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Dawn (SF Novel)
''Dawn'' is a science fiction novel by American writer Dean McLaughlin. A re-imagining of Isaac Asimov's 1941 short story " Nightfall", it was serialized in ''Analog'' magazine (April – July 1981), with two cover illustrations, for both its first and last segments. The story was republished in hardcover in 2006. Plot Dawn takes place on a nameless planet in a multiple-star system with six or seven stars, which are regarded as gods by the planet's inhabitants. The planet orbits around Alpher, a yellow star similar to Earth's sun, which forms a binary system with the smaller, cooler Bethe. The other four stars, Gamow, Dalton, Ephron, and Zwicky, are much farther away from Alpher and positioned in such a way that there is always at least one sun visible in the sky. The seventh "god" is the Pale One, which is either a large moon or a double planet. The orbits of the moon and stars are inclined enough that eclipses and occultations are rare events on the planet. Since there is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dean McLaughlin (writer)
Dean Benjamin McLaughlin, Jr. (born 1931) is an American science fiction writer. He was the son of astronomers Dean B. McLaughlin and Laura Elizabeth Hill Mclaughlin. His best-known work is " Hawk Among the Sparrows" (1968), which was nominated for both the Hugo Award and Nebula Award for Best Novella. It concerns a late-20th century fighter plane which travels through time, and tries to contend with World War I aircraft. Other works include ''Dawn'' (1980), a novel inspired by Isaac Asimov's " Nightfall". He has a novella, "Tenbrook of Mars," in the July/August 2008 issue of ''Analog Analog or analogue may refer to: Computing and electronics * Analog signal, in which information is encoded in a continuous variable ** Analog device, an apparatus that operates on analog signals *** Analog electronics, circuits which use analog ...''. References * 1931 births Living people 20th-century American novelists American male novelists American science fiction writers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hourglass
An hourglass (or sandglass, sand timer, sand clock or egg timer) is a device used to measure the passage of time. It comprises two glass bulbs connected vertically by a narrow neck that allows a regulated flow of a substance (historically sand) from the upper bulb to the lower one. Typically, the upper and lower bulbs are symmetric so that the hourglass will measure the same duration regardless of orientation. The specific duration of time a given hourglass measures is determined by factors including the quantity and coarseness of the particulate matter, the bulb size, and the neck width. Depictions of an hourglass as a symbol of the passage of time are found in art, especially on tombstones or other monuments, from antiquity to the present day. The form of a winged hourglass has been used as a literal depiction of the well-known idiom "time flies". History Antiquity The origin of the hourglass is unclear. Its predecessor the clepsydra, or water clock, is known to have exi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fritz Zwicky
Fritz Zwicky (; ; February 14, 1898 – February 8, 1974) was a Swiss astronomer. He worked most of his life at the California Institute of Technology in the United States of America, where he made many important contributions in theoretical and observational astronomy. In 1933, Zwicky was the first to use the virial theorem to infer the existence of unseen dark matter, describing it as "'". From p 125: ''"Um, wie beobachtet, einen mittleren Dopplereffekt von 1000 km/sek oder mehr zu erhalten, müsste also die mittlere Dichte im Comasystem mindestens 400 mal grösser sein als die auf Grund von Beobachtungen an leuchtender Materie abgeleitete. Falls sich dies bewahrheiten sollte, würde sich also das überraschende Resultat ergeben, dass dunkle Materie in sehr viel grösserer Dichte vorhanden ist als leuchtende Materie."'' (In order to obtain an average Doppler effect of 1000 km/s or more, as observed, the average density in the Coma system would thus have to be at least 400 time ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Dalton
John Dalton (; 5 or 6 September 1766 – 27 July 1844) was an English chemist, physicist and meteorologist. He is best known for introducing the atomic theory into chemistry, and for his research into colour blindness, which he had. Colour blindness is known as ''Daltonism'' in several languages, being named after him. Early life John Dalton was born into a Quaker family in Eaglesfield, near Cockermouth, in Cumberland, England. His father was a weaver. He received his early education from his father and from Quaker John Fletcher, who ran a private school in the nearby village of Pardshaw Hall. Dalton's family was too poor to support him for long and he began to earn his living, from the age of ten, in the service of wealthy local Quaker Elihu Robinson. Early career When he was 15, Dalton joined his older brother Jonathan in running a Quaker school in Kendal, Westmorland, about from his home. Around the age of 23, Dalton may have considered studying law or medicin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hans Bethe
Hans Albrecht Bethe (; July 2, 1906 – March 6, 2005) was a German-American theoretical physicist who made major contributions to nuclear physics, astrophysics, quantum electrodynamics, and solid-state physics, and who won the 1967 Nobel Prize in Physics for his work on the theory of stellar nucleosynthesis. For most of his career, Bethe was a professor at Cornell University.Available at www.JamesKeckCollectedWorks.or are the class notes taken by one of his students at Cornell from the graduate courses on Nuclear Physics and on Applications of Quantum Mechanics he taught in the spring of 1947. During World War II, he was head of the Theoretical Division at the secret Los Alamos National Laboratory, Los Alamos laboratory that developed the first atomic bombs. There he played a key role in calculating the critical mass of the weapons and developing the theory behind the implosion method used in both the Trinity test and the "Fat Man" weapon dropped on Nagasaki in August 1945. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
George Gamow
George Gamow (March 4, 1904 – August 19, 1968), born Georgiy Antonovich Gamov ( uk, Георгій Антонович Гамов, russian: Георгий Антонович Гамов), was a Russian-born Soviet and American polymath, theoretical physicist and cosmologist. He was an early advocate and developer of Lemaître's Big Bang theory. He discovered a theoretical explanation of alpha decay by quantum tunneling, invented the liquid drop model and the first mathematical model of the atomic nucleus, and worked on radioactive decay, star formation, stellar nucleosynthesis and Big Bang nucleosynthesis (which he collectively called nucleocosmogenesis), and molecular genetics. In his middle and late career, Gamow directed much of his attention to teaching and wrote popular books on science, including '' One Two Three... Infinity'' and the ''Mr Tompkins'' series of books (1939–1967). Some of his books are still in print more than a half-century after their original publicat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ralph Alpher
Ralph Asher Alpher (February 3, 1921 – August 12, 2007) was an American cosmologist, who carried out pioneering work in the early 1950s on the Big Bang model, including Big Bang nucleosynthesis and predictions of the cosmic microwave background radiation. Childhood and education Alpher was the son of a Russian Empire Jewish immigrant, Samuel Alpher (born Alfirevich), from Vitebsk, Russian Empire. His mother, Rose Maleson, died of stomach cancer in 1938, and his father later remarried. Alpher graduated at age 15 from Theodore Roosevelt High School in Washington, D.C., and held the ranks of Major and Commander of his school's Cadet program. He worked in the high school theater as stage manager for two years, supplementing his family's Depression-era income. He also learned Gregg shorthand, and in 1937 began working for the Director of the American Geophysical Union as a stenographer. In 1940 he was hired by the Department of Terrestrial Magnetism of the Carnegie Foundation, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greek Alphabet
The Greek alphabet has been used to write the Greek language since the late 9th or early 8th century BCE. It is derived from the earlier Phoenician alphabet, and was the earliest known alphabetic script to have distinct letters for vowels as well as consonants. In Archaic Greece, Archaic and early Classical Greece, Classical times, the Greek alphabet existed in Archaic Greek alphabets, many local variants, but, by the end of the 4th century BCE, the Euclidean alphabet, with 24 letters, ordered from alpha to omega, had become standard and it is this version that is still used for Greek writing today. The letter case, uppercase and lowercase forms of the 24 letters are: : , , , , , , , , , , , , , , , , , /ς, , , , , , . The Greek alphabet is the ancestor of the Latin script, Latin and Cyrillic scripts. Like Latin and Cyrillic, Greek originally had only a single form of each letter; it developed the letter case distinction between uppercase and lowercase in parallel with Latin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theocracy
Theocracy is a form of government in which one or more deity, deities are recognized as supreme ruling authorities, giving divine guidance to human intermediaries who manage the government's daily affairs. Etymology The word theocracy originates from the el, θεοκρατία () meaning "the rule of God". This, in turn, derives from :wikt:θεός, θεός (theos), meaning "god", and :wikt:κρατέω, κρατέω (''krateo''), meaning "to rule". Thus the meaning of the word in Greek was "rule by god(s)" or human incarnation(s) of god(s). The term was initially coined by Flavius Josephus in the first century AD to describe the characteristic government of the Jews. Josephus argued that while mankind had developed many forms of rule, most could be subsumed under the following three types: monarchy, oligarchy, and democracy. However, according to Josephus, the government of the Jews was unique. Josephus offered the term "theocracy" to describe this polity in which God was s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Merchant
A merchant is a person who trades in commodities produced by other people, especially one who trades with foreign countries. Historically, a merchant is anyone who is involved in business or trade. Merchants have operated for as long as industry, commerce, and trade have existed. In 16th-century Europe, two different terms for merchants emerged: referred to local traders (such as bakers and grocers) and ( nl, koopman) referred to merchants who operated on a global stage, importing and exporting goods over vast distances and offering added-value services such as credit and finance. The status of the merchant has varied during different periods of history and among different societies. In modern times, the term ''merchant'' has occasionally been used to refer to a businessperson or someone undertaking activities (commercial or industrial) for the purpose of generating profit, cash flow, sales, and revenue using a combination of human, financial, intellectual and physical capit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pendulum
A pendulum is a weight suspended from a pivot so that it can swing freely. When a pendulum is displaced sideways from its resting, equilibrium position, it is subject to a restoring force due to gravity that will accelerate it back toward the equilibrium position. When released, the restoring force acting on the pendulum's mass causes it to oscillate about the equilibrium position, swinging back and forth. The time for one complete cycle, a left swing and a right swing, is called the period. The period depends on the length of the pendulum and also to a slight degree on the amplitude, the width of the pendulum's swing. From the first scientific investigations of the pendulum around 1602 by Galileo Galilei, the regular motion of pendulums was used for timekeeping and was the world's most accurate timekeeping technology until the 1930s. The pendulum clock invented by Christiaan Huygens in 1658 became the world's standard timekeeper, used in homes and offices for 270 years, and ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
