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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 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 even the larg ...
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SOFIA 2
Sofia ( ; bg, София, Sofiya, ) is the Capital city, capital and List of cities and towns in Bulgaria, largest city of Bulgaria. It is situated in the Sofia Valley at the foot of the Vitosha mountain in the western parts of the country. The city is built west of the Iskar (river), Iskar river, and has many mineral springs, such as the Sofia Central Mineral Baths. It has a humid continental climate. Being in the centre of the Balkans, it is midway between the Black Sea and the Adriatic Sea, and closest to the Aegean Sea. Known as Serdica in Late antiquity, Antiquity and Sredets in the Middle Ages, Sofia has been an area of List of oldest continuously inhabited cities, human habitation since at least 7000 BC. The recorded history of the city begins with the attestation of the conquest of Serdica by the Roman Republic in 29 BC from the Celtic settlement of Southeast Europe, Celtic tribe Serdi. During the decline of the Roman Empire, the city was raided by Huns, Visigoths, P ...
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Hubble Space Telescope
The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most versatile, renowned both as a vital research tool and as a public relations boon for astronomy. The Hubble telescope is named after astronomer Edwin Hubble and is one of NASA's Great Observatories. The Space Telescope Science Institute (STScI) selects Hubble's targets and processes the resulting data, while the Goddard Space Flight Center (GSFC) controls the spacecraft. Hubble features a mirror, and its five main instruments observe in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum. Hubble's orbit outside the distortion of Earth's atmosphere allows it to capture extremely high-resolution images with substantially lower background light than ground-based telescopes. It has recorded some of the most detaile ...
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Parabolic Reflector
A parabolic (or paraboloid or paraboloidal) reflector (or dish or mirror) is a reflective surface used to collect or project energy such as light, sound, or radio waves. Its shape is part of a circular paraboloid, that is, the surface generated by a parabola revolving around its axis. The parabolic reflector transforms an incoming plane wave travelling along the axis into a spherical wave converging toward the focus. Conversely, a spherical wave generated by a point source placed in the focus is reflected into a plane wave propagating as a collimated beam along the axis. Parabolic reflectors are used to collect energy from a distant source (for example sound waves or incoming star light). Since the principles of reflection are reversible, parabolic reflectors can also be used to collimate radiation from an isotropic source into a parallel beam. In optics, parabolic mirrors are used to gather light in reflecting telescopes and solar furnaces, and project a beam of light in flas ...
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Niccolò Zucchi
Niccolò Zucchi (; December 6, 1586 – May 21, 1670) was an Italian Jesuit, astronomer, and physicist. As an astronomer he may have been the first to see the belts on the planet Jupiter (on May 17, 1630), and reported spots on Mars in 1640. His "''Optica philosophia experimentis et ratione a fundamentis constituta''", published in 1652–56, described his 1616 experiments using a curved mirror instead of a lens as a telescope objective, which may be the earliest known description of a reflecting telescope. In his book he also demonstrated that phosphors generate rather than store light. He also published two other works on mechanics and machines. Biography Niccolò Zucchi was fourth of eight children born into the noble family of Pierre Zucchi and Francoise Giande Marie. Three of his sisters became nuns, three of his brothers became Jesuits, and one brother became a secular priest. The Jesuit order Niccolò studied rhetoric in Piacenza and philosophy and theology in Parma. He ...
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Cesare Caravaggi
Cesare, the Italian version of the given name Caesar, may refer to: Given name * Cesare, Marquis of Beccaria (1738–1794), an Italian philosopher and politician * Cesare Airaghi (1840–1896), Italian colonel * Cesare Arzelà (1847–1912), Italian mathematician * Cesare Battisti (other) * Cesare Bocci (born 1957), Italian actor known for the ''Inspector Montalbano'' TV series * Cesare Bonizzi, Franciscan friar and heavy metal singer * Cesare Borgia (1475–1507), Italian general and statesman * Cesare "Cece" Carlucci (1917–2008), American baseball umpire * Cesare Emiliani (1922–1995), Italian-American scientist * Cesare Fiorio (born 1939), Italian sportsperson * Cesare Gianturco (1905–1995), Italian-American physician * Cesare Nava (1861–1933), Italian engineer and politician * Cesare Negri, the late Renaissance dancing-master * Cesare Pavese (1908–1950), Italian poet and novelist * Cesare Romiti (1923–2020), Italian economist and bu ...
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Bologna
Bologna (, , ; egl, label= Emilian, Bulåggna ; lat, Bononia) is the capital and largest city of the Emilia-Romagna region in Northern Italy. It is the seventh most populous city in Italy with about 400,000 inhabitants and 150 different nationalities. Its metropolitan area is home to more than 1,000,000 people. It is known as the Fat City for its rich cuisine, and the Red City for its Spanish-style red tiled rooftops and, more recently, its leftist politics. It is also called the Learned City because it is home to the oldest university in the world. Originally Etruscan, the city has been an important urban center for centuries, first under the Etruscans (who called it ''Felsina''), then under the Celts as ''Bona'', later under the Romans (''Bonōnia''), then again in the Middle Ages, as a free municipality and later ''signoria'', when it was among the largest European cities by population. Famous for its towers, churches and lengthy porticoes, Bologna has a well-preserved ...
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