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NGC 2608
NGC 2608 (also known as Arp 12) is a barred spiral galaxy located 93 million light-years away in the constellation Cancer (the Crab). It was discovered by German-British astronomer William Herschel on 12 March 1785. It spans 62,000 light-years, approximately 60% of the Milky Way's diameter. It is considered a grand design spiral galaxy and is classified as SB(s)b, meaning that the galaxy's arms wind moderately (neither tightly nor loosely) around the prominent central bar. It was classified under "galaxies with split arms" in the 1966 ''Atlas of Peculiar Galaxies'' by Halton Arp, who noted that the "nucleus may be double or superimposed star". NGC 2608 is now thought to be a pair of interacting galaxies. Supernovae *SN 1920A was discovered on 8 February 1920, with an apparent magnitude of 12.9, by German astronomer Max Wolf (1863–1932). It reached peak brightness on 15 February 1920 at magnitude 12.05. Its visual magnitude implies an overluminous bolometric magnitude; SN ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Max Wolf
Maximilian Franz Joseph Cornelius Wolf (21 June 1863 – 3 October 1932) was a German astronomer and a pioneer in the field of astrophotography. He was the chairman of astronomy at the University of Heidelberg and director of the Heidelberg-Königstuhl State Observatory from 1902 until his death in 1932. Early life Max Wolf was born in Heidelberg, Germany on 21 June 1863, the son of medical doctor Franz Wolf. His father encouraged an interest in science and built an observatory for his son in the garden of the family home. It is from here that Wolf was credited with his first astronomical discovery, comet 14P/Wolf, in 1884. Life at the university Wolf attended his local university and, in 1888, at the age of 25, was awarded a Doctor of Philosophy, Ph.D. by the University of Heidelberg. He spent one year of post-graduate study in Stockholm, the only significant time he would spend outside of Heidelberg in his life. He returned to the University of Heidelberg and accepted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New General Catalogue
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 galaxy, 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 Herschel, William and Caroline Herschel, and John Herschel's ''General Catalogue of Nebulae and Clusters of Stars''. Objects south of the Celestial sphere, 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 Ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halton Arp
Halton Christian "Chip" Arp (March 21, 1927 – December 28, 2013) was an American astronomer. He is remembered for his 1966 book ''Atlas of Peculiar Galaxies'', which catalogued unusual-looking galaxies and presented their images. Arp was also known as a critic of the Big Bang theory and for advocating a non-standard cosmology incorporating intrinsic redshift. Arp developed those views in a book, ''Seeing Red: Redshift, Cosmology and Academic Science'', in 1998.Halton Arp, ''Seeing Red: Redshift, Cosmology and Academic Science'', Montreal: Aperion (1998), pp. 14, 61–62, 72, 104–105 Biography Arp was born on March 21, 1927, in New York City. He was married three times and has four daughters, including comic artist Andrice Arp, and five grandchildren. His bachelor's degree was awarded by Harvard College, Harvard (1949), and his PhD by California Institute of Technology, Caltech (1953). Afterward he became a Fellow of the Carnegie Institution of Washington in 1953, perfor ... [...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. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arp Objects
The ''Atlas of Peculiar Galaxies'' is a Astronomical catalog, 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. (online version, including Arp's original tabular data, and PDF link) Background Arp realized that the reason why galaxies formed into spiral galaxy, spiral or elliptical galaxy, elliptical shapes was not well understood. He perceived peculiar galaxies as small "experiments" that astronomers could use to understand the physical processes that distort spiral or elliptical galaxies. With this atlas, astronomers had a sample of peculiar galaxies that they could study in more detail. The atlas does not present a complete overview of every peculiar galaxy in the sky but instead provides exam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barred Spiral Galaxies
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 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 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of NGC Objects (2001-3000)
The following is a list of NGC objects, that is objects listed in the New General Catalogue (NGC). It is one of the largest comprehensive astronomical catalogues for deep sky objects such as star clusters, nebulae, and galaxies. *List of NGC objects (1–1000) *List of NGC objects (1001–2000) *List of NGC objects (2001–3000) *List of NGC objects (3001–4000) *List of NGC objects (4001–5000) *List of NGC objects (5001–6000) *List of NGC objects (6001–7000) *List of NGC objects (7001–7840) Stars Some objects originally thought to be deep sky objects and listed in the NGC have been subsequently shown to be ordinary stars, so their inclusion in the catalog is now considered erroneous. This list of stars is based on the "NGC 2000.0" version of the catalog, which lists the stars in its errata, supplemented with data on each individual star from the VizieR database. See also * Lists of astronomical objects This is a list of lists, grouped by type of astronomical objec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type Ia Supernova
A Type Ia supernova (read: "type one-A") is a type of supernova that occurs in binary systems (two stars orbiting one another) in which one of the stars is a white dwarf. The other star can be anything from a giant star to an even smaller white dwarf. Physically, carbon–oxygen white dwarfs with a low rate of rotation are limited to below 1.44 solar masses (). Beyond this "Chandrasekhar limit, critical mass", they reignite and in some cases trigger a supernova explosion; this critical mass is often referred to as the Chandrasekhar mass, but is marginally different from the absolute Chandrasekhar limit, where electron degeneracy pressure is unable to prevent catastrophic collapse. If a white dwarf gradually accretes mass from a binary companion, or merges with a second white dwarf, the general hypothesis is that a white dwarf's core will reach the ignition temperature for Carbon burning process, carbon fusion as it approaches the Chandrasekhar mass. Within a few seconds of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectral Lines
A spectral line is a weaker or stronger region in an otherwise uniform and continuous spectrum. It may result from emission or absorption of light in a narrow frequency range, compared with the nearby frequencies. Spectral lines are often used to identify atoms and molecules. These "fingerprints" can be compared to the previously collected ones of atoms and molecules, and are thus used to identify the atomic and molecular components of stars and planets, which would otherwise be impossible. Types of line spectra Spectral lines are the result of interaction between a quantum system (usually atoms, but sometimes molecules or atomic nuclei) and a single photon. When a photon has about the right amount of energy (which is connected to its frequency) to allow a change in the energy state of the system (in the case of an atom this is usually an electron changing orbitals), the photon is absorbed. Then the energy will be spontaneously re-emitted, either as one photon at the same ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apparent Magnitude
Apparent magnitude () is a measure of the Irradiance, brightness of a star, astronomical object or other celestial objects like artificial satellites. Its value depends on its intrinsic luminosity, its distance, and any extinction (astronomy), extinction of the object's light caused by interstellar dust along the sightline, line of sight to the observer. Unless stated otherwise, the word ''magnitude'' in astronomy usually refers to a celestial object's apparent magnitude. The magnitude scale likely dates to before the ancient Ancient Greek astronomy#Astronomy in the Greco-Roman and Late Antique eras, Roman astronomer Ptolemy, Claudius Ptolemy, whose Star catalogue, star catalog popularized the system by listing stars from First-magnitude star, 1st magnitude (brightest) to 6th magnitude (dimmest). The modern scale was mathematically defined to closely match this historical system by Norman Robert Pogson, Norman Pogson in 1856. The scale is reverse logarithmic scale, logarithmic: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tom Boles
Thomas Boles (born 1944 in Lennoxtown in Scotland) is a Scottish amateur astronomer, discoverer of astronomical objects, author, broadcaster and former communications and computer engineer, who observes from his private "Coddenham Observatory" () in Coddenham, Suffolk, United Kingdom. He is known for having discovered a record number of supernovae. The main-belt asteroid 7648 Tomboles is named in his honor. He was President of the British Astronomical Association from 2003 to 2005 and Vice President from 2005 to 2007. He is a Fellow of the Royal Astronomical Society and an Examinations Moderator in astronomy with the International Baccalaureate. At the International Astronomical Union, he was a member of ''Division VIII Galaxies & the Universe'' and "Commission 28" until 2012 and 2015, respectively, and is a member of IAU's division C and J (Education, Outreach and Heritage; Galaxies and Cosmology). Boles has co-authored three text books on popular astronomy and has published ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
