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Naburimannu
{{Short description, Ancient astronomer and mathematician Nabu-ri (cuneiform), ri-man-nu (also spelled ''Nabu-rimanni''; Greek sources called him Ναβουριανός, ''Nabourianos'', Latin ''Naburianus'') (floruit, fl. c. 6th – 3rd century BC) was a Babylonian astronomy, Chaldean astronomer and Babylonian mathematics, mathematician. Classical and ancient cuneiform sources mention an astronomer with this name: * The Greek geographer Strabo of Amaseia, in ''Geography'' 16.1–.6, writes: "In Babylon a settlement is set apart for the local philosophers, the Chaldea, Chaldaeans, as they are called, who are concerned mostly with astronomy; but some of these, who are not approved of by the others, profess to be writers of horoscopes. (There is also a tribe of the Chaldaeans, and a territory inhabited by them, in the neighborhood of the Arabia, Arabs and of the Persian Gulf, as it is called.) There are also several tribes of the Chaldaean astronomers. For example, some are called Orc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kidinnu
Kidinnu (also ''Kidunnu''; possibly fl. 4th century BC; possibly died 14 August 330 BC) was a Chaldean astronomer and mathematician. Strabo of Amaseia called him Kidenas, Pliny the Elder called him Cidenas, and Vettius Valens called him Kidynas. Some cuneiform and classical Greek and Latin texts mention an astronomer with this name, but it is not clear if they all refer to the same individual: * The Greek geographer Strabo of Amaseia, in ''Geography'' 16.1.6, writes: "In Babylon a settlement is set apart for the local philosophers, the Chaldeans, as they are called, who are concerned mostly with astronomy; but some of these, who are not approved of by the others, profess to be writers of horoscopes. (There is also a tribe of the Chaldeans, and a territory inhabited by them, in the neighborhood of the Arabs and of the Persian Gulf, as it is called.) There are also several tribes of the Chaldean astronomers. For example, some are called Orcheni Uruk.html" ;"title="hose from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Babylonian Astronomy
Babylonian astronomy was the study or recording of celestial objects during the early history of Mesopotamia. The numeral system used, sexagesimal, was based on 60, as opposed to ten in the modern decimal system. This system simplified the calculating and recording of unusually great and small numbers. During the 8th and 7th centuries BC, Babylonian astronomers developed a new empirical approach to astronomy. They began studying and recording their belief system and philosophies dealing with an ideal nature of the universe and began employing an internal logic within their predictive planetary systems. This was an important contribution to astronomy and the philosophy of science, and some modern scholars have thus referred to this approach as a scientific revolution. This approach to astronomy was adopted and further developed in Greek and Hellenistic astrology. Classical Greek and Latin sources frequently use the term Chaldeans for the philosophers, who were cons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soudines
Sudines (or Soudines) () () was a Babylonian sage. He is mentioned as one of the famous Chaldean mathematicians and astronomer-astrologers by later Roman writers like Strabo (''Geographia'' 16:1–6). Biography Like his predecessor Berossos, Sudines moved from Babylonia and established himself among the Greeks; he was an advisor to King Attalus I (Attalos Soter) of Pergamon. He is said (e.g., by Roman astronomer/astrologer Vettius Valens) to have published tables to compute the motion of the Moon; said to have been used by the Greeks, until superseded by the work of Hipparchus and later by Ptolemy (Claudius Ptolemaios). Sudines may have been important in transmitting the astronomical knowledge of the Babylonians to the Greeks, but little is known about his work and nothing about his life. He is also said to have been one of the first to assign astrological meaning to gemstones. Identity While other Chaldean astronomers have been tentatively identified in the cuneiform record, no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury (planet)
Mercury is the first planet from the Sun. It is a rocky planet with a trace atmosphere. While it is the List of Solar System objects by size, smallest and least massive planet of the Solar System, its surface gravity is slightly higher than that of Mars. The surface of Mercury is similar to Earth's Moon, heavily Impact crater, cratered, with expansive rupes system, generated from thrust faults, and bright ray systems, formed by ejecta. Its largest crater, Caloris Planitia, has a diameter of , which is about one-third the diameter of the planet (). Being the most inferior planet, inferior orbiting planet it appears in Earth's sky, always close to the Sun, either as a "morning star" or an "evening star". It stays most of the time the closest to all other planets and is the planet with the highest delta-v needed to travel to from all other planets of the Solar System. Mercury's sidereal year (88.0 Earth days) and sidereal day (58.65 Earth days) are in a 3:2 ratio. This relation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planet
A planet is a large, Hydrostatic equilibrium, rounded Astronomical object, astronomical body that is generally required to be in orbit around a star, stellar remnant, or brown dwarf, and is not one itself. The Solar System has eight planets by the most restrictive definition of the term: the terrestrial planets Mercury (planet), Mercury, Venus, Earth, and Mars, and the giant planets Jupiter, Saturn, Uranus, and Neptune. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a young protostar orbited by a protoplanetary disk. Planets grow in this disk by the gradual accumulation of material driven by gravity, a process called accretion (astrophysics), accretion. The word ''planet'' comes from the Greek () . In Classical antiquity, antiquity, this word referred to the Sun, Moon, and five points of light visible to the naked eye that moved across the background of the stars—namely, Me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linear Function
In mathematics, the term linear function refers to two distinct but related notions: * In calculus and related areas, a linear function is a function whose graph is a straight line, that is, a polynomial function of degree zero or one. For distinguishing such a linear function from the other concept, the term ''affine function'' is often used. * In linear algebra, mathematical analysis, and functional analysis, a linear function is a linear map. As a polynomial function In calculus, analytic geometry and related areas, a linear function is a polynomial of degree one or less, including the zero polynomial (the latter not being considered to have degree zero). When the function is of only one variable, it is of the form :f(x)=ax+b, where and are constants, often real numbers. The graph of such a function of one variable is a nonvertical line. is frequently referred to as the slope of the line, and as the intercept. If ''a > 0'' then the gradient is positive an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zigzag
A zigzag is a pattern made up of small corners at variable angles, though constant within the zigzag, tracing a path between two parallel lines; it can be described as both jagged and fairly regular. In geometry, this pattern is described as a Infinite skew polygon, skew apeirogon. From the point of view of symmetry, a regular zigzag can be generated from a simple motif like a line segment by repeated application of a glide reflection. Although the origin of the word is unclear, its first printed appearances were in French-language books and ephemera of the late 17th century. Examples of zigzags * The trace of a triangle wave or a sawtooth wave is a zigzag. * Pinking shears are designed to cut cloth or paper with a zigzag edge, to lessen fraying. * In sewing, a ''zigzag stitch'' is a sewing machine, machine stitch in a zigzag pattern. * The zigzag arch is an architectural embellishment used in Islamic architecture, Islamic, Byzantine architecture, Byzantine, Norman archite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Step Function
In mathematics, a function on the real numbers is called a step function if it can be written as a finite linear combination of indicator functions of intervals. Informally speaking, a step function is a piecewise constant function having only finitely many pieces. Definition and first consequences A function f\colon \mathbb \rightarrow \mathbb is called a step function if it can be written as :f(x) = \sum\limits_^n \alpha_i \chi_(x), for all real numbers x where n\ge 0, \alpha_i are real numbers, A_i are intervals, and \chi_A is the indicator function of A: :\chi_A(x) = \begin 1 & \text x \in A \\ 0 & \text x \notin A \\ \end In this definition, the intervals A_i can be assumed to have the following two properties: # The intervals are pairwise disjoint: A_i \cap A_j = \emptyset for i \neq j # The union of the intervals is the entire real line: \bigcup_^n A_i = \mathbb R. Indeed, if that is not the case to start with, a different set of intervals can be picked for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Darius I
Darius I ( ; – 486 BCE), commonly known as Darius the Great, was the third King of Kings of the Achaemenid Empire, reigning from 522 BCE until his death in 486 BCE. He ruled the empire at its territorial peak, when it included much of West Asia, parts of the Balkans (Skudra, Thrace–Achaemenid Macedonia, Macedonia and Paeonia (kingdom), Paeonia) and the Caucasus, most of the Black Sea's coastal regions, Central Asia, the Achaemenid conquest of the Indus Valley, Indus Valley in the far east, and portions of North Africa and Northeast Africa including History of Persian Egypt, Egypt (), eastern ancient Libya, Libya, and coastal The Sudans, Sudan. Darius ascended the throne by overthrowing the Achaemenid monarch Bardiya (or ''Smerdis''), who he claimed was in fact an imposter named Gaumata. The new king met with rebellions throughout the empire but quelled each of them; a major event in Darius's life was his expedition to subjugate Ancient Greece, Greece and punish Classical At ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bartel Leendert Van Der Waerden
Bartel Leendert van der Waerden (; 2 February 1903 – 12 January 1996) was a Dutch mathematician and historian of mathematics. Biography Education and early career Van der Waerden learned advanced mathematics at the University of Amsterdam and the University of Göttingen, from 1919 until 1926. He was much influenced by Emmy Noether at Göttingen, Germany. Amsterdam awarded him a Ph.D. for a thesis on algebraic geometry, supervised by Hendrick de Vries. Göttingen awarded him the habilitation in 1928. In that year, at the age of 25, he accepted a professorship at the University of Groningen. At 27, Van der Waerden published his '' Moderne Algebra'', an influential two-volume treatise on abstract algebra, still cited, and perhaps the first treatise to treat the subject as a comprehensive whole. This work systematized an ample body of research by Emmy Noether, David Hilbert, Richard Dedekind, and Emil Artin. In the following year, 1931, he was appointed professor at the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otto E
Otto is a masculine German given name and a surname. It originates as an Old High German short form (variants '' Audo'', '' Odo'', '' Udo'') of Germanic names beginning in ''aud-'', an element meaning "wealth, prosperity". The name is recorded from the 7th century ( Odo, son of Uro, courtier of Sigebert III). It was the name of three 10th-century German kings, the first of whom was Otto I the Great, the first Holy Roman Emperor, founder of the Ottonian dynasty. The Gothic form of the prefix was ''auda-'' (as in e.g. '' Audaþius''), the Anglo-Saxon form was ''ead-'' (as in e.g. '' Eadmund''), and the Old Norse form was '' auð-''. Due to Otto von Bismarck, the given name ''Otto'' was strongly associated with the German Empire in the later 19th century. It was comparatively frequently given in the United States (presumably in German American families) during the 1880s to 1890s, remaining in the top 100 most popular masculine given names in the US throughout 1880–1898, but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar System
The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar System" and "solar system" structures in theinaming guidelines document. The name is commonly rendered in lower case ('solar system'), as, for example, in the ''Oxford English Dictionary'' an''Merriam-Webster's 11th Collegiate Dictionary''. is the gravitationally bound Planetary system, system of the Sun and the objects that orbit it. It Formation and evolution of the Solar System, formed about 4.6 billion years ago when a dense region of a molecular cloud collapsed, forming the Sun and a protoplanetary disc. The Sun is a typical star that maintains a hydrostatic equilibrium, balanced equilibrium by the thermonuclear fusion, fusion of hydrogen into helium at its stellar core, core, releasing this energy from its outer photosphere. As ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
