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Westerlund Telescope
The Westerlund telescope was inaugurated in 2004. and is named after Bengt Westerlund (1921–2008). The telescope belongs to Uppsala Astronomical Observatory and serves as a training telescope. It is used in courses for undergraduates, graduates, and examination projects as well as ordinary astronomical observations by astronomers at the observatory. Site The telescope is situated at the south end on top of the Ångström laboratory, the main physics building of Uppsala University. The building stands on a gravel slope, which is a part of Uppsala esker, next to the Fyris river with a main road just to the south. The central part of Uppsala and the main building is to the northwest to northeast. The horizon is free from northeast to southeast with the Uppsala plain and southeast part of the city. From southeast to south there are pine tree embedded buildings, and from south to northwest there are pine forest in front of the south and southwest part of the city. The sky is unb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bengt Westerlund
Bengt Westerlund (January 17, 1921 - June 4, 2008) was a Swedish astronomer who specialised in observational astronomy. He received his PhD from Uppsala University in 1954. In 1957 he was appointed astronomer at the Uppsala Southern Station at Mount Stromlo Observatory in Australia, where he made extensive studies of the southern Milky Way and the Magellanic Clouds. In 1967 he took a position as astronomer at Steward Observatory in Arizona and in 1969 was appointed Director of ESO in Chile, a position he held until 1975, when he returned to Sweden to become Professor of Astronomy at Uppsala Astronomical Observatory, retiring in 1987. His work on the structure of the Milky Way and the Magellanic Clouds was held in high regard. He contributed significantly in studies of star clusters, stellar populations, carbon stars, planetary nebulae, Wolf-Rayet stars, stellar classification and supernova remnants. He was regarded as an expert on the Magellanic Clouds and wrote a book on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cassegrain Reflector
The Cassegrain reflector is a combination of a primary concave mirror and a secondary convex mirror, often used in optical telescopes and radio antennas, the main characteristic being that the optical path folds back onto itself, relative to the optical system's primary mirror entrance aperture. This design puts the focal point at a convenient location behind the primary mirror and the convex secondary adds a telephoto effect creating a much longer focal length in a mechanically short system. In a symmetrical Cassegrain both mirrors are aligned about the optical axis, and the primary mirror usually contains a hole in the center, thus permitting the light to reach an eyepiece, a camera, or an image sensor. Alternatively, as in many radio telescopes, the final focus may be in front of the primary. In an asymmetrical Cassegrain, the mirror(s) may be tilted to avoid obscuration of the primary or to avoid the need for a hole in the primary mirror (or both). The classic Cassegrain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomy In Sweden
Astronomy () is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, galaxies, and comets. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, astronomy studies everything that originates beyond Earth's atmosphere. Cosmology is a branch of astronomy that studies the universe as a whole. Astronomy is one of the oldest natural sciences. The early civilizations in recorded history made methodical observations of the night sky. These include the Babylonians, Greeks, Indians, Egyptians, Chinese, Maya, and many ancient indigenous peoples of the Americas. In the past, astronomy included disciplines as diverse as astrometry, celestial navigation, observational astronomy, and the making of calendars. Nowadays, p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collimator
A collimator is a device which narrows a beam of particles or waves. To narrow can mean either to cause the directions of motion to become more aligned in a specific direction (i.e., make collimated light or parallel rays), or to cause the spatial cross section of the beam to become smaller (beam limiting device). History The English physicist Henry Kater was the inventor of the floating collimator, which rendered a great service to practical astronomy. He reported about his invention in January 1825. In his report, Kater mentioned previous work in this area by Carl Friedrich Gauss and Friedrich Bessel. Optical collimators In optics, a collimator may consist of a curved mirror or lens A lens is a transmissive optical device which focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements''), ... with some type of light source and/or an im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sweden
Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, Finland to the east, and is connected to Denmark in the southwest by a bridgetunnel across the Öresund. At , Sweden is the largest Nordic country, the third-largest country in the European Union, and the fifth-largest country in Europe. The capital and largest city is Stockholm. Sweden has a total population of 10.5 million, and a low population density of , with around 87% of Swedes residing in urban areas in the central and southern half of the country. Sweden has a nature dominated by forests and a large amount of lakes, including some of the largest in Europe. Many long rivers run from the Scandes range through the landscape, primarily ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stockholm
Stockholm () is the Capital city, capital and List of urban areas in Sweden by population, largest city of Sweden as well as the List of urban areas in the Nordic countries, largest urban area in Scandinavia. Approximately 980,000 people live in the Stockholm Municipality, municipality, with 1.6 million in the Stockholm urban area, urban area, and 2.4 million in the Metropolitan Stockholm, metropolitan area. The city stretches across fourteen islands where Mälaren, Lake Mälaren flows into the Baltic Sea. Outside the city to the east, and along the coast, is the island chain of the Stockholm archipelago. The area has been settled since the Stone Age, in the 6th millennium BC, and was founded as a city in 1252 by Swedish statesman Birger Jarl. It is also the county seat of Stockholm County. For several hundred years, Stockholm was the capital of Finland as well (), which then was a part of Sweden. The population of the municipality of Stockholm is expected to reach o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasmyth Focus
The Nasmyth telescope, also called Nasmyth–Cassegrain or Cassegrain–Nasmyth, is a reflecting telescope developed by the Scottish inventor James Nasmyth. It is a modified form of a Cassegrain telescope, with light reflected sideways to an eyepiece. Scheme As in the Cassegrain telescope, the light falls on a concave primary mirror, then is reflected towards a convex secondary mirror. A comparatively small tertiary flat mirror reflects the light to one of the sides of the telescope. (The central hole in the primary mirror may still host a Cassegrain focus if the tertiary can be moved out of the way.) This flat mirror is placed on the altitude axis, so that the beam exits through a hole in the middle of the altitude bearing. This means the eyepiece or instrument does not need to move up and down with the telescope as the tertiary mirror's angle with the main telescope axis is adjustable as a function of the telescope's pointing and the star's elevation above the horizon; therefor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plane Mirror
A plane mirror is a mirror with a flat (planar) reflective surface. For light rays striking a plane mirror, the angle of reflection equals the angle of incidence. The angle of the incidence is the angle between the incident ray and the surface normal (an imaginary line perpendicular to the surface). Therefore, the angle of reflection is the angle between the reflected ray and the normal and a collimated beam of light does not spread out after reflection from a plane mirror, except for diffraction effects. A plane mirror makes an image of objects in front of the mirror; these images appear to be behind the plane in which the mirror lies. A straight line drawn from part of an object to the corresponding part of its image makes a right angle with, and is bisected by, the surface of the plane mirror. The image formed by a plane mirror is virtual (meaning that the light rays do not actually come from the image) it is not real image (meaning that the light rays do actually come fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arlanda
Stockholm Arlanda Airport is an international airport located in the Sigtuna Municipality of Sweden, near the town of Märsta, north of Stockholm and nearly south-east of Uppsala. The airport is located within Stockholm County and the province of Uppland. It is the largest airport in Sweden and the third-largest airport in the Nordic countries. The airport is the major gateway to international air travel for large parts of Sweden. Arlanda Airport was used by nearly 27 million passengers in 2017, with 21.2 million international passengers and 5.5 million domestic. Stockholm Arlanda Airport is the larger of Stockholm's two airports. The other, Stockholm–Bromma, is located north-west of the city's centre but can be used only by a small number of smaller aircraft. The smaller airports Stockholm-Skavsta and Stockholm-Västerås are both located around away from the Swedish capital. Stockholm Arlanda serves as a major hub for Scandinavian Airlines and Norwegian Air Shuttle. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uppsala Astronomical Observatory
The Uppsala Astronomical Observatory (UAO), Astronomiska observatoriet i Uppsala) is the oldest astronomical observatory in Sweden. It was founded in 1741, though there was a professorial chair of astronomy at the University of Uppsala from 1593 and the university archives include lecture notes in astronomy from the 1480s. In the 18th century, Anders Celsius performed his research there and built the first observatory proper in 1741. Celsius got the university consistory to buy a large stone house of medieval origin in central Uppsala, where he had an observatory constructed on the rooftop. Celsius both worked and had his personal living quarters in the house. This observatory remained in use until the new observatory, now known as the "old observatory", was built in 1853. The Celsius house itself remains as one of few older buildings on a modern shopping street, but the observatory on the roof was demolished in 1857. In the 19th century Anders Jonas Ångström was keeper of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zenith
The zenith (, ) is an imaginary point directly "above" a particular location, on the celestial sphere. "Above" means in the vertical direction (plumb line) opposite to the gravity direction at that location (nadir). The zenith is the "highest" point on the celestial sphere. Origin The word "zenith" derives from an inaccurate reading of the Arabic expression (), meaning "direction of the head" or "path above the head", by Medieval Latin scribes in the Middle Ages (during the 14th century), possibly through Old Spanish. It was reduced to "samt" ("direction") and miswritten as "senit"/"cenit", the "m" being misread as "ni". Through the Old French "cenith", "zenith" first appeared in the 17th century. Relevance and use The term ''zenith'' sometimes means the highest point, way, or level reached by a celestial body on its daily apparent path around a given point of observation. This sense of the word is often used to describe the position of the Sun ("The sun reached its zenit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uppsala
Uppsala (, or all ending in , ; archaically spelled ''Upsala'') is the county seat of Uppsala County and the List of urban areas in Sweden by population, fourth-largest city in Sweden, after Stockholm, Gothenburg, and Malmö. It had 177,074 inhabitants in 2019. Located north of the capital Stockholm it is also the seat of Uppsala Municipality. Since 1164, Uppsala has been the ecclesiology, ecclesiastical centre of Sweden, being the seat of the Archbishop of Uppsala, Archbishop of the Church of Sweden. Uppsala is home to Scandinavia's largest cathedral – Uppsala Cathedral, which was the frequent site of the coronation of the Swedish monarch until the late 19th century. Uppsala Castle, built by King Gustav I of Sweden, Gustav Vasa, served as one of the royal residences of the Swedish monarchs, and was expanded several times over its history, making Uppsala the secondary capital of Sweden during its Swedish Empire, greatest extent. Today it serves as the residence of the Gover ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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