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Boyden Station
Boyden Observatory is an astronomical research observatory and science education centre located in Maselspoort, north-east of the city of Bloemfontein in Free State, South Africa. The observatory is managed by the Physics Department of the University of the Free State (UFS). The Friends of Boyden assist the observatory as a public support group, organising open evenings and protecting its public interest. Boyden also makes use of members of ASSA Bloemfontein Centre, the amateur astronomy club of the city, for presenters and telescope assistants. History The Boyden Station of Harvard Observatory was founded in 1889 by Harvard University at Mount Harvard near Lima, Peru. It was relocated to Arequipa, Peru in October 1890 ( obs. code: 800). It was named after Uriah A. Boyden, who in 1879 left in his will $238,000 to Harvard Observatory to be used for astronomical purposes. Significant work done at Arequipa include the discovery of Phoebe, an outer moon of Saturn, by William ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of The Free State
The University of the Free State is a multi-campus public university in Bloemfontein, the capital of the Free State (province), Free State and the judicial capital of South Africa. It was first established as an institution of higher learning in 1904 as a tertiary section of Grey College, Bloemfontein, Grey College. It was declared an independent Afrikaans-language university in 1950 and the name was changed to the University of the Orange Free State. The university has two satellite campuses. Initially a whites-only precinct, the university was fully de-segregated in 1996. The first black university vice-chancellor was appointed in 2010. History The long-held dream of an institution of higher education in the Free State became a reality in 1904 when the Grey College, Bloemfontein, Grey College first accepted matriculants for a full B.A. course. In 1906 the tertiary part of Grey College became known as the Grey University College (GUC), but shortly thereafter the school and colle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Henry Pickering
William Henry Pickering (February 15, 1858 – January 16, 1938) was an American astronomer. Pickering constructed and established several observatories or astronomical observation stations, notably including Percival Lowell's Flagstaff Observatory. He led solar eclipse expeditions and studied craters on the Moon, and hypothesized that changes in the appearance of the crater Eratosthenes were due to "lunar insects". He spent much of the later part of his life at his private observatory in Jamaica. Biography William Pickering was born on February 15, 1858 in Boston, Massachusetts. His older brother was Edward Charles Pickering, director of the Harvard College Observatory for three decades. He graduated from the Massachusetts Institute of Technology in 1879 then became an instructor in physics from 1880 to 1887. He was elected a Fellow of the American Academy of Arts and Sciences in 1883 at age 25. He discovered Saturn's ninth moon Phoebe in 1899 from plates taken in 1898. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Telescope
A solar telescope is a special purpose telescope used to observe the Sun. Solar telescopes usually detect light with wavelengths in, or not far outside, the visible spectrum. Obsolete names for Sun telescopes include heliograph and photoheliograph. Professional solar telescopes Solar telescopes need optics large enough to achieve the best possible diffraction limit but less so for the associated light-collecting power of other astronomical telescopes. However, recently newer narrower filters and higher framerates have also driven solar telescopes towards photon-starved operations. Both the Daniel K. Inouye Solar Telescope as well as the proposed European Solar Telescope (EST) have larger apertures not only to increase the resolution, but also to increase the light-collecting power. Because solar telescopes operate during the day, seeing is generally worse than for night-time telescopes, because the ground around the telescope is heated which causes turbulence and degrades the res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Wilson Observatory
The Mount Wilson Observatory (MWO) is an astronomical observatory in Los Angeles County, California, United States. The MWO is located on Mount Wilson, a peak in the San Gabriel Mountains near Pasadena, northeast of Los Angeles. The observatory contains two historically important telescopes: the Hooker telescope, which was the largest aperture telescope in the world from its completion in 1917 to 1949, and the 60-inch telescope which was the largest operational telescope in the world when it was completed in 1908. It also contains the Snow solar telescope completed in 1905, the 60 foot (18 m) solar tower completed in 1908, the 150 foot (46 m) solar tower completed in 1912, and the CHARA array, built by Georgia State University, which became fully operational in 2004 and was the largest optical interferometer in the world at its completion. Due to the inversion layer that traps warm air and smog over Los Angeles, Mount Wilson has steadier air than any other location in Nor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alvan Clark
Alvan Clark (March 8, 1804 – August 19, 1887), born in Ashfield, Massachusetts, the descendant of a Cape Cod whaling family of English ancestry, was an American astronomer and telescope maker. Biography He started as a portrait painter and engraver (c.1830s-1850s), and at the age of 40 became involved in telescope making. Using glass blanks made by Chance Brothers of Birmingham and Feil-Mantois of Paris, his firm '' Alvan Clark & Sons'' ground lenses for refracting telescopes. Their lenses included the largest in the world at the time: the at Dearborn Observatory at the Old University of Chicago (the lens was originally intended for Ole Miss), the two telescopes at the United States Naval Observatory and McCormick Observatory, the at Pulkovo Observatory (destroyed in the Siege of Leningrad; only the lens survives), the telescope at Lick Observatory (still third-largest) and later the at Yerkes Observatory, which remains the largest successful refracting telescope in the wor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refractor
A refracting telescope (also called a refractor) is a type of optical telescope that uses a lens (optics), lens as its objective (optics), objective to form an image (also referred to a dioptrics, dioptric telescope). The refracting telescope design was originally used in spyglasses and astronomy, astronomical telescopes but is also used for long-focus lens, long-focus camera lenses. Although large refracting telescopes were very popular in the second half of the 19th century, for most research purposes, the refracting telescope has been superseded by the reflecting telescope, which allows larger apertures. A refractor's magnification is calculated by dividing the focal length of the objective lens by that of the eyepiece. Refracting telescopes typically have a lens at the front, then a optical train, long tube, then an eyepiece or instrumentation at the rear, where the telescope view comes to focus. Originally, telescopes had an objective of one element, but a century later, tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nagoya University
, abbreviated to or NU, is a Japanese national research university located in Chikusa-ku, Nagoya. It was the seventh Imperial University in Japan, one of the first five Designated National University and selected as a Top Type university of Top Global University Project by the Japanese government. It is the 3rd highest ranked higher education institution in Japan (84th worldwide). The university is the birthplace of the Sakata School of physics and the Hirata School of chemistry. As of 2021, seven Nobel Prize winners have been associated with Nagoya University, the third most in Japan and Asia behind Kyoto University and the University of Tokyo. History Nagoya University traces its roots back to 1871 when it was the Temporary Medical School/Public Hospital. In 1939 it became Nagoya Imperial University (), the last Imperial University of Japanese Empire. In 1947 it was renamed Nagoya University (), and became a Japanese national university. In 2014, according to the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reflecting Telescope
A reflecting telescope (also called a reflector) is a telescope that uses a single or a combination of curved mirrors that reflect light and form an image. The reflecting telescope was invented in the 17th century by Isaac Newton as an alternative to the refracting telescope which, at that time, was a design that suffered from severe chromatic aberration. Although reflecting telescopes produce other types of optical aberrations, it is a design that allows for very large diameter objectives. Almost all of the major telescopes used in astronomy research are reflectors. Many variant forms are in use and some employ extra optical elements to improve image quality or place the image in a mechanically advantageous position. Since reflecting telescopes use mirrors, the design is sometimes referred to as a catoptrics, catoptric telescope. From the time of Newton to the 1800s, the mirror itself was made of metal usually speculum metal. This type included Newton's first designs and eve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma-ray Burst
In gamma-ray astronomy, gamma-ray bursts (GRBs) are immensely energetic explosions that have been observed in distant galaxies. They are the most energetic and luminous electromagnetic events since the Big Bang. Bursts can last from ten milliseconds to several hours. After an initial flash of gamma rays, a longer-lived "afterglow" is usually emitted at longer wavelengths (X-ray, ultraviolet, optical, infrared, microwave and radio). The intense radiation of most observed GRBs is thought to be released during a supernova or superluminous supernova as a high-mass star implodes to form a neutron star or a black hole. A subclass of GRBs appear to originate from the merger of binary neutron stars. The sources of most GRBs are billions of light years away from Earth, implying that the explosions are both extremely energetic (a typical burst releases as much energy in a few seconds as the Sun will in its entire 10-billion-year lifetime) and extremely rare (a few per galaxy per milli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University College Dublin
University College Dublin (commonly referred to as UCD) ( ga, Coláiste na hOllscoile, Baile Átha Cliath) is a public research university in Dublin, Ireland, and a collegiate university, member institution of the National University of Ireland. With 33,284 students, it is Ireland's largest university, and amongst the most prestigious universities in the country. Five Nobel Laureates are among UCD's alumni and current and former staff. Additionally, four Irish Taoiseach (Prime Ministers) and three Irish Presidents have graduated from UCD, along with one President of India. UCD originates in a body founded in 1854, which opened as the Catholic University of Ireland on the feast of Saint Malachy, St. Malachy with John Henry Newman as its first rector; it re-formed in 1880 and chartered in its own right in 1908. The Universities Act, 1997 renamed the constituent university as the "National University of Ireland, Dublin", and a ministerial order of 1998 renamed the institution as "U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robotic Telescope
A robotic telescope is an astronomical telescope and detector system that makes observations without the intervention of a human. In astronomical disciplines, a telescope qualifies as robotic if it makes those observations without being operated by a human, even if a human has to initiate the observations at the beginning of the night or end them in the morning. It may have software agents using artificial intelligence that assist in various ways such as automatic scheduling. A robotic telescope is distinct from a remote telescope, though an instrument can be both robotic and remote. By 2004, robotic observations accounted for an overwhelming percentage of the published scientific information on asteroid orbits and discoveries, variable star studies, supernova light curves and discoveries, comet orbits and gravitational microlensing observations. All early phase gamma ray burst observations were carried by robotic telescopes. Design Robotic telescopes are complex systems that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
F-number
In optics, the f-number of an optical system such as a camera lens is the ratio of the system's focal length to the diameter of the entrance pupil ("clear aperture").Smith, Warren ''Modern Optical Engineering'', 4th Ed., 2007 McGraw-Hill Professional, p. 183. It is also known as the focal ratio, f-ratio, or f-stop, and is very important in photography. It is a dimensionless number that is a quantitative measure of lens speed; increasing the f-number is referred to as ''stopping down''. The f-number is commonly indicated using a lower-case hooked f with the format ''N'', where ''N'' is the f-number. The f-number is the reciprocal of the relative aperture (the aperture diameter divided by focal length). Notation The f-number is given by: N = \frac \ where f is the focal length, and D is the diameter of the entrance pupil (''effective aperture''). It is customary to write f-numbers preceded by "", which forms a mathematical expression of the entrance pupil diameter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
