Paris 1900 exposition refractor.

Here is a list of the largest optical refracting telescopes sorted by lens diameter and focal length. Paris 1900 refractor. ... Paris 1900 refractor. ... Image of a refracting telescope from the Cincinnati Observatory in 1848 A refracting or refractor telescope is a dioptric telescope that uses a lens as its objective to form an image. ...

The largest refractor ever constructed was French: an instrument sporting two interchangeable objective lenses (for visual and photographic use respectively) 1.25 m (49.2 inches) in diameter, with a focal length of 57 m (187 ft). It was on display at the 1905 Paris Exposition. Due to the extreme focal length it was stationary. The telescope was aimed with the aid of a Foucault siderostat, a movable plane mirror 2 m (6.56 feet) in diameter, mounted in a large cast-iron frame. The horizontal steel tube was 60 m (197 feet) long; for focusing, the telescope’s eyepiece/plate end could be shifted five feet on rails. With the lowest power—500x—the field of view was 3 arc minutes. Due to its unfortunate location—right within the metropolis—and trouble with the siderostat, the results were poor and 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. An objective lens is the lens in a microscope, telescope, camera or other optical instrument, that receives the first light rays from the object being observed. ... The focal point F and focal length f of a positive (convex) lens, a negative (concave) lens, a concave mirror, and a convex mirror. ... ... A Heliostat is a device that tracks the movement of the sun. ... gros pd]], enfoire at Nançay. ...

The focal point F and focal length f of a positive (convex) lens, a negative (concave) lens, a concave mirror, and a convex mirror. ... The Exposition Universelle of 1900 was a worlds fair held in Paris, France, to celebrate the achivements of the past century and to accelerate development into the next. ... City flag City coat of arms Motto: Fluctuat nec mergitur (Latin: Tossed by the waves, she does not sink) The Eiffel Tower in Paris, as seen from the esplanade du Trocadéro. ... Year 1900 (MCM) was an exceptional common year starting on Monday (link will display the full calendar) of the Gregorian calendar, but a leap year starting on Saturday of the Julian calendar. ... 1897 photo of the 102 cm (40 inch) refractor at the Yerkes Observatory. ... Williams Bay is a village located in Walworth County, Wisconsin. ... 1897 (MDCCCXCVII) was a common year starting on Friday (see link for calendar). ... The Swedish Solar Telescope (or SST) is a 1m telescope on La Palma in the Canary Islands. ... The seeing statistics for Roque de los Muchachos Observatory make it the third best location for optical and infrared astronomy after Dome C, Antarctica and Mauna Kea Observatory, Hawaii. ... Satellite image of La Palma, with the Caldera de Taburiente visible (north is to the lower right). ... For album titles with the same name, see 2002 (album). ... A deformable mirror can be used to correct wavefront errors in an astronomical telescope. ... The Lick Observatory is an astronomical observatory, owned and operated by the University of California. ... Mount Hamilton is a mountain in Californias Diablo Range. ... Year 1888 (MDCCCLXXXVIII) was a leap year starting on Sunday (click on link for calendar) of the Gregorian calendar (or a leap year starting on Tuesday of the 12-day slower Julian calendar). ... gros pd]], enfoire at Nançay. ... Meudon is a suburb of Paris in the department of Hauts-de-Seine in northern France. ... Year 1891 (MDCCCXCI) was a common year starting on Thursday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Saturday of the 12-day slower Julian calendar). ... Potsdam is the capital city of the federal state of Brandenburg in Germany. ... Year 1899 (MDCCCXCIX) was a common year starting on Sunday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Friday [1] of the 12-day-slower Julian calendar). ... The Côte dAzur Observatory (in French: Observatoire de la Côte dAzur) originated in 1988 with the merger of two observatories: Nice Observatory The CERGA (Centre dÉtudes et de Recherches Géodynamiques et Astronomiques) External links Côte dAzur Observatory official website (English version) ... Night view along the Promenade des Anglais This article is about the city. ... 1887 (MDCCCLXXXVII) is a common year starting on Saturday (click on link for calendar) of the Gregorian calendar or a common year starting on Monday of the Julian calendar. ... The Allegheny Observatory was founded on February 15, 1859 in the city of Allegheny, Pennsylvania. ... Nickname: Motto: Benigno Numine (With the Benevolent Deity) Location in Allegheny County, Pennsylvania Coordinates: , Country United States Commonwealth Pennsylvania County Allegheny Founded November 25, 1758 Incorporated April 22, 1794 (borough)   March 18, 1816 (city) Government  - Mayor Luke Ravenstahl (D) Area  - City 151. ... Year 1914 (MCMXIV) was a common year starting on Thursday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Wednesday of the 13-day-slower Julian calendar). ... Royal Observatory, Greenwich The original site of the Royal Greenwich Observatory (RGO), which was built as a workplace for the Astronomer Royal, was on a hill in Greenwich Park in Greenwich, London, overlooking the River Thames. ... This page is about Greenwich in England. ... 1894 (MDCCCXCIV) was a common year starting on Monday (see link for calendar). ... Vienna University Observatory Vienna Observatory is an astronomical observatory in Vienna, Austria. ... This article is about the city and federal state in Austria. ... 1878 (MDCCCLXXVIII) was a common year starting on Tuesday (see link for calendar). ... This article does not cite any references or sources. ... For other uses, see Berlin (disambiguation). ... Year 1896 (MDCCCXCVI) was a leap year starting on Wednesday (link will display calendar). ... Leander McCormick Observatory in 1890 The McCormick Observatory is one of the astronomical observatories operated by the Astronomy Department of the University of Virginia and is situated in Charlottesville, Virginia (USA). ... Nickname: C-Ville Location in the Commonwealth of Virginia Coordinates: Country United States State Virginia County Albemarle County Founded 1762  - Mayor David E. Brown Area    - City 26. ... 1883 (MDCCCLXXXIII) was a common year starting on Monday (see link for calendar). ... Aerial view of USNO. The United States Naval Observatory (USNO) is one of the oldest scientific agencies in the United States. ... Aerial photo (looking NW) of the Washington Monument and the White House in Washington, DC. Washington, D.C., officially the District of Columbia (also known as D.C.; Washington; the Nations Capital; the District; and, historically, the Federal City) is the capital city and administrative district of the United... 1873 (MDCCCLXXIII) was a common year starting on Wednesday (see link for calendar). ... Royal Observatory, Greenwich The original site of the Royal Greenwich Observatory (RGO), which was built as a workplace for the Astronomer Royal, was on a hill in Greenwich Park in Greenwich, London, overlooking the River Thames. ... This page is about Greenwich in England. ... 1897 (MDCCCXCVII) was a common year starting on Friday (see link for calendar). ... Johannesburgs skyline as seen from the observation deck of the Carlton Centre. ... Year 1925 (MCMXXV) was a common year starting on Thursday (link will display the full calendar) of the Gregorian calendar. ... The old administration building with the dome of the Farnham telescope The dome of the 50-inch Great Melbourne telescope Mount Stromlo Observatory (MSO) located just outside of Canberra, Australia, is part of the Research School of Astronomy and Astrophysics at the Australian National University (ANU). ... 1952 (MCMLII) was a Leap year starting on Tuesday (link will take you to calendar). ... The old administration building with the dome of the Farnham telescope The dome of the 50-inch Great Melbourne telescope Mount Stromlo Observatory (MSO) located just outside of Canberra, Australia, is part of the Research School of Astronomy and Astrophysics at the Australian National University (ANU). ... Mount Stromlo Locality Map Mount Stromlo is situated a short drive west of the centre of Canberra, Australia, near the district of Weston Creek. ... Year 1925 (MCMXXV) was a common year starting on Thursday (link will display the full calendar) of the Gregorian calendar. ... 2003 Canberra bushfires The Canberra bushfires of 2003 caused severe damage to the outskirts of Canberra, the Australian capital city. ... is the 18th day of the year in the Gregorian calendar. ... 2003 (MMIII) was a common year starting on Wednesday of the Gregorian calendar. ... For other uses, see Belgrade (disambiguation). ... The Berlin Observatory has its origins in 1700 when Gottfried Leibniz initiated the Brandenburgische Society which would later become Prussian Academy of Sciences. ... The Berlin Observatory has its origins in 1700 when Gottfried Leibniz initiated the Brandenburgische Society which would later become Prussian Academy of Sciences. ... Potsdam is the capital city of the federal state of Brandenburg in Germany. ... Year 1914 (MCMXIV) was a common year starting on Thursday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Wednesday of the 13-day-slower Julian calendar). ... The Berlin Observatory has its origins in 1700 when Gottfried Leibniz initiated the Brandenburgische Society which would later become Prussian Academy of Sciences. ... Year 1913 (MCMXIII) was a common year starting on Wednesday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Tuesday of the 13-day-slower Julian calendar). ... Castle of Babelsberg with the river Havel as one part of the UNESCO World Heritage Site Observatory on the Babelsberg UEFA Womens Cup final Potsdam-Babelsberg or short Babelsberg is the largest district of the city of Potsdam, Germany today. ...

See also

• List of largest optical reflecting telescopes