGC 2363, at the far southwestern part of the irregular galaxy called NGC 2366 in the Camelopardalis constellation, in the northern celestial hemisphere. It is almost 11 million light years away from the Earth's galaxy.

Sextans B (also known as UGC 5373 and DDO 70) is an irregular galaxy that may be part of the Local Group, or lie just beyond it. Sextans B is 4.44 million light-years away from Earth and thus is one of the most distant members of the Local Group, if it is indeed a member. It forms a pair with its neighbouring galaxy Sextans A. It is a type Ir IV-V galaxy according to the galaxy morphological classification scheme. Sextans B may also be gravitationally associated with the galaxies NGC 3109 and the Antlia Dwarf.

The irregular galaxy NGC 55, shot by the 3.6 meter telescope at ESO's La Silla Observatory. The Webb Society Deep-Sky Observer's Handbook writes the following about NGC 55: "Nearly edge-on and appears asymmetrical with some signs of dust near the bulge, which is diffuse, broad and somewhat elongated with the south edge sharp; southeast of the bulge it is strongly curved and lined with 4 or 5 faint knots; north edge of the curve is sharp." Burnham calls it "one of the outstanding galaxies of the southern heavens", somewhat resembling a smaller version of the Large Magellanic Cloud.

NGC 4244, also known as Caldwell 26, is an edge-on loose spiral galaxy in the constellation Canes Venatici, and is part of the M94 Group or Canes Venatici I Group, a galaxy group relatively close to the Local Group containing the Milky Way.. It is located near the yellow naked-eye star, Beta Canum Venaticorum, but also near the barred spiral galaxy NGC 4151 and irregular galaxy NGC 4214. At +10.2v or 10.7B magnitude, NGC 4244 lies approximately 4.1 megaparsecs (14 million light years) away. A nuclear star cluster and halo is located near the centre of this galaxy.

The Aquarius Dwarf is a dwarf irregular galaxy, first catalogued in 1959 by the DDO survey. It is located within the boundaries of the constellation of Aquarius. It is a member of the Local Group of galaxies, albeit an extremely isolated one; it is one of only a few known Local Group members for which a past close approach to the Milky Way or Andromeda Galaxy can be ruled out, based on its current location and velocity. Local Group membership was firmly established only in 1999, with the derivation of a distance based on the tip of the red-giant branch method.

Starburst in NGC 1569 a Dwarf Irregular Galaxy (NASA photo). A starburst is an astrophysical process that involves star formation occurring at a rate that is large compared to the rate that is typically observed. This starburst activity will consume the available interstellar gas supply over a timespan that is much shorter than the lifetime of the galaxy. For example, the nebula NGC 6334 has a star formation rate estimated to be 3600 Solar Masses per million years compared the star formation rate of the entire Milky Way of about seven million solar masses per million years.

Two satellite galaxies have been detected; UGC 1453, an irregular galaxy which lies to the south, and NGC 765A, which was first detected in HI towards the north-east and has a faint visual counterpart. UGC 1453 is located 14.8 arcminutes from NGC 765, which corresponds to a projected distance of 310 kpc, and NGC 765A lies 16.5 arcminutes away, at a projected distance of 338 kpc. NGC 765 is a member of the galaxy group known as LGG 41. Other members of the group include NGC 776, IC 187, IC 188, UGC 1451, and UGC 1479.

NGC 2363-V1 is a luminous blue variable star in the star-forming region NGC 2363, at the far southwestern part of the irregular galaxy NGC 2366 in the constellation Camelopardalis, near the North Celestial Pole approaching 11 million light years away from our galaxy. It was discovered in 1996 by Laurent Drissen, Jean-René Roy, and Carmelle Robert while examining images taken by the Hubble Space Telescope Wide Field Planetary Camera 2. NGC 2363-V1 is one of the most luminous stars known. It has been undergoing an increase in temperature and luminosity for the last 20 years, after a dramatic increase in its rate of mass loss.

It is located from the Solar System and around from the barycentre of the Local Group—the second most remote of all member galaxies after the Sagittarius Dwarf Irregular Galaxy. The barred spiral galaxy NGC 7408 is located 3 degrees northwest of Delta Tucanae, and was initially mistaken for a planetary nebula. In 1998, part of the constellation was the subject of a two- week observation program by the Hubble Space Telescope, which resulted in the Hubble Deep Field South. The potential area to be covered needed to be at the poles of the telescope's orbit for continuous observing, with the final choice resting upon the discovery of a quasar, QSO J2233-606, in the field.

Andromeda IV (And IV) is an isolated irregular dwarf galaxy. The moderate surface brightness, a very blue color, low current star formation rate and low metallicity are consistent with it being a small (background) dwarf irregular galaxy, perhaps similar to Local Group dwarfs such as IC 1613 and Sextans A. Arguments based on the observed radial velocity and the tentative detection of the RGB tip suggest that it lies well outside the confines of the Local Group. Further study using the Hubble Space Telescope has shown it to be a solitary irregular dwarf galaxy. The galaxy is between 22 and 24 million light years from Earth, and so is not close to the Andromeda Galaxy at all.

The Small Magellanic Cloud (SMC), or Nubecula Minor, is a dwarf galaxy near the Milky Way. Classified as a dwarf irregular galaxy, the SMC has a diameter of about 7,000 light-years, contains several hundred million stars, and has a total mass of approximately 7 billion solar masses.NASA ADS - The total mass and dark halo properties of the Small Magellanic Cloud The SMC contains a central bar structure, and astronomers speculate that it was once a barred spiral galaxy that was disrupted by the Milky Way to become somewhat irregular. At a distance of about 200,000 light-years, the SMC is among the nearest intergalactic neighbors of the Milky Way and is one of the most distant objects visible to the naked eye.

The Tucana Dwarf is located in the constellation Tucana. It is about away, on the opposite side of the Milky Way galaxy to most of the other Local Group galaxies and is therefore important for understanding the kinematics and formation history of the Local Group, as well as the role of environment in determining how dwarf galaxies evolve. It is isolated from other galaxies, and located near the edge of the Local Group, around from the barycentre of the Local Group—the second most remote of all member galaxies after the Sagittarius Dwarf Irregular Galaxy. The Tucana Dwarf galaxy is one of only two dwarf spheroidal galaxies in the Local Group not located near the Milky Way or the Andromeda Galaxy.

Astronomers theorize that a collision with a smaller companion galaxy near the core of the main galaxy could have led to the unusual spiral structure. NGC 5253, a peculiar irregular galaxy, is located near the border with Hydra and M83, with which it likely had a close gravitational interaction 1–2 billion years ago. This may have sparked the galaxy's high rate of star formation, which continues today and contributes to its high surface brightness. NGC 5253 includes a large nebula and at least 12 large star clusters. In the eyepiece, it is a small galaxy of magnitude 10 with dimensions of 5 arcminutes by 2 arcminutes and a bright nucleus. NGC 4945 is a spiral galaxy seen edge-on from Earth, 13 million light-years away. It is visible with any amateur telescope, as well as binoculars under good conditions; it has been described as "shaped like a candle flame", being long and thin (16' by 3'). In the eyepiece of a large telescope, its southeastern dust lane becomes visible. Another galaxy is NGC 5102, found by star-hopping from Iota Centauri. In the eyepiece, it appears as an elliptical object 9 arcminutes by 2.5 arcminutes tilted on a southwest-northeast axis.