![]() ![]() It was then the only known elliptical nebula for which individual stars could be resolved, although it was pointed out that globular clusters would be indistinguishable from individual stars at such distances. In 1931, Hubble described M87 as a member of the Virgo Cluster, and gave a provisional estimate of 1.8 million parsecs (5.9 million light-years) from Earth. M87 was classified as a type of elliptical extragalactic nebula with no apparent elongation (class E0). In 1926 he produced a new categorization, distinguishing extragalactic from galactic nebulae, the former being independent star systems. In 1922, the American astronomer Edwin Hubble categorized M87 as one of the brighter globular nebulae, as it lacked any spiral structure, but like spiral nebulae, appeared to belong to the family of non-galactic nebulae. In Hubble's galaxy classification scheme, M87 is an E0 galaxy. The following year, supernova SN 1919A within M87 reached a peak photographic magnitude of 21.5, although this event was not reported until photographic plates were examined by the Russian astronomer Innokentii A. apparently connected with the nucleus by a thin line of matter." The ray appeared brightest near the galactic center. In 1918, the American astronomer Heber Curtis of Lick Observatory noted M87's lack of a spiral structure and observed a "curious straight ray. During the 1880s, the object was included as NGC 4486 in the New General Catalogue of nebulae and star clusters assembled by the Danish-Irish astronomer John Dreyer, which he based primarily on the observations of the English astronomer John Herschel. Thus, M87 was the eighty-seventh object listed in Messier's catalogue. In subsequent use, each catalogue entry was prefixed with an "M". In 1781, the French astronomer Charles Messier published a catalogue of 103 objects that had a nebulous appearance as part of a list intended to identify objects that might otherwise be confused with comets. Its interstellar medium consists of diffuse gas enriched by elements emitted from evolved stars. It has an isophotal diameter of 40.55 kiloparsecs (132,000 light-years), with a diffuse galactic envelope that extends to a radius of about 150 kiloparsecs (490,000 light-years), where it is truncated-possibly by an encounter with another galaxy. The galaxy is a strong source of multi-wavelength radiation, particularly radio waves. In March 2021, the EHT Collaboration presented, for the first time, a polarized-based image of the black hole which may help better reveal the forces giving rise to quasars. The black hole was imaged using data collected in 2017 by the Event Horizon Telescope (EHT), with a final, processed image released on 10 April 2019. It has an active supermassive black hole at its core, which forms the primary component of an active galactic nucleus. Their population density decreases with increasing distance from the core. ![]() Forming around one-sixth of its mass, M87's stars have a nearly spherically symmetric distribution. Instead, it has an almost featureless, ellipsoidal shape typical of most giant elliptical galaxies, diminishing in luminosity with distance from the center. Unlike a disk-shaped spiral galaxy, M87 has no distinctive dust lanes. M87 is about 16.4 million parsecs (53 million light-years) from Earth and is the second-brightest galaxy within the northern Virgo Cluster, having many satellite galaxies. The French astronomer Charles Messier discovered M87 in 1781, and cataloged it as a nebula. It is one of the brightest radio sources in the sky and a popular target for both amateur and professional astronomers. ![]() One of the largest and most massive galaxies in the local universe, it has a large population of globular clusters-about 15,000 compared with the 150–200 orbiting the Milky Way-and a jet of energetic plasma that originates at the core and extends at least 1,500 parsecs (4,900 light-years), traveling at a relativistic speed. Messier 87 (also known as Virgo A or NGC 4486, generally abbreviated to M87) is a supergiant elliptical galaxy in the constellation Virgo that contains several trillion stars. The galactic core of Messier 87, with its blue plasma jet clearly visible ( composite image of observations by the Hubble Space Telescope in visible and infrared light) ![]()
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