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29-495: NGC 4435 is a barred lenticular galaxy currently interacting with NGC 4438. Studies of the galaxy by the Spitzer Space Telescope revealed a relatively young (190 million years) stellar population within the galaxy's nucleus, which may have originated through the interaction with NGC 4438 compressing gas and dust in that region, triggering a starburst. It also appears to have a long tidal tail possibly caused by

58-462: A bar. The creation of the bar is generally thought to be the result of a density wave radiating from the center of the galaxy whose effects reshape the orbits of the inner stars. This effect builds over time to stars orbiting farther out, which creates a self-perpetuating bar structure. The bar structure is believed to act as a type of stellar nursery , channeling gas inwards from the spiral arms through orbital resonance , fueling star birth in

87-411: A displacement of the components of its interstellar medium - atomic hydrogen, molecular hydrogen , interstellar dust , and hot gas - in the direction of NGC 4435. This observation suggests both a tidal interaction with NGC 4435 and the effects of ram-pressure stripping as NGC 4438 moves at high speed through Virgo's intracluster medium , increased by the encounter between both galaxies. While there

116-415: A highly distorted disk , including long tidal tails due to the gravitational interactions with other galaxies in the cluster and its companion . The aforementioned features explain why sources differ as to its classification, defining it either as a lenticular or spiral galaxy. NGC 4438 also shows signs of a past, extended - but modest - starburst, a considerable deficiency of neutral hydrogen , as well as

145-523: A past encounter between the two. Given the high density of galaxies in the center of the Virgo galaxy cluster, it is possible that the three galaxies, NGC 4435, NGC 4438, and M86, have had past interactions. In the 2014 film Interstellar , "NGC 4438" along with specific observation data can be seen in Murphy Cooper (Jessica Chastain)'s notepad during the film's climactic sequence. As the presence of

174-426: A sign of galaxies reaching full maturity as the "formative years" end. A 2008 investigation found that only 20 percent of the spiral galaxies in the distant past possessed bars, compared with about 65 percent of their local counterparts. The general classification is "SB" (spiral barred). The sub-categories are based on how open or tight the arms of the spiral are. SBa types feature tightly bound arms. SBc types are at

203-557: A spherical galaxy with a equal to b , the number is 0, and the Hubble type is E0. While the limit in the literature is about E7, it has been known since 1966 that the E4 to E7 galaxies are misclassified lenticular galaxies with disks inclined at different angles to our line of sight. This has been confirmed through spectral observations revealing the rotation of their stellar disks. Hubble recognized that his shape classification depends both on

232-448: A supermassive black hole in the AGC of NGC 4438 is one of two leading theories, the galaxy is potentially that accessed by the wormhole in the film. Barred spiral galaxy A barred spiral galaxy is a spiral galaxy with a central bar-shaped structure composed of stars . Bars are found in about two thirds of all spiral galaxies in the local universe, and generally affect both

261-426: A typical globular cluster , but contain a considerable amount of dark matter not present in clusters. Most of these small galaxies may not be related to other ellipticals. The Hubble classification of elliptical galaxies contains an integer that describes how elongated the galaxy image is. The classification is determined by the ratio of the major ( a ) to the minor ( b ) axes of the galaxy's isophotes : Thus for

290-459: Is evidence to suggest that the environmental damage to the interstellar medium of NGC 4438 may have been caused by an off-center collision with NGC 4435 millions of years ago, a recent discovery of several filaments of ionized gas links NGC 4438 with the large neighboring elliptical galaxy Messier 86 , in addition to a discovery of gas and dust within M86 that may have been stripped from NGC 4438 during

319-409: Is redder and metal-rich, and another that is bluer and metal-poor. The dynamical properties of elliptical galaxies and the bulges of disk galaxies are similar, suggesting that they may be formed by the same physical processes, although this remains controversial. The luminosity profiles of both elliptical galaxies and bulges are well fit by Sersic's law , and a range of scaling relations between

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348-715: Is typically minimal; they may, however, undergo brief periods of star formation when merging with other galaxies. Elliptical galaxies are believed to make up approximately 10–15% of galaxies in the Virgo Supercluster , and they are not the dominant type of galaxy in the universe overall. They are preferentially found close to the centers of galaxy clusters . Elliptical galaxies range in size from dwarf ellipticals with tens of millions of stars, to supergiants of over one hundred trillion stars that dominate their galaxy clusters. Originally, Edwin Hubble hypothesized that elliptical galaxies evolved into spiral galaxies, which

377-411: Is very little interstellar matter (neither gas nor dust), which results in low rates of star formation , few open star clusters , and few young stars; rather elliptical galaxies are dominated by old stellar populations , giving them red colors. Large elliptical galaxies typically have an extensive system of globular clusters . They generally have two distinct populations of globular clusters: one that

406-476: The M–sigma relation which relates the velocity dispersion of the surrounding stars to the mass of the black hole at the center. Elliptical galaxies are preferentially found in galaxy clusters and in compact groups of galaxies . Unlike flat spiral galaxies with organization and structure, elliptical galaxies are more three-dimensional, without much structure, and their stars are in somewhat random orbits around

435-453: The "disky" normal and dwarf ellipticals , which contain disks. This is, however, an abuse of the nomenclature, as there are two types of early-type galaxy, those with disks and those without. Given the existence of ES galaxies with intermediate-scale disks, it is reasonable to expect that there is a continuity from E to ES, and onto the S0 galaxies with their large-scale stellar disks that dominate

464-545: The Nebulae , along with spiral and lenticular galaxies. Elliptical (E) galaxies are, together with lenticular galaxies (S0) with their large-scale disks, and ES galaxies with their intermediate scale disks, a subset of the "early-type" galaxy population. Most elliptical galaxies are composed of older, low-mass stars , with a sparse interstellar medium , and they tend to be surrounded by large numbers of globular clusters . Star formation activity in elliptical galaxies

493-541: The bar compromises the stability of the overall bar structure. Simulations show that many bars likely experience a "buckling" event in which a disturbance in the orbital resonances of stars in the bar structure leads to an inward collapse in which the bar becomes thicker and shorter though the exact mechanism behind this buckling instability remains hotly debated. Barred spiral galaxies with high mass accumulated in their center thus tend to have short, stubby bars. Such buckling phenomena are significantly suppressed and delayed by

522-411: The center. The largest galaxies are supergiant ellipticals, or type-cD galaxies . Elliptical galaxies vary greatly in both size and mass with diameters ranging from 3,000 light years to more than 700,000 light years, and masses from 10 to nearly 10 solar masses. This range is much broader for this galaxy type than for any other. The smallest, the dwarf elliptical galaxies , may be no larger than

551-406: The elliptical galaxies' structural parameters unify the population. Every massive elliptical galaxy contains a supermassive black hole at its center. Observations of 46 elliptical galaxies, 20 classical bulges, and 22 pseudobulges show that each contain a black hole at the center. The mass of the black hole is tightly correlated with the mass of the galaxy, evidenced through correlations such as

580-473: The galaxies are the spiral galaxy, elliptical galaxy and irregular galaxy. Although theoretical models of galaxy formation and evolution had not previously expected galaxies becoming stable enough to host bars very early in the universe's history, evidence has recently emerged of the existence of numerous spiral galaxies in the early universe. Barred galaxies are apparently predominant, with surveys showing that up to two-thirds of all spiral galaxies develop

609-624: The interaction; however, other studies suggest the apparent tail is actually foreground galactic cirrus within the Milky Way unrelated to NGC 4435. NGC 4438 is the most curious interacting galaxy in the Virgo Cluster, due to the uncertainty surrounding the energy mechanism that heats the nuclear source; this energy mechanism may be a starburst region, or a black hole-powered active galactic nucleus (AGN). Both hypotheses are currently under investigation by astronomers. This galaxy shows

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638-412: The intrinsic shape of the galaxy, as well as the angle with which the galaxy is observed. Hence, some galaxies with Hubble type E0 are actually elongated. It is sometimes said that there are two physical types of ellipticals: the giant ellipticals with slightly "boxy"-shaped isophotes, whose shapes result from random motion which is greater in some directions than in others (anisotropic random motion); and

667-456: The light at large radii. Dwarf spheroidal galaxies appear to be a distinct class: their properties are more similar to those of irregulars and late spiral-type galaxies. At the large end of the elliptical spectrum, there is further division, beyond Hubble's classification. Beyond gE giant ellipticals, lies D-galaxies and cD-galaxies . These are similar to their smaller brethren, but more diffuse, with large haloes that may as much belong to

696-521: The motions of stars and interstellar gas within spiral galaxies and can affect spiral arms as well. The Milky Way Galaxy , where the Solar System is located, is classified as a barred spiral galaxy. Edwin Hubble classified spiral galaxies of this type as "SB" (spiral, barred) in his Hubble sequence and arranged them into sub-categories based on how open the arms of the spiral are. SBa types feature tightly bound arms, while SBc types are at

725-483: The other extreme and have loosely bound arms. SBb galaxies lie in between. SBm describes somewhat irregular barred spirals. SB0 is a barred lenticular galaxy . of barred Magellanic spiral Elliptical galaxy An elliptical galaxy is a type of galaxy with an approximately ellipsoidal shape and a smooth, nearly featureless image. They are one of the four main classes of galaxy described by Edwin Hubble in his Hubble sequence and 1936 work The Realm of

754-479: The other extreme and have loosely bound arms. SBb-type galaxies lie in between the two. SB0 is a barred lenticular galaxy . A new type, SBm, was subsequently created to describe somewhat irregular barred spirals , such as the Magellanic Clouds , which were once classified as irregular galaxies, but have since been found to contain barred spiral structures. Among other types in Hubble's classifications for

783-409: The presence of a supermassive black hole in the galactic center but occur nonetheless. Since so many spiral galaxies have bar structures, it is likely that they are recurring phenomena in spiral galaxy development. The oscillating evolutionary cycle from spiral galaxy to barred spiral galaxy is thought to take on average about two billion years. Recent studies have confirmed the idea that bars are

812-495: The vicinity of its center. This process is also thought to explain why many barred spiral galaxies have active galactic nuclei , such as that seen in the Southern Pinwheel Galaxy . Bars are thought to be temporary phenomena in the lives of spiral galaxies; the bar structures decay over time, transforming galaxies from barred spirals to more "regular" spiral patterns. Past a certain size the accumulated mass of

841-465: Was later discovered to be false, although the accretion of gas and smaller galaxies may build a disk around a pre-existing ellipsoidal structure. Stars found inside of elliptical galaxies are on average much older than stars found in spiral galaxies. Elliptical galaxies are characterized by several properties that make them distinct from other classes of galaxy. They are spherical or ovoid masses of stars, starved of star-making gases. Furthermore, there

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