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Orbit Of Mars
Mars has an orbit with a semimajor axis of 1.524 astronomical units (228 million km) (12.673 light minutes), and an orbital eccentricity, eccentricity of 0.0934.Jean Meeus, ''Astronomical Formulæ for Calculators''. (Richmond, VA: Willmann-Bell, 1988) 99. Elements by F. E. Ross The planet orbits the Sun in 687 days and travels 9.55 AU in doing so,Jean Meeus, ''Astronomical Algorithms'' (Richmond, VA: Willmann-Bell, 1998) 238. The formula by Ramanujan is accurate enough. making the average orbital speed 24 km/s. The eccentricity is greater than that of any other planet except Mercury, and this causes a large difference between the Apsis, aphelion and perihelion distances—they are respectively 1.666 and 1.381 AU.; Mean Anomaly (deg) 19.412 = (Mean Longitude (deg) 355.45332) – (Longitude of perihelion (deg) 336.04084) Changes in the orbit Mars is in the midst of a long-term increase in eccentricity. It reached a minimum of 0.079 about 19 millennia ago, and wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nicolaus Copernicus
Nicolaus Copernicus (19 February 1473 – 24 May 1543) was a Renaissance polymath who formulated a mathematical model, model of Celestial spheres#Renaissance, the universe that placed heliocentrism, the Sun rather than Earth at its center. Copernicus likely developed his model independently of Aristarchus of Samos, an List of ancient Greek astronomers, ancient Greek astronomer who had formulated such a model some eighteen centuries earlier. The publication of Copernicus' model in his book ' (''On the Revolutions of the Celestial Spheres''), just before his death in 1543, was a major event in the history of science, triggering the Copernican Revolution and making a pioneering contribution to the Scientific Revolution. Copernicus was born and died in Royal Prussia, a semiautonomous and multilingual region created within the Crown of the Kingdom of Poland from lands regained from the Teutonic Order after the Thirteen Years' War (1454–1466), Thirteen Years' War. A Poly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accuracy And Precision
Accuracy and precision are two measures of ''observational error''. ''Accuracy'' is how close a given set of measurements (observations or readings) are to their ''true value''. ''Precision'' is how close the measurements are to each other. The International Organization for Standardization (ISO) defines a related measure: ''trueness'', "the closeness of agreement between the arithmetic mean of a large number of test results and the true or accepted reference value." While ''precision'' is a description of ''random errors'' (a measure of statistical variability), ''accuracy'' has two different definitions: # More commonly, a description of ''systematic errors'' (a measure of statistical bias of a given measure of central tendency, such as the mean). In this definition of "accuracy", the concept is independent of "precision", so a particular set of data can be said to be accurate, precise, both, or neither. This concept corresponds to ISO's ''trueness''. # A combination of both ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbital Elements
Orbital elements are the parameters required to uniquely identify a specific orbit. In celestial mechanics these elements are considered in two-body systems using a Kepler orbit. There are many different ways to mathematically describe the same orbit, but certain schemes are commonly used in astronomy and orbital mechanics. A real orbit and its elements change over time due to gravitational Perturbation (astronomy), perturbations by other objects and the effects of general relativity. A Kepler orbit is an idealized, mathematical approximation of the orbit at a particular time. When viewed from an inertial frame, two orbiting bodies trace out distinct trajectories. Each of these trajectories has its Focus (geometry), focus at the common center of mass. When viewed from a non-inertial frame centered on one of the bodies, only the trajectory of the opposite body is apparent; Keplerian elements describe these non-inertial trajectories. An orbit has two sets of Keplerian elements depe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Significant Figures
Significant figures, also referred to as significant digits, are specific digits within a number that is written in positional notation that carry both reliability and necessity in conveying a particular quantity. When presenting the outcome of a measurement (such as length, pressure, volume, or mass), if the number of digits exceeds what the measurement instrument can resolve, only the digits that are determined by the resolution are dependable and therefore considered significant. For instance, if a length measurement yields 114.8 mm, using a ruler with the smallest interval between marks at 1 mm, the first three digits (1, 1, and 4, representing 114 mm) are certain and constitute significant figures. Further, digits that are uncertain yet meaningful are also included in the significant figures. In this example, the last digit (8, contributing 0.8 mm) is likewise considered significant despite its uncertainty. Therefore, this measurement contains ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asteroid Belt
The asteroid belt is a torus-shaped region in the Solar System, centered on the Sun and roughly spanning the space between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies called asteroids or minor planets. The identified objects are of many sizes, but much smaller than planets, and, on average, are about one million kilometers (or six hundred thousand miles) apart. This asteroid belt is also called the main asteroid belt or main belt to distinguish it from other asteroid populations in the Solar System. The asteroid belt is the smallest and innermost circumstellar disc in the Solar System. Classes of Small Solar System body, small Solar System bodies in other regions are the near-Earth objects, the Centaur (minor planet), centaurs, the Kuiper belt objects, the scattered disc objects, the sednoids, and the Oort cloud objects. About 60% of the main belt mass is contained in the four largest asteroids: Ceres (dwarf planet), C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldo Vitagliano
Aldo may refer to: * Aldo (given name), male given name ** Aldo (footballer, born 1957) ** Aldo (footballer, born 1977) ** Aldo (footballer, born 1988) * Aldo Group, a worldwide chain of shoe stores * Aldosterone Aldosterone is the main mineralocorticoid steroid hormone produced by the zona glomerulosa of the adrenal cortex in the adrenal gland. It is essential for sodium conservation in the kidney, salivary glands, sweat glands, and colon. It plays ... in shorthand * Aldo Bonzi, a town in Argentina {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encyclopædia Britannica Online
An encyclopedia is a reference work or compendium providing summaries of knowledge, either general or special, in a particular field or discipline. Encyclopedias are divided into articles or entries that are arranged alphabetically by article name or by thematic categories, or else are hyperlinked and searchable. Encyclopedia entries are longer and more detailed than those in most dictionaries. Generally speaking, encyclopedia articles focus on ''factual information'' concerning the subject named in the article's title; this is unlike dictionary entries, which focus on linguistic information about words, such as their etymology, meaning, pronunciation, use, and grammatical forms.Béjoint, Henri (2000)''Modern Lexicography'', pp. 30–31. Oxford University Press. Encyclopedias have existed for around 2,000 years and have evolved considerably during that time as regards language (written in a major international or a vernacular language), size (few or many volumes), intent ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler's Laws Of Planetary Motion
In astronomy, Kepler's laws of planetary motion, published by Johannes Kepler in 1609 (except the third law, which was fully published in 1619), describe the orbits of planets around the Sun. These laws replaced circular orbits and epicycles in the heliocentric theory of Nicolaus Copernicus with elliptical orbits and explained how planetary velocities vary. The three laws state that: # The orbit of a planet is an ellipse with the Sun at one of the two foci. # A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time. # The square of a planet's orbital period is proportional to the cube of the length of the semi-major axis of its orbit. The elliptical orbits of planets were indicated by calculations of the orbit of Mars. From this, Kepler inferred that other bodies in the Solar System, including those farther away from the Sun, also have elliptical orbits. The second law establishes that when a planet is closer to the Sun, it travels fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Focus (geometry)
In geometry, focuses or foci (; : focus) are special points with reference to which any of a variety of curves is constructed. For example, one or two foci can be used in defining conic sections, the four types of which are the circle, ellipse, parabola, and hyperbola. In addition, two foci are used to define the Cassini oval and the Cartesian oval, and more than two foci are used in defining an n-ellipse, ''n''-ellipse. Conic sections Defining conics in terms of two foci An ellipse can be defined as the locus (mathematics), locus of points for which the sum of the distances to two given foci is constant. A circle is the special case of an ellipse in which the two foci coincide with each other. Thus, a circle can be more simply defined as the locus of points each of which is a fixed distance from a single given focus. A circle can also be defined as the Circles of Apollonius, circle of Apollonius, in terms of two different foci, as the locus of points having a fixed ratio of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ellipse
In mathematics, an ellipse is a plane curve surrounding two focus (geometry), focal points, such that for all points on the curve, the sum of the two distances to the focal points is a constant. It generalizes a circle, which is the special type of ellipse in which the two focal points are the same. The elongation of an ellipse is measured by its eccentricity (mathematics), eccentricity e, a number ranging from e = 0 (the Limiting case (mathematics), limiting case of a circle) to e = 1 (the limiting case of infinite elongation, no longer an ellipse but a parabola). An ellipse has a simple algebraic solution for its area, but for Perimeter of an ellipse, its perimeter (also known as circumference), Integral, integration is required to obtain an exact solution. The largest and smallest diameters of an ellipse, also known as its width and height, are typically denoted and . An ellipse has four extreme points: two ''Vertex (geometry), vertices'' at the endpoints of the major axis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tycho Brahe
Tycho Brahe ( ; ; born Tyge Ottesen Brahe, ; 14 December 154624 October 1601), generally called Tycho for short, was a Danish astronomer of the Renaissance, known for his comprehensive and unprecedentedly accurate astronomical observations. He was known during his lifetime as an astronomer, astrologer, and alchemist. He was the last major astronomer before the invention of the telescope. Tycho Brahe has also been described as the greatest pre-telescopic astronomer. In 1572, Tycho noticed a completely SN 1572, new star that was brighter than any star or planet. Astonished by the existence of a star that ought not to have been there, he devoted himself to the creation of ever more accurate instruments of measurement over the next fifteen years (1576–1591). Frederick II of Denmark, King Frederick II granted Tycho an estate on the island of Hven and the money to build Uraniborg, the first large observatory in Christian Europe. He later worked underground at Stjerneborg, where he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
