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LAMOST J0037 4016
The Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST), also known as the Guo Shoujing Telescope (Chinese: 郭守敬望远镜) after the 13th-century Chinese astronomer, is a meridian reflecting Schmidt telescope, located in Xinglong Station, Hebei Province, China. Undertaken by the Chinese Academy of Sciences, the telescope is planned to conduct a 5-year spectroscopic survey of 10 million Milky Way stars, as well as millions of galaxies. The project's budget is RMB 235 million yuan. Optics LAMOST is configured as a reflective Schmidt telescope with active optics. There are two mirrors, each made up of a number of 1.1-metre (p-p) hexagonal deformable segments. The first mirror, MA (24 segments, fitting in a 5.72×4.4 m rectangle) is a Schmidt corrector plate in a dome at ground level. The almost-flat mirror MA reflects the light to the south, up a large slanted tunnel (25° above horizontal) to the larger spherical focusing mirror MB (37 segments, fittin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guo Shoujing
Guo Shoujing (, 1231–1316), courtesy name Ruosi (), was a Chinese astronomer, hydraulic engineer, mathematician, and politician of the Yuan dynasty. The later Johann Adam Schall von Bell (1591–1666) was so impressed with the preserved astronomical instruments of Guo that he called him "the Tycho Brahe of China." Jamal ad-Din cooperated with him. Early life In 1231, in Xingtai, Hebei province, China, Guo Shoujing was born into a poor family.O'Connor. He was raised primarily by his paternal grandfather, Guo Yong, who was famous throughout China for his expertise in a wide variety of topics, ranging from the study of the Five Classics to astronomy, mathematics, and hydraulics. Guo Shoujing was a child prodigy, showing exceptional intellectual promise. By his teens, he obtained a blueprint for a water clock which his grandfather was working on, and realized its principles of operation. He improved the design of a type of water clock called a lotus clepsydra, a water clock w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectral Resolution
The spectral resolution of a spectrograph, or, more generally, of a frequency spectrum, is a measure of its ability to resolve features in the electromagnetic spectrum. It is usually denoted by \Delta\lambda, and is closely related to the resolving power of the spectrograph, defined as R = \frac, where \Delta\lambda is the smallest difference in wavelengths that can be distinguished at a wavelength of \lambda. For example, the Space Telescope Imaging Spectrograph (STIS) can distinguish features 0.17 nm apart at a wavelength of 1000 nm, giving it a resolution of 0.17 nm and a resolving power of about 5,900. An example of a high resolution spectrograph is the ''Cryogenic High-Resolution IR Echelle Spectrograph'' (CRIRES+) installed at ESO's Very Large Telescope, which has a spectral resolving power of up to 100,000. Doppler effect The spectral resolution can also be expressed in terms of physical quantities, such as velocity; then it describes the difference between vel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Telescopes
An optical telescope is a telescope that gathers and focuses light mainly from the visible part of the electromagnetic spectrum, to create a magnified image for direct visual inspection, to make a photograph, or to collect data through electronic image sensors. There are three primary types of optical telescope: * Refracting telescopes, which use lenses and less commonly also prisms (dioptrics) * Reflecting telescopes, which use mirrors ( catoptrics) * Catadioptric telescopes, which combine lenses and mirrors An optical telescope's ability to resolve small details is directly related to the diameter (or aperture) of its objective (the primary lens or mirror that collects and focuses the light), and its light-gathering power is related to the area of the objective. The larger the objective, the more light the telescope collects and the finer detail it resolves. People use optical telescopes (including monoculars and binoculars) for outdoor activities such as observation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Largest Optical Reflecting Telescopes
A ''list'' is any set of items in a row. List or lists may also refer to: People * List (surname) Organizations * List College, an undergraduate division of the Jewish Theological Seminary of America * SC Germania List, German rugby union club Other uses * Angle of list, the leaning to either port or starboard of a ship * List (information), an ordered collection of pieces of information ** List (abstract data type), a method to organize data in computer science * List on Sylt, previously called List, the northernmost village in Germany, on the island of Sylt * ''List'', an alternative term for ''roll'' in flight dynamics * To ''list'' a building, etc., in the UK it means to designate it a listed building that may not be altered without permission * Lists (jousting), the barriers used to designate the tournament area where medieval knights jousted * ''The Book of Lists'', an American series of books with unusual lists See also * The List (other) * Listing (di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apache Point Observatory
The Apache Point Observatory (APO; obs. code: 705) is an astronomical observatory located in the Sacramento Mountains in Sunspot, New Mexico, United States, approximately south of Cloudcroft. The observatory is operated by New Mexico State University (NMSU) and owned by the Astrophysical Research Consortium (ARC). Access to the telescopes and buildings is private and restricted. History The ARC was formed in 1984 with the goal of building the 3.5 m telescope. It originally consisted of five institutions: New Mexico State University, University of Washington, University of Chicago, Princeton University, and Washington State University, some of which have since withdrawn. Several additional organizations have joined over time: Johns Hopkins University, University of Colorado, University of Virginia, Georgia State University, University of Oklahoma, University of Wyoming, and Brigham Young University. Funding for the 3.5 m and 0.5 m telescopes comes from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sloan Digital Sky Survey
The Sloan Digital Sky Survey or SDSS is a major multi-spectral imaging and spectroscopic redshift survey using a dedicated 2.5-m wide-angle optical telescope at Apache Point Observatory in New Mexico, United States. The project began in 2000 and was named after the Alfred P. Sloan Foundation, which contributed significant funding. A consortium of the University of Washington and Princeton University was established to conduct a redshift survey. The Astrophysical Research Consortium (ARC) was established in 1984 with the additional participation of New Mexico State University and Washington State University to manage activities at Apache Point. In 1991 the Sloan Foundation granted the ARC funding for survey efforts and the construction of equipment to carry out the work.. Background At the time of its design, the SDSS was a pioneering combination of novel instrumentation as well as data reduction and storage techniques that drove major advances in astronomical observations, di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Pollution
Light pollution is the presence of unwanted, inappropriate, or excessive use of artificial Visible spectrum, lighting. In a descriptive sense, the term ''light pollution'' refers to the effects of any poorly implemented lighting, during the day or night. Light pollution can be understood not only as a phenomenon resulting from a specific source or kind of pollution, but also as a contributor to the wider, collective impact of various sources of pollution. Although this type of pollution can exist throughout the day, its effects are magnified during the night with the contrast of darkness. It has been estimated that 83 percent of the world's people live under light-polluted skies and that 23 percent of the world's land area is affected by skyglow. The area affected by artificial illumination continues to increase. A major side-effect of urbanization, light pollution is blamed for compromising health, disrupting ecosystems, and spoiling aesthetic environments. Globally, it has incr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Pollution
Air pollution is the contamination of air due to the presence of substances in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. There are many different types of air pollutants, such as gases (including ammonia, carbon monoxide, sulfur dioxide, nitrous oxides, methane, carbon dioxide and chlorofluorocarbons), particulates (both organic and inorganic), and biological molecules. Air pollution can cause diseases, allergies, and even death to humans; it can also cause harm to other living organisms such as animals and food crops, and may damage the natural environment (for example, climate change, ozone depletion or habitat degradation) or built environment (for example, acid rain). Air pollution can be caused by both human activities and natural phenomena. Air pollution is a significant risk factor for a number of pollution-related diseases, including respiratory infections, heart disease, COPD ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beijing
} Beijing ( ; ; ), alternatively romanized as Peking ( ), is the capital of the People's Republic of China. It is the center of power and development of the country. Beijing is the world's most populous national capital city, with over 21 million residents. It has an administrative area of , the third in the country after Guangzhou and Shanghai. It is located in Northern China, and is governed as a municipality under the direct administration of the State Council with 16 urban, suburban, and rural districts.Figures based on 2006 statistics published in 2007 National Statistical Yearbook of China and available online at archive. Retrieved 21 April 2009. Beijing is mostly surrounded by Hebei Province with the exception of neighboring Tianjin to the southeast; together, the three divisions form the Jingjinji megalopolis and the national capital region of China. Beijing is a global city and one of the world's leading centres for culture, diplomacy, politics, finance, busi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quasars
A quasar is an extremely luminous active galactic nucleus (AGN). It is pronounced , and sometimes known as a quasi-stellar object, abbreviated QSO. This emission from a galaxy nucleus is powered by a supermassive black hole with a mass ranging from millions to tens of billions of solar masses, surrounded by a gaseous accretion disc. Gas in the disc falling towards the black hole heats up because of friction and releases energy in the form of electromagnetic radiation. The radiant energy of quasars is enormous; the most powerful quasars have luminosities thousands of times greater than that of a galaxy such as the Milky Way. Usually, quasars are categorized as a subclass of the more general category of AGN. The redshifts of quasars are of cosmological origin. The term originated as a contraction of "quasi-stellar '' tar-like' radio source"—because quasars were first identified during the 1950s as sources of radio-wave emission of unknown physical origin—and when identifie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serendipitous
Serendipity is an unplanned fortunate discovery. Serendipity is a common occurrence throughout the history of product invention and scientific discovery. Etymology The first noted use of "serendipity" was by Horace Walpole on 28 January 1754. In a letter he wrote to his friend Horace Mann, Walpole explained an unexpected discovery he had made about a lost painting of Bianca Cappello by Giorgio Vasari by reference to a Persian fairy tale, ''The Three Princes of Serendip''. The princes, he told his correspondent, were "always making discoveries, by accidents and sagacity, of things which they were not in quest of." The name comes from '' Serendip'', an old Persian name for Sri Lanka (Ceylon), hence ''Sarandib'' by Arab traders. It is derived from the Sanskrit ''Siṃhaladvīpaḥ'' (Siṃhalaḥ, Sri Lanka + dvīpaḥ, island). The word has been exported into many other languages, with the general meaning of "unexpected discovery" or "fortunate chance". Applications Inven ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aperture
In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane. An optical system typically has many openings or structures that limit the ray bundles (ray bundles are also known as ''pencils'' of light). These structures may be the edge of a lens or mirror, or a ring or other fixture that holds an optical element in place, or may be a special element such as a diaphragm placed in the optical path to limit the light admitted by the system. In general, these structures are called stops, and the aperture stop is the stop that primarily determines the ray cone angle and brightness at the image point. In some contexts, especially in photography and astronomy, ''aperture'' refers to the diameter of the aperture stop rather than the physical stop or the opening itself. For example, in a telescope, the aperture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
