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NGC 3718
NGC 3718, also called Arp 214, is a galaxy located approximately 52 million light years from Earth in the constellation Ursa Major. It is either a lenticular or spiral galaxy. NGC 3718 has a warped, s-shape similar to NGC 6872. This may be due to gravitational interaction between it and NGC 3729, another spiral galaxy located 150,000 light-years away. NGC 3718 is a member of the Ursa Major Cluster. Hickson Compact Group South of NGC 3718 the Hickson Compact Group A Hickson Compact Group (abbreviation: HCG) is a collection of galaxies designated as published by Paul Hickson in 1982. The most famous group on Hickson's list of 100 objects is HCG 92, Stephan's Quintet. Hickson Compact Groups According to Hi ... #56 is located. HCG 56 is a compact group of galaxies of which 4 members are interacting with each other. This group is about 120 Mpc distant to our galaxy, which is about 8 times more distant than NGC 3718. Gallery File:NGC3718.jpg, NGC3718 and its companion NGC ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J2000
In astronomy, an epoch or reference epoch is a instant, moment in time used as a reference point for some time-varying astronomical quantity. It is useful for the celestial coordinates or orbital elements of a Astronomical object, celestial body, as they are subject to Perturbation (astronomy), perturbations and vary with time. These time-varying astronomical quantities might include, for example, the mean longitude or mean anomaly of a body, the node of its orbit relative to a reference plane, the direction of the apogee or Perihelion and aphelion, aphelion of its orbit, or the size of the major axis of its orbit. The main use of astronomical quantities specified in this way is to calculate other relevant parameters of motion, in order to predict future positions and velocities. The applied tools of the disciplines of celestial mechanics or its subfield orbital mechanics (for predicting orbital paths and positions for bodies in motion under the gravitational effects of other bodi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 3729
NGC 3729 is a barred spiral galaxy located in the constellation Ursa Major. It is located at a distance of circa 65 million light years from Earth, which, given its apparent dimensions, means that NGC 3729 is about 60,000 light years across. It was discovered by William Herschel on April 12, 1789. NGC 3729 has a bright nucleus embedded in a bar which measures 0.5 x 0.1 arcminutes. At the end of the bar lies a ring with knots. The outer part of the galaxy is formed by an asymmetric faint nebulosity with condensations. It is possible that the condensation is a disturbed satellite galaxy. In the centre of NGC 3729 is predicted to lie an intermediate-mass black hole, whose mass is estimated to be between 4 and 400 thousands (104.6 ± 1.0 ) based on Ks-band bulge luminosity. The galaxy has an inner ring which emits in far ultraviolet and H-alpha, which are considered to be markers of recent star formation activity. NGC 3729 is member of the M109 Group which is part of the south Ursa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC Objects
The ''New General Catalogue of Nebulae and Clusters of Stars'' (abbreviated NGC) is an astronomical catalogue of deep-sky objects compiled by John Louis Emil Dreyer in 1888. The NGC contains 7,840 objects, including galaxies, star clusters and emission nebulae. Dreyer published two supplements to the NGC in 1895 and 1908, known as the ''Index Catalogues'' (abbreviated IC), describing a further 5,386 astronomical objects. Thousands of these objects are best known by their NGC or IC numbers, which remain in widespread use. The NGC expanded and consolidated the cataloguing work of William and Caroline Herschel, and John Herschel's ''General Catalogue of Nebulae and Clusters of Stars''. Objects south of the celestial equator are catalogued somewhat less thoroughly, but many were included based on observation by John Herschel or James Dunlop. The NGC contained multiple errors, but attempts to eliminate them were made by the ''Revised New General Catalogue'' (RNGC) by Jack W. Sulenti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peculiar Galaxies
A peculiar galaxy is a galaxy of unusual size, shape, or composition. Between five and ten percent of known galaxies are categorized as peculiar. Astronomers have identified two types of peculiar galaxies: ''interacting galaxies'' and ''active galactic nuclei'' (AGN). When two galaxies come close to each other, their mutual gravitational forces can cause them to acquire highly irregular shapes. The terms 'peculiar galaxy' and 'interacting galaxy' have now become synonymous because the majority of peculiar galaxies attribute their forms to such gravitational forces. Formation Scientists hypothesize that many peculiar galaxies are formed by the collision of two or more galaxies. As such, peculiar galaxies tend to host more active galactic nuclei than normal galaxies, indicating that they contain supermassive black holes. Many peculiar galaxies experience starbursts, or episodes of rapid star formation, due to the galaxies merging. The periods of elevated star formation and the l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intermediate Spiral Galaxies
An intermediate spiral galaxy is a galaxy that is in between the classifications of a barred spiral galaxy and an unbarred spiral galaxy. It is designated as SAB in the galaxy morphological classification system devised by Gerard de Vaucouleurs. Subtypes are labeled as SAB0, SABa, SABb, or SABc, following a sequence analogous to the Hubble sequence for barred and unbarred spirals. The subtype (0, a, b, or c) is based on the relative prominence of the central bulge and how tightly wound the spiral arms Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work ''The Realm of the Nebulae'' [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hubble Space Telescope
The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most versatile, renowned both as a vital research tool and as a public relations boon for astronomy. The Hubble telescope is named after astronomer Edwin Hubble and is one of NASA's Great Observatories. The Space Telescope Science Institute (STScI) selects Hubble's targets and processes the resulting data, while the Goddard Space Flight Center (GSFC) controls the spacecraft. Hubble features a mirror, and its five main instruments observe in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum. Hubble's orbit outside the distortion of Earth's atmosphere allows it to capture extremely high-resolution images with substantially lower background light than ground-based telescopes. It has recorded some of the most detaile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dark Energy Spectroscopic Instrument
The Dark Energy Spectroscopic Instrument (DESI) is a scientific research instrument for conducting spectrographic astronomical surveys of distant galaxies. Its main components are a focal plane containing 5,000 fiber-positioning robots, and a bank of spectrographs which are fed by the fibers. The new instrument will enable an experiment to probe the expansion history of the universe and the mysterious physics of dark energy. The instrument is operated by the Lawrence Berkeley National Laboratory under funding from the US Department of Energy's Office of Science. Construction of the new instrument, now completed, was principally funded by the US Department of Energy's Office of Science, and by other numerous sources including the US National Science Foundation, the UK Science and Technology Facilities Council, France's Alternative Energies and Atomic Energy Commission, Mexico's National Council of Science and Technology, Spain's Ministry of Science and Innovation, by the Gordon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hickson Compact Group
A Hickson Compact Group (abbreviation: HCG) is a collection of galaxies designated as published by Paul Hickson in 1982. The most famous group on Hickson's list of 100 objects is HCG 92, Stephan's Quintet. Hickson Compact Groups According to Hickson: “Most compact groups contain a high fraction of galaxies having morphological or kinematical peculiarities, nuclear radio and infrared emission, and starburst or active galactic nuclei (AGN) activity. They contain large quantities of diffuse gas and are dynamically dominated by dark matter. They most likely form as subsystems within looser associations and evolve by gravitational processes. Strong galaxy interactions result and merging is expected to lead to the ultimate demise of the group. Compact groups are surprisingly numerous, and may play a significant role in galaxy evolution.” List Gallery Image:A fossil in the making.jpg, NGC 201 is a barred spiral galaxy similar to the Milky Way, a member of HCG 7 Image:A members- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ursa Major Cluster
The Ursa Major Cluster (Ursa Major I Cluster, UMa I ClG) is a spiral-rich galaxy cluster of the Virgo Supercluster. Some of its largest members are NGC 3631, NGC 3953, M109 on North (M109 Group) and NGC 3726, NGC 3938, NGC 4051 on South. The Ursa Major cluster is located at a distance of 18.6 megaparsecs (60 million light-years) and contains about 30% of the light emitted but only 5% of the mass of the nearby Virgo Cluster The Virgo Cluster is a large cluster of galaxies whose center is 53.8 ± 0.3 Mly (16.5 ± 0.1 Mpc) away in the constellation Virgo. Comprising approximately 1,300 (and possibly up to 2,000) member galaxies, the cluster forms the heart of the la .... External links * Galaxy clusters Virgo Supercluster Ursa Major (constellation) {{galaxy-cluster-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 6872
NGC 6872, also known as the Condor Galaxy, is a large barred spiral galaxy, barred spiral galaxy of galaxy morphological classification, type ' in the constellation Pavo (constellation), Pavo. It is from Earth and is approximately five billion years old. is interacting galaxy, interacting with the lenticular galaxy , which is less than one twelfth as large. The galaxy has two elongated arms with a stellar diameter of over , and a D25.5 Isophote, isophotal diameter of over , making it the List of largest galaxies, largest known spiral galaxy. It was discovered on 27 June 1835 by English astronomer John Herschel. Star formation rates When observed in the ultraviolet and mid-infrared, the central region and bar of show stellar population#Population II stars, old stars and low rates of star formation, with rates increasing along the spiral arms as distance from the core increases. The most active region of star formation, located in the northeast arm, shows a stellar flux around ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Aeronautics And Space Administration
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding the National Advisory Committee for Aeronautics (NACA), to give the U.S. space development effort a distinctly civilian orientation, emphasizing peaceful applications in space science. NASA has since led most American space exploration, including Project Mercury, Project Gemini, the 1968-1972 Apollo Moon landing missions, the Skylab space station, and the Space Shuttle. NASA supports the International Space Station and oversees the development of the Orion spacecraft and the Space Launch System for the crewed lunar Artemis program, Commercial Crew spacecraft, and the planned Lunar Gateway space station. The agency is also responsible for the Launch Services Program, which provides oversight of launch operations and countdown management for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galaxy
A galaxy is a system of stars, stellar remnants, interstellar gas, dust, dark matter, bound together by gravity. The word is derived from the Greek ' (), literally 'milky', a reference to the Milky Way galaxy that contains the Solar System. Galaxies, averaging an estimated 100 million stars, range in size from dwarfs with less than a hundred million stars, to the largest galaxies known – supergiants with one hundred trillion stars, each orbiting its galaxy's center of mass. Most of the mass in a typical galaxy is in the form of dark matter, with only a few percent of that mass visible in the form of stars and nebulae. Supermassive black holes are a common feature at the centres of galaxies. Galaxies are categorized according to their visual morphology as elliptical, spiral, or irregular. Many are thought to have supermassive black holes at their centers. The Milky Way's central black hole, known as Sagittarius A*, has a mass four million times greater than the Sun. As o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
