72 relations: Andrey Kolmogorov, Antarctic Circle, Apparent retrograde motion, Apsis, Arctic Circle, Argument of periapsis, Aristarchus of Samos, Astronomical unit, Axial tilt, Barycenter, Carl Friedrich Gauss, Clockwise, Copernican heliocentrism, Copernican Revolution, De revolutionibus orbium coelestium, Diurnal motion, Earth, Earth's rotation, Ecliptic, Epoch (astronomy), Equator, Equinox, Fixed stars, Frequency, Geocentric model, Geocentric orbit, Gravity, Heliocentrism, Henri Poincaré, Hill sphere, Invariable plane, IOP Publishing, Jacques Laskar, Jürgen Moser, Jean Meeus, Joan Blaeu, Joseph-Louis Lagrange, Kilometre, Longitude of the ascending node, Longitude of the periapsis, Lunar distance (astronomy), Milankovitch cycles, Moon, N-body problem, NASA, Nicolaus Copernicus, Orbit, Orbital eccentricity, Orbital inclination, Orbital period, ..., Orbital speed, Perihelion and aphelion, Pierre-Simon Laplace, Polar night, Precession, Ptolemy, Random House, Retrograde and prograde motion, Satellite, Season, Secular variation, Semi-major and semi-minor axes, Sidereal year, Solar System, Solar time, Solstice, Space station, Sun, Tropic of Cancer, Tropic of Capricorn, Vladimir Arnold, Winter solstice. Expand index (22 more) » « Shrink index
Andrey Nikolaevich Kolmogorov (a, 25 April 1903 – 20 October 1987) was a 20th-century Soviet mathematician who made significant contributions to the mathematics of probability theory, topology, intuitionistic logic, turbulence, classical mechanics, algorithmic information theory and computational complexity.
The Antarctic Circle is the most southerly of the five major circles of latitude that mark maps of the Earth.
Apparent retrograde motion is the apparent motion of a planet in a direction opposite to that of other bodies within its system, as observed from a particular vantage point.
An apsis (ἁψίς; plural apsides, Greek: ἁψῖδες) is an extreme point in the orbit of an object.
The Arctic Circle is the most northerly of the five major circles of latitude as shown on maps of Earth.
The argument of periapsis (also called argument of perifocus or argument of pericenter), symbolized as ω, is one of the orbital elements of an orbiting body.
Aristarchus of Samos (Ἀρίσταρχος ὁ Σάμιος, Aristarkhos ho Samios; c. 310 – c. 230 BC) was an ancient Greek astronomer and mathematician who presented the first known model that placed the Sun at the center of the known universe with the Earth revolving around it (see Solar system).
The astronomical unit (symbol: au, ua, or AU) is a unit of length, roughly the distance from Earth to the Sun.
In astronomy, axial tilt, also known as obliquity, is the angle between an object's rotational axis and its orbital axis, or, equivalently, the angle between its equatorial plane and orbital plane.
The barycenter (or barycentre; from the Ancient Greek βαρύς heavy + κέντρον centre) is the center of mass of two or more bodies that are orbiting each other, which is the point around which they both orbit.
Johann Carl Friedrich Gauss (Gauß; Carolus Fridericus Gauss; 30 April 177723 February 1855) was a German mathematician and physicist who made significant contributions to many fields, including algebra, analysis, astronomy, differential geometry, electrostatics, geodesy, geophysics, magnetic fields, matrix theory, mechanics, number theory, optics and statistics.
Two-dimensional rotation can occur in two possible directions.
Copernican heliocentrism is the name given to the astronomical model developed by Nicolaus Copernicus and published in 1543.
The Copernican Revolution was the paradigm shift from the Ptolemaic model of the heavens, which described the cosmos as having Earth stationary at the center of the universe, to the heliocentric model with the Sun at the center of the Solar System.
De revolutionibus orbium coelestium (On the Revolutions of the Heavenly Spheres) is the seminal work on the heliocentric theory of the Renaissance astronomer Nicolaus Copernicus (1473–1543).
Diurnal motion (lit, from dies, lit. "day") is an astronomical term referring to the apparent daily motion of stars around Earth, or more precisely around the two celestial poles.
Earth is the third planet from the Sun and the only astronomical object known to harbor life.
Earth's rotation is the rotation of Planet Earth around its own axis.
The ecliptic is the circular path on the celestial sphere that the Sun follows over the course of a year; it is the basis of the ecliptic coordinate system.
In astronomy, an epoch is a moment in time used as a reference point for some time-varying astronomical quantity, such as the celestial coordinates or elliptical orbital elements of a celestial body, because these are subject to perturbations and vary with time.
An equator of a rotating spheroid (such as a planet) is its zeroth circle of latitude (parallel).
An equinox is commonly regarded as the moment the plane (extended indefinitely in all directions) of Earth's equator passes through the center of the Sun, which occurs twice each year, around 20 March and 22-23 September.
The fixed stars (stellae fixae) comprise the background of astronomical objects that appear to not move relative to each other in the night sky compared to the foreground of Solar System objects that do.
Frequency is the number of occurrences of a repeating event per unit of time.
In astronomy, the geocentric model (also known as geocentrism, or the Ptolemaic system) is a superseded description of the universe with Earth at the center.
A geocentric orbit or Earth orbit involves any object orbiting Planet Earth, such as the Moon or artificial satellites.
Gravity, or gravitation, is a natural phenomenon by which all things with mass or energy—including planets, stars, galaxies, and even light—are brought toward (or gravitate toward) one another.
Heliocentrism is the astronomical model in which the Earth and planets revolve around the Sun at the center of the Solar System.
Jules Henri Poincaré (29 April 1854 – 17 July 1912) was a French mathematician, theoretical physicist, engineer, and philosopher of science.
An astronomical body's Hill sphere is the region in which it dominates the attraction of satellites.
The invariable plane of a planetary system, also called Laplace's invariable plane, is the plane passing through its barycenter (center of mass) perpendicular to its angular momentum vector.
IOP Publishing (previously named Institute of Physics Publishing) is the publishing company of the Institute of Physics.
Jacques Laskar (born 28 April 1955 in Paris) is a French astronomer.
Jürgen Kurt Moser (July 4, 1928 – December 17, 1999) was an award-winning, German-American mathematician, honored for work spanning over 4 decades, including Hamiltonian dynamical systems and partial differential equations.
Jean Meeus (born 12 December 1928) is a Belgian meteorologist and amateur astronomer specializing in celestial mechanics, spherical and mathematical astronomy.
Joan Blaeu (23 September 1596 – 21 December 1673) was a Dutch cartographer born in Alkmaar, the son of cartographer Willem Blaeu.
Joseph-Louis Lagrange (or;; born Giuseppe Lodovico Lagrangia, Encyclopædia Britannica or Giuseppe Ludovico De la Grange Tournier, Turin, 25 January 1736 – Paris, 10 April 1813; also reported as Giuseppe Luigi Lagrange or Lagrangia) was an Italian Enlightenment Era mathematician and astronomer.
The kilometre (International spelling as used by the International Bureau of Weights and Measures; SI symbol: km; or) or kilometer (American spelling) is a unit of length in the metric system, equal to one thousand metres (kilo- being the SI prefix for). It is now the measurement unit used officially for expressing distances between geographical places on land in most of the world; notable exceptions are the United States and the road network of the United Kingdom where the statute mile is the official unit used.
The longitude of the ascending node (☊ or Ω) is one of the orbital elements used to specify the orbit of an object in space.
In celestial mechanics, the longitude of the periapsis, also called longitude of the pericenter, of an orbiting body is the longitude (measured from the point of the vernal equinox) at which the periapsis (closest approach to the central body) would occur if the body's orbit inclination were zero.
Lunar distance (LD or \Delta_), also called Earth–Moon distance, Earth–Moon characteristic distance, or distance to the Moon, is a unit of measure in astronomy.
Milankovitch cycles describe the collective effects of changes in the Earth's movements on its climate over thousands of years.
The Moon is an astronomical body that orbits planet Earth and is Earth's only permanent natural satellite.
In physics, the -body problem is the problem of predicting the individual motions of a group of celestial objects interacting with each other gravitationally.
The National Aeronautics and Space Administration (NASA) is an independent agency of the executive branch of the United States federal government responsible for the civilian space program, as well as aeronautics and aerospace research.
Nicolaus Copernicus (Mikołaj Kopernik; Nikolaus Kopernikus; Niklas Koppernigk; 19 February 1473 – 24 May 1543) was a Renaissance-era mathematician and astronomer who formulated a model of the universe that placed the Sun rather than the Earth at the center of the universe, likely independently of Aristarchus of Samos, who had formulated such a model some eighteen centuries earlier.
In physics, an orbit is the gravitationally curved trajectory of an object, such as the trajectory of a planet around a star or a natural satellite around a planet.
The orbital eccentricity of an astronomical object is a parameter that determines the amount by which its orbit around another body deviates from a perfect circle.
Orbital inclination measures the tilt of an object's orbit around a celestial body.
The orbital period is the time a given astronomical object takes to complete one orbit around another object, and applies in astronomy usually to planets or asteroids orbiting the Sun, moons orbiting planets, exoplanets orbiting other stars, or binary stars.
In gravitationally bound systems, the orbital speed of an astronomical body or object (e.g. planet, moon, artificial satellite, spacecraft, or star) is the speed at which it orbits around either the barycenter or, if the object is much less massive than the largest body in the system, its speed relative to that largest body.
The perihelion of any orbit of a celestial body about the Sun is the point where the body comes nearest to the Sun.
Pierre-Simon, marquis de Laplace (23 March 1749 – 5 March 1827) was a French scholar whose work was important to the development of mathematics, statistics, physics and astronomy.
The polar night occurs in the northernmost and southernmost regions of the Earth when the night lasts for more than 24 hours.
Precession is a change in the orientation of the rotational axis of a rotating body.
Claudius Ptolemy (Κλαύδιος Πτολεμαῖος, Klaúdios Ptolemaîos; Claudius Ptolemaeus) was a Greco-Roman mathematician, astronomer, geographer, astrologer, and poet of a single epigram in the Greek Anthology.
Random House is an American book publisher and the largest general-interest paperback publisher in the world.
Retrograde motion in astronomy is, in general, orbital or rotational motion of an object in the direction opposite the rotation of its primary, that is the central object (right figure).
In the context of spaceflight, a satellite is an artificial object which has been intentionally placed into orbit.
A season is a division of the year marked by changes in weather, ecology, and amount of daylight.
The secular variation of a time series is its long-term non-periodic variation (see Decomposition of time series).
In geometry, the major axis of an ellipse is its longest diameter: a line segment that runs through the center and both foci, with ends at the widest points of the perimeter.
A sidereal year (from Latin sidus "asterism, star") is the time taken by the Earth to orbit the Sun once with respect to the fixed stars.
The Solar SystemCapitalization of the name varies.
Solar time is a calculation of the passage of time based on the position of the Sun in the sky.
A solstice is an event occurring when the Sun appears to reach its most northerly or southerly excursion relative to the celestial equator on the celestial sphere.
A space station, also known as an orbital station or an orbital space station, is a spacecraft capable of supporting crewmembers, which is designed to remain in space (most commonly as an artificial satellite in low Earth orbit) for an extended period of time and for other spacecraft to dock.
The Sun is the star at the center of the Solar System.
The Tropic of Cancer, also referred to as the Northern Tropic, is the most northerly circle of latitude on Earth at which the Sun can be directly overhead.
The Tropic of Capricorn (or the Southern Tropic) is the circle of latitude that contains the subsolar point on the December (or southern) solstice.
Vladimir Igorevich Arnold (alternative spelling Arnol'd, Влади́мир И́горевич Арно́льд, 12 June 1937 – 3 June 2010) was a Soviet and Russian mathematician.
The winter solstice (or hibernal solstice), also known as midwinter, is an astronomical phenomenon marking the day with the shortest period of daylight and the longest night of the year.
Earth revolution, Earth's Orbit, Earth's revolution, Earths Orbit, Orbit of Earth, Orbit of the Earth, Orbit of the earth, Orbital positions of Earth, Speed Earth orbit, Speed earth orbit, Speed of Earth orbit, Speed of Earth's orbit, Speed of earth orbit, Speed of earth's orbit, Sun-Earth system, Sun–Earth system.