Great Paris Exhibition Telescope Of 1900
The Great Paris Exhibition Telescope of 1900, with an objective lens of in diameter, was the largest refracting telescope ever constructed. It was built as the centerpiece of the Paris Universal Exhibition of 1900. Its construction was instigated in 1892 by François Deloncle (1856–1922), a member of the French Chambre des Députés. Since it was built for exhibit purposes within a large metropolis, and its design made it difficult to aim at astronomical objects, it was not suited for scientific use. When the year-long exposition was over, its builders were unable to sell it. It was ultimately broken up for scrap; the lenses are still stored away at the Paris Observatory. Design The telescope had two interchangeable objective lenses (for visual and photographic use respectively) in diameter, with a focal length of . Due to its extremely large size, the telescope was mounted in a fixed horizontal position. Light from astronomical objects was redirected into the optical ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Objective (optics)
In optical engineering, an objective is an optical element that gathers light from an object being observed and Focus (optics), focuses the ray (optics), light rays from it to produce a real image of the object. Objectives can be a single Lens (optics), lens or mirror, or combinations of several optical elements. They are used in microscopes, binoculars, telescopes, cameras, slide projectors, CD players and many other optical instruments. Objectives are also called object lenses, object glasses, or objective glasses. Microscope objectives The objective lens of a microscope is the one at the bottom near the sample. At its simplest, it is a very high-powered magnifying glass, with very short focal length. This is brought very close to the specimen being examined so that the light from the specimen comes to a focus inside the microscope tube. The objective itself is usually a cylinder containing one or more lenses that are typically made of glass; its function is to collect light fr ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Eiffel Tower
The Eiffel Tower ( ; ) is a wrought-iron lattice tower on the Champ de Mars in Paris, France. It is named after the engineer Gustave Eiffel, whose company designed and built the tower from 1887 to 1889. Locally nicknamed "''La dame de fer''" (French for "Iron Lady"), it was constructed as the centrepiece of the Exposition Universelle (1889), 1889 World's Fair, and to crown the centennial anniversary of the French Revolution. Although initially criticised by some of France's leading artists and intellectuals for its design, it has since become a global cultural icon of France and one of the most recognisable structures in the world. The tower received 5,889,000 visitors in 2022. The Eiffel Tower is the most visited monument with an entrance fee in the world: 6.91 million people ascended it in 2015. It was designated a in 1964, and was named part of a UNESCO World Heritage Site ("Paris, Banks of the Seine") in 1991. The tower is tall, about the same height as an 81- ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
1900 In Paris
Nineteen or 19 may refer to: * 19 (number) * One of the years 19 BC, AD 19, 1919, 2019 Films * ''19'' (film), a 2001 Japanese film * ''Nineteen'' (1987 film), a 1987 science fiction film * ''19-Nineteen'', a 2009 South Korean film * ''Diciannove'', a 2024 Italian drama film informally referred to as "Nineteen" in some sources Science * Potassium, an alkali metal * 19 Fortuna, an asteroid Music * 19 (band), a Japanese pop music duo Albums * ''19'' (Adele album), 2008 * ''19'', a 2003 album by Alsou * ''19'', a 2006 album by Evan Yo * ''19'', a 2018 album by MHD * ''19'', one half of the double album ''63/19'' by Kool A.D. * ''Number Nineteen'', a 1971 album by American jazz pianist Mal Waldron * ''XIX'' (EP), a 2019 EP by 1the9 Songs * "19" (song), a 1985 song by British musician Paul Hardcastle * "Stone in Focus", officially "#19", a composition by Aphex Twin * "Nineteen", a song from the 1992 album ''Refugee'' by Bad4Good * "Nineteen", a song from the 2001 al ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
1900 In France
Events from the year 1900 in France. Incumbents *President: Émile Loubet *President of the Council of Ministers: Pierre Waldeck-Rousseau Events * The first '' Guide Michelin'' is published for motorists in France. * 31 March – The length of a workday for women and children is limited to 11 hours by law. * 1 April – Every French policeman is assigned to carry a gun. * 14 April–12 November – Exposition Universelle, a world's fair, is staged in Paris. * 21 April – Battle of Kousséri: French troops decisively defeat forces of the Kanem–Bornu Empire in Chad (although the commanders on both sides are killed), achieving the objective of linking all French possessions in Western Africa. * 27 June – Treaty of Paris is signed between the Spanish Empire and the French Empire by which Río Muni is relieved of all conflicting claims. * 19 July – The first line of the Paris Métro is inaugurated. Arts and literature * 2 February – First performance of Gustave Charpen ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
List Of Largest Optical Telescopes Historically
Telescopes have grown in size since they first appeared around 1608. The following tables list the increase in size over the years. Different technologies can and have been used to build telescopes, which are used to magnify distant views and gather light (especially important in astronomy). By overall aperture The following is a list of largest single mount optical telescope An optical telescope gathers and focus (optics), focuses light mainly from the visible spectrum, visible part of the electromagnetic spectrum, to create a magnification, magnified image for direct visual inspection, to make a photograph, or to co ...s sorted by total objective diameter (''aperture''), including segmented and multi-mirror configurations. It is a historical list, with the instruments listed in chronological succession by objective size. By itself, the diameter of the primary optics can be a poor measure of a telescope's historical or scientific significance; for example, William Parsons ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
List Of Largest Optical Refracting Telescopes
Refracting telescopes use a lens to focus light. The Swedish 1-m Solar Telescope, with a lens diameter of 43 inches, is technically the largest, with 39 inches clear for the aperture.The second largest refracting telescope in the world is the Yerkes Observatory 40 inch (102 cm) refractor, used for astronomical and scientific observation for over a century. The next largest refractor telescopes are the James Lick telescope, and the Meudon Great Refractor. Most are classical great refractors, which used achromatic doublets on an equatorial mount. However, other large refractors include a 21st-century solar telescope which is not directly comparable because it uses a single element non-achromatic lens, and the short-lived Great Paris Exhibition Telescope of 1900. It used a 78-inch (200 cm) Focault siderostat for aiming light into the Image-forming optical system part of the telescope, which had a 125 cm diameter lens. Using a siderostat incurs a reflectiv ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Light Pollution
Light pollution is the presence of any unwanted, inappropriate, or excessive artificial Visible spectrum, lighting. In a descriptive sense, the term ''light pollution'' refers to the effects of any poorly implemented lighting sources, 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 the sky's darkness. It has been estimated that 83% of the world's people live under light-polluted skies and that 23% 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. Studies show that ur ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Great Ex Telescope Cartoon
Great may refer to: Descriptions or measurements * Great, a relative measurement in physical space, see Size * Greatness, being divine, majestic, superior, majestic, or transcendent People * List of people known as "the Great" * Artel Great (born 1981), American actor * Great Osobor (born 2002), Spanish-born British basketball player Other uses * ''Great'' (1975 film), a British animated short about Isambard Kingdom Brunel * ''Great'' (2013 film), a German short film * Great (supermarket), a supermarket in Hong Kong * GReAT, Graph Rewriting and Transformation, a Model Transformation Language * Gang Resistance Education and Training, or GREAT, a school-based and police officer-instructed program * Global Research and Analysis Team (GReAT), a cybersecurity team at Kaspersky Lab *'' Great!'', a 2018 EP by Momoland *Great! TV, British TV channel group * ''The Great'' (TV series), an American comedy-drama See also * * * * * The Great (other) The Great is the moniker ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Strand Magazine
''The Strand Magazine'' was a monthly British magazine founded by George Newnes, composed of short fiction and general interest articles. It was published in the United Kingdom from January 1891 to March 1950, running to 711 issues, though the first issue was on sale well before Christmas 1890. Its immediate popularity is evidenced by an initial sale of nearly 300,000. Sales increased in the early months, before settling down to a circulation of almost 500,000 copies a month, which lasted well into the 1930s. It was edited by Herbert Greenhough Smith from 1891 to 1930. The popularity of Sherlock Holmes became widespread after first appearing in the magazine in 1891. The magazine's original offices were on Burleigh Street off The Strand, London. It was revived in 1998 as a quarterly magazine. Publication history ''The Strand Magazine'' was founded by George Newnes in 1890, and its first edition was dated January 1891. The magazine's original offices were located on Burleigh ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Moon
The Moon is Earth's only natural satellite. It Orbit of the Moon, orbits around Earth at Lunar distance, an average distance of (; about 30 times Earth diameter, Earth's diameter). The Moon rotation, rotates, with a rotation period (lunar day) that is synchronized to its orbital period (Lunar month#Synodic month, lunar month) of 29.5 Earth days. This is the product of Earth's gravitation having tidal forces, tidally pulled on the Moon until one part of it stopped rotating away from the near side of the Moon, near side, making always the same lunar surface face Earth. Conversley, the gravitational pull of the Moon, on Earth, is the main driver of Earth's tides. In geophysical definition of planet, geophysical terms, the Moon is a planetary-mass object or satellite planet. Its mass is 1.2% that of the Earth, and its diameter is , roughly one-quarter of Earth's (about as wide as the contiguous United States). Within the Solar System, it is the List of Solar System objects by ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Nebula
A nebula (; or nebulas) is a distinct luminescent part of interstellar medium, which can consist of ionized, neutral, or molecular hydrogen and also cosmic dust. Nebulae are often star-forming regions, such as in the Pillars of Creation in the Eagle Nebula. In these regions, the formations of gas, dust, and other materials "clump" together to form denser regions, which attract further matter and eventually become dense enough to form stars. The remaining material is then thought to form planets and other planetary system objects. Most nebulae are of vast size; some are hundreds of light-years in diameter. A nebula that is visible to the human eye from Earth would appear larger, but no brighter, from close by. The Orion Nebula, the brightest nebula in the sky and occupying an area twice the angular diameter of the full Moon, can be viewed with the naked eye but was missed by early astronomers. Although denser than the space surrounding them, most nebulae are far less dens ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Eugène Michel Antoniadi
Eugène Michel Antoniadi (Greek: Ευγένιος Αντωνιάδης; 1 March 1870 – 10 February 1944) was a Greek-French astronomer. He is known for creating the Antoniadi scale as well as for his observations of the planets, and was a major opponent of the notion of Martian canals. He created some very detailed maps of Mars and many features on the planet are still known by the names he suggested. He also created the first map of Mercury, though it turned out to be incorrect. Biography Antoniadi was born in Istanbul (Constantinople) but spent most of his adult life in France after being invited there by Camille Flammarion. He became a Fellow of the Royal Astronomical Society on 10 February 1899, and in 1890 he became one of the founding members of the British Astronomical Association (BAA). In 1892, he joined the BAA's Mars Section and became that section's Director in 1896. He became a member of the Société astronomique de France (SAF) in 1891. Flammarion hire ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |