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Henry Crozier Plummer
Henry Crozier Keating Plummer FRS FRAS (24 October 1875 – 30 September 1946) was an English astronomer. Early years and education Born in Oxford, Plummer was the son of William Edward Plummer (1849–1928) and nephew of the distinguished astronomer John Isaac Plummer (1845-1925). He gained his education at St. Edward's School and then Hertford College at Oxford University. After studies in physics, he became a lecturer at Owen's College, Manchester, instructing in mathematics. Career In 1900, he became an assistant at the Radcliffe Observatory, Oxford, where his father had served previously. He remained there for most of the next twelve years, spending one year at Lick Observatory as a Research Fellow. In 1912, he was appointed to the position of Andrews Professor of Astronomy at Trinity College, Dublin, which carried with it the title of Royal Astronomer of Ireland. He was the last holder of both positions. He was the director of the Dunsink Observatory from 1912 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fellow Of The Royal Society
Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural science, natural knowledge, including mathematics, engineering science, and medical science". Fellow, Fellowship of the Society, the oldest known scientific academy in continuous existence, is a significant honour. It has been awarded to many eminent scientists throughout history, including Isaac Newton (1672), Michael Faraday (1824), Charles Darwin (1839), Ernest Rutherford (1903), Srinivasa Ramanujan (1918), Albert Einstein (1921), Paul Dirac (1930), Winston Churchill (1941), Subrahmanyan Chandrasekhar (1944), Dorothy Hodgkin (1947), Alan Turing (1951), Lise Meitner (1955) and Francis Crick (1959). More recently, fellowship has been awarded to Stephen Hawking (1974), David Attenborough (1983), Tim Hunt (1991), Elizabeth Blackburn (1992), Tim Berners-Lee (2001), Venki R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dunsink Observatory
The Dunsink Observatory is an astronomical observatory established in 1785 in the townland of Dunsink in the outskirts of the city of Dublin, Ireland.Alexander Thom''Irish Almanac and Official Directory''7th ed., 1850 p. 258. Retrieved: 2011-02-22. Dunsink's most famous director was William Rowan Hamilton, who, amongst other things, discovered quaternions, the first non-commutative algebra form, while walking from the observatory to the city with his wife. The annual Hamilton Walk that commemorates this discovery begins at the observatory. He is also renowned for his Hamiltonian formulation of dynamics. History The observatory was established by an endowment of £3,000 in the will of Francis Andrews, who was Provost of Trinity College Dublin at his death on 18 June 1774. The site was established on the south slope of a low hill in the townland of Dunsink, 84m above sea level. The South Telescope, a 12-inch Grubb instrument, is a refracting (i.e. it uses lens) telescope built ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Academics Of The University Of Oxford
An academy (Attic Greek: Ἀκαδήμεια; Koine Greek Ἀκαδημία) is an institution of secondary or tertiary higher learning (and generally also research or honorary membership). The name traces back to Plato's school of philosophy, founded approximately 385 BC at Akademia, a sanctuary of Athena, the goddess of wisdom and skill, north of Athens, Greece. Etymology The word comes from the ''Academy'' in ancient Greece, which derives from the Athenian hero, ''Akademos''. Outside the city walls of Athens, the gymnasium was made famous by Plato as a center of learning. The sacred space, dedicated to the goddess of wisdom, Athena, had formerly been an olive grove, hence the expression "the groves of Academe". In these gardens, the philosopher Plato conversed with followers. Plato developed his sessions into a method of teaching philosophy and in 387 BC, established what is known today as the Old Academy. By extension, ''academia'' has come to mean the accumulation, d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1946 Deaths
Events January * January 6 - The first general election ever in Vietnam is held. * January 7 – The Allies recognize the Austrian republic with its 1937 borders, and divide the country into four occupation zones. * January 10 ** The first meeting of the United Nations is held, at Methodist Central Hall Westminster in London. ** ''Project Diana'' bounces radar waves off the Moon, measuring the exact distance between the Earth and the Moon, and proves that communication is possible between Earth and outer space, effectively opening the Space Age. * January 11 - Enver Hoxha declares the People's Republic of Albania, with himself as prime minister. * January 16 – Charles de Gaulle resigns as head of the French provisional government. * January 17 - The United Nations Security Council holds its first session, at Church House, Westminster in London. * January 19 ** The Bell XS-1 is test flown for the first time (unpowered), with Bell's chief test pilot Jack Woolams at t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1875 Births
Events January–March * January 1 – The Midland Railway of England abolishes the Second Class passenger category, leaving First Class and Third Class. Other British railway companies follow Midland's lead during the rest of the year (Third Class is renamed Second Class in 1956). * January 5 – The Palais Garnier, one of the most famous opera houses in the world, is inaugurated in Paris. * January 12 – Guangxu Emperor, Guangxu becomes the 11th Qing Dynasty Emperor of China at the age of 3, in succession to his cousin. * January 14 – The newly proclaimed King Alfonso XII of Spain (Queen Isabella II's son) arrives in Spain to restore the monarchy during the Third Carlist War. * February 3 – Third Carlist War – Battle of Lácar: Carlist commander Torcuato Mendiri, Torcuato Mendíri secures a brilliant victory, when he surprises and routs a Government force under General Enrique Bargés at Lácar, east of Estella, nearly capturing newly cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monthly Notices Of The Royal Astronomical Society
''Monthly Notices of the Royal Astronomical Society'' (MNRAS) is a peer-reviewed scientific journal covering research in astronomy and astrophysics. It has been in continuous existence since 1827 and publishes letters and papers reporting original research in relevant fields. Despite the name, the journal is no longer monthly, nor does it carry the notices of the Royal Astronomical Society. History The first issue of MNRAS was published on 9 February 1827 as ''Monthly Notices of the Astronomical Society of London'' and it has been in continuous publication ever since. It took its current name from the second volume, after the Astronomical Society of London became the Royal Astronomical Society (RAS). Until 1960 it carried the monthly notices of the RAS, at which time these were transferred to the newly established ''Quarterly Journal of the Royal Astronomical Society'' (1960–1996) and then to its successor journal ''Astronomy & Geophysics'' (since 1997). Until 1965, MNRAS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
On The Theory Of Aberration And The Principle Of Relativity
On, on, or ON may refer to: Arts and entertainment Music * On (band), a solo project of Ken Andrews * ''On'' (EP), a 1993 EP by Aphex Twin * ''On'' (Echobelly album), 1995 * ''On'' (Gary Glitter album), 2001 * ''On'' (Imperial Teen album), 2002 * ''On'' (Elisa album), 2006 * ''On'' (Jean album), 2006 * ''On'' (Boom Boom Satellites album), 2006 * ''On'' (Tau album), 2017 * "On" (song), a 2020 song by BTS * "On", a song by Bloc Party from the 2006 album ''A Weekend in the City'' Other media * ''Ön'', a 1966 Swedish film * On (Japanese prosody), the counting of sound units in Japanese poetry * ''On'' (novel), by Adam Roberts * ONdigital, a failed British digital television service, later called ITV Digital * Overmyer Network, a former US television network Places * On (Ancient Egypt), a Hebrew form of the ancient Egyptian name of Heliopolis * On, Wallonia, a district of the municipality of Marche-en-Famenne * Ahn, Luxembourg, known in Luxembourgish as ''On'' * Ontario, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plummer (crater)
Plummer is a lunar impact crater. It is located on the far side of the Moon from the Earth, to the north of the huge walled plain Apollo Apollo, grc, Ἀπόλλωνος, Apóllōnos, label=genitive , ; , grc-dor, Ἀπέλλων, Apéllōn, ; grc, Ἀπείλων, Apeílōn, label= Arcadocypriot Greek, ; grc-aeo, Ἄπλουν, Áploun, la, Apollō, la, Apollinis, label .... Less than one crater diameter to the north of Plummer is the similar-sized Wilsing. This is a worn crater formation with several notable impacts along the rim. The largest of these is the satellite crater Plummer M intruding into the southern rim. Slightly smaller is Plummer W overlapping part of the northwestern outer rim. There is also a relatively fresh crater cutting across the eastern rim. The interior floor of Plummer is marked by only a few tiny craterlets, and a central peak offset just to the east of the midpoint. Satellite craters By convention these features are identified on lunar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Society
The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, recognising excellence in science, supporting outstanding science, providing scientific advice for policy, education and public engagement and fostering international and global co-operation. Founded on 28 November 1660, it was granted a royal charter by King Charles II as The Royal Society and is the oldest continuously existing scientific academy in the world. The society is governed by its Council, which is chaired by the Society's President, according to a set of statutes and standing orders. The members of Council and the President are elected from and by its Fellows, the basic members of the society, who are themselves elected by existing Fellows. , there are about 1,700 fellows, allowed to use the postnominal title FRS (Fellow of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isaac Newton
Sir Isaac Newton (25 December 1642 – 20 March 1726/27) was an English mathematician, physicist, astronomer, alchemist, theologian, and author (described in his time as a "natural philosopher"), widely recognised as one of the greatest mathematicians and physicists and among the most influential scientists of all time. He was a key figure in the philosophical revolution known as the Enlightenment. His book (''Mathematical Principles of Natural Philosophy''), first published in 1687, established classical mechanics. Newton also made seminal contributions to optics, and shares credit with German mathematician Gottfried Wilhelm Leibniz for developing infinitesimal calculus. In the , Newton formulated the laws of motion and universal gravitation that formed the dominant scientific viewpoint for centuries until it was superseded by the theory of relativity. Newton used his mathematical description of gravity to derive Kepler's laws of planetary motion, account for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plummer Model
The Plummer model or Plummer sphere is a density law that was first used by H. C. Plummer to fit observations of globular clusters. It is now often used as toy model in N-body simulations of stellar systems. Description of the model The Plummer 3-dimensional density profile is given by : \rho_P(r) = \frac \left(1 + \frac\right)^, where ''M_0'' is the total mass of the cluster, and ''a'' is the Plummer radius, a scale parameter that sets the size of the cluster core. The corresponding potential is : \Phi_P(r) = -\frac, where ''G'' is Newton's gravitational constant. The velocity dispersion is : \sigma_P^2(r) = \frac. The distribution function is : f(\vec, \vec) = \frac \frac (-E(\vec, \vec))^, if E < 0, and otherwise, where is the .
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Cepheid Variable
A Cepheid variable () is a type of star that pulsates radially, varying in both diameter and temperature and producing changes in brightness with a well-defined stable period and amplitude. A strong direct relationship between a Cepheid variable's luminosity and pulsation period established Cepheids as important indicators of cosmic benchmarks for scaling galactic and extragalactic distances. This robust characteristic of classical Cepheids was discovered in 1908 by Henrietta Swan Leavitt after studying thousands of variable stars in the Magellanic Clouds. This discovery allows one to know the true luminosity of a Cepheid by simply observing its pulsation period. This in turn allows one to determine the distance to the star, by comparing its known luminosity to its observed brightness. The term ''Cepheid'' originates from Delta Cephei in the constellation Cepheus, identified by John Goodricke in 1784, the first of its type to be so identified. The mechanics of stellar pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
