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Antikythera Mechanism
The Antikythera mechanism ( ) is an Ancient Greek hand-powered orrery, described as the oldest example of an analogue computer used to predict astronomical positions and eclipses decades in advance. It could also be used to track the four-year cycle of athletic games which was similar to an Olympiad, the cycle of the ancient Olympic Games. This artefact was among wreckage retrieved from a shipwreck off the coast of the Greek island Antikythera in 1901. On 17 May 1902, it was identified as containing a gear by archaeologist Valerios Stais. The device, housed in the remains of a wooden-framed case of (uncertain) overall size , was found as one lump, later separated into three main fragments which are now divided into 82 separate fragments after conservation efforts. Four of these fragments contain gears, while inscriptions are found on many others. The largest gear is approximately in diameter and originally had 223 teeth. In 2008, a team led by Mike Edmunds and Tony Free ...
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Analogue Computer
An analog computer or analogue computer is a type of computer that uses the continuous variation aspect of physical phenomena such as electrical, mechanical, or hydraulic quantities (''analog signals'') to model the problem being solved. In contrast, digital computers represent varying quantities symbolically and by discrete values of both time and amplitude ( digital signals). Analog computers can have a very wide range of complexity. Slide rules and nomograms are the simplest, while naval gunfire control computers and large hybrid digital/analog computers were among the most complicated. Complex mechanisms for process control and protective relays used analog computation to perform control and protective functions. Analog computers were widely used in scientific and industrial applications even after the advent of digital computers, because at the time they were typically much faster, but they started to become obsolete as early as the 1950s and 1960s, although they rem ...
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Tomography
Tomography is imaging by sections or sectioning that uses any kind of penetrating wave. The method is used in radiology, archaeology, biology, atmospheric science, geophysics, oceanography, plasma physics, materials science, astrophysics, quantum information, and other areas of science. The word ''tomography'' is derived from Ancient Greek τόμος ''tomos'', "slice, section" and γράφω ''graphō'', "to write" or, in this context as well, "to describe." A device used in tomography is called a tomograph, while the image produced is a tomogram. In many cases, the production of these images is based on the mathematical procedure tomographic reconstruction, such as X-ray computed tomography technically being produced from multiple projectional radiographs. Many different reconstruction algorithms exist. Most algorithms fall into one of two categories: filtered back projection (FBP) and iterative reconstruction (IR). These procedures give inexact results: they repres ...
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Giovanni Dondi Dell'Orologio
Giovanni Dondi dell'Orologio (c. 1330 – 1388), also known as Giovanni de' Dondi, was an Italian physician, astronomer and mechanical engineer in Padua, now in Italy. He is remembered today as a pioneer in the art of clock design and construction. The Astrarium, which he designed and built over a period of 16 years, was a highly complex astronomical clock and planetarium, constructed only 60 or so years after the very first all-mechanical clocks had been built in Europe, and demonstrated an ambitious attempt to describe and model the planetary system with mathematical precision and technological sophistication. Life Giovanni was the second son of Jacopo Dondi dell'Orologio and Zaccarota Centrago or Centraco of Chioggia. His father was a doctor and astronomer, and builder of a large astronomical clock in the tower of the Palazzo Capitaniato of Padua in 1344. Giovanni lived with his father from 1348 to 1359, and shared his father's interest in astronomy and clockmaking. In 13 ...
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Richard Of Wallingford
Richard of Wallingford (1292–1336) was an English mathematician, astronomer, horologist, and cleric who made major contributions to astronomy and horology while serving as abbot of St Albans Abbey in Hertfordshire. Biography Richard was born, the son of a blacksmith, at Wallingford in Berkshire (now Oxfordshire) in England in 1292. When he was orphaned he was taken to William de Kirkeby the Prior of Wallingford Priory and dedicated to the Holy Trinity. (Wallingford was a dependant priory to S Albans Abbey) Richard subsequently spent six years studying at Oxford University before becoming a monk at St Albans. He later studied for nine more years at Oxford. In 1327 he became abbot of St Albans. Richard of Wallingford is best known for the astronomical clock he designed, while he was abbot, which is described in the ''Tractatus Horologii Astronomici'' (1327). The clock was completed about 20 years after Richard's death by William of Walsham but was apparently destroyed during ...
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Astronomical Clock
An astronomical clock, horologium, or orloj is a clock with special mechanisms and dials to display astronomical information, such as the relative positions of the Sun, Moon, zodiacal constellations, and sometimes major planets. Definition The term is loosely used to refer to any clock that shows, in addition to the time of day, astronomical information. This could include the location of the Sun and Moon in the sky, the age and Lunar phases, the position of the Sun on the ecliptic and the current zodiac sign, the sidereal time, and other astronomical data such as the Moon's nodes (for indicating eclipses) or a rotating star map. The term should not be confused with ''astronomical regulator'', a high precision but otherwise ordinary pendulum clock used in observatories. Astronomical clocks usually represent the Solar System using the geocentric model. The center of the dial is often marked with a disc or sphere representing the Earth, located at the center of the Solar ...
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Arxiv
arXiv (pronounced "archive"—the X represents the Greek letter chi ⟨χ⟩) is an open-access repository of electronic preprints and postprints (known as e-prints) approved for posting after moderation, but not peer review. It consists of scientific papers in the fields of mathematics, physics, astronomy, electrical engineering, computer science, quantitative biology, statistics, mathematical finance and economics, which can be accessed online. In many fields of mathematics and physics, almost all scientific papers are self-archived on the arXiv repository before publication in a peer-reviewed journal. Some publishers also grant permission for authors to archive the peer-reviewed postprint. Begun on August 14, 1991, arXiv.org passed the half-million-article milestone on October 3, 2008, and had hit a million by the end of 2014. As of April 2021, the submission rate is about 16,000 articles per month. History arXiv was made possible by the compact TeX file forma ...
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Ars Technica
''Ars Technica'' is a website covering news and opinions in technology, science, politics, and society, created by Ken Fisher and Jon Stokes in 1998. It publishes news, reviews, and guides on issues such as computer hardware and software, science, technology policy, and video games. ''Ars Technica'' was privately owned until May 2008, when it was sold to Condé Nast Digital, the online division of Condé Nast Publications. Condé Nast purchased the site, along with two others, for $25 million and added it to the company's ''Wired'' Digital group, which also includes '' Wired'' and, formerly, Reddit. The staff mostly works from home and has offices in Boston, Chicago, London, New York City, and San Francisco. The operations of ''Ars Technica'' are funded primarily by advertising, and it has offered a paid subscription service since 2001. History Ken Fisher, who serves as the website's current editor-in-chief, and Jon Stokes created ''Ars Technica'' in 1998. Its purpose ...
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The New York Times
''The New York Times'' (''the Times'', ''NYT'', or the Gray Lady) is a daily newspaper based in New York City with a worldwide readership reported in 2020 to comprise a declining 840,000 paid print subscribers, and a growing 6 million paid digital subscribers. It also is a producer of popular podcasts such as '' The Daily''. Founded in 1851 by Henry Jarvis Raymond and George Jones, it was initially published by Raymond, Jones & Company. The ''Times'' has won 132 Pulitzer Prizes, the most of any newspaper, and has long been regarded as a national " newspaper of record". For print it is ranked 18th in the world by circulation and 3rd in the U.S. The paper is owned by the New York Times Company, which is publicly traded. It has been governed by the Sulzberger family since 1896, through a dual-class share structure after its shares became publicly traded. A. G. Sulzberger, the paper's publisher and the company's chairman, is the fifth generation of the family to head the ...
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Science In Classical Antiquity
Science in classical antiquity encompasses inquiries into the workings of the world or universe aimed at both practical goals (e.g., establishing a reliable calendar or determining how to cure a variety of illnesses) as well as more abstract investigations belonging to natural philosophy. Classical antiquity is traditionally defined as the period between 8th century BC and the 6th century AD, and the ideas regarding nature that were theorized during this period were not limited to science but included myths as well as religion. Those who are now considered as the first scientists may have thought of themselves as natural philosophers, as practitioners of a skilled profession (e.g., physicians), or as followers of a religious tradition (e.g., temple healers). Some of the more widely known figures active in this period include Hippocrates, Aristotle, Euclid, Archimedes, Hipparchus, Galen, and Ptolemy. Their contributions and commentaries spread throughout the Eastern, Islamic, and L ...
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Classical Planet
In classical antiquity, the seven classical planets or seven luminaries are the seven moving astronomical objects in the sky visible to the naked eye: the Moon, Mercury, Venus, the Sun, Mars, Jupiter, and Saturn. The word '' planet'' comes from two related Greek words, πλάνης ''planēs'' (whence πλάνητες ἀστέρες ''planētes asteres'' "wandering stars, planets") and πλανήτης ''planētēs'', both with the original meaning of "wanderer", expressing the fact that these objects move across the celestial sphere relative to the fixed stars. Greek astronomers such as Geminus and Ptolemy often divided the seven planets into the Sun, the Moon, and the five planets. The term ''planet'' in modern terminology is only applied to natural satellites directly orbiting the Sun (or other stars), so that only five of the seven classical planets are planets in the modern sense. The same seven planets, along with the ascending and descending lunar node, ar ...
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Rhodes
Rhodes (; el, Ρόδος , translit=Ródos ) is the largest and the historical capital of the Dodecanese islands of Greece. Administratively, the island forms a separate municipality within the Rhodes regional unit, which is part of the South Aegean administrative region. The principal town of the island and seat of the municipality is Rhodes. The city of Rhodes had 50,636 inhabitants in 2011. In 2022 the island has population of 124,851 people. It is located northeast of Crete, southeast of Athens. Rhodes has several nicknames, such as "Island of the Sun" due to its patron sun god Helios, "The Pearl Island", and "The Island of the Knights", named after the Knights of Saint John of Jerusalem, who ruled the island from 1310 to 1522. Historically, Rhodes was famous for the Colossus of Rhodes, one of the Seven Wonders of the Ancient World. The Medieval Old Town of the City of Rhodes has been declared a World Heritage Site. Today, it is one of the most popular tourist desti ...
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Hipparchus
Hipparchus (; el, Ἵππαρχος, ''Hipparkhos'';  BC) was a Greek astronomer, geographer, and mathematician. He is considered the founder of trigonometry, but is most famous for his incidental discovery of the precession of the equinoxes. Hipparchus was born in Nicaea, Bithynia, and probably died on the island of Rhodes, Greece. He is known to have been a working astronomer between 162 and 127 BC. Hipparchus is considered the greatest ancient astronomical observer and, by some, the greatest overall astronomer of antiquity. He was the first whose quantitative and accurate models for the motion of the Sun and Moon survive. For this he certainly made use of the observations and perhaps the mathematical techniques accumulated over centuries by the Babylonians and by Meton of Athens (fifth century BC), Timocharis, Aristyllus, Aristarchus of Samos, and Eratosthenes, among others. He developed trigonometry and constructed trigonometric tables, and he solved ...
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