71 relations: Actinide, Altair, American football, Anatomy, Angular momentum, Aspect ratio, Astronomical object, Atomic nucleus, Cartography, Circular symmetry, Crab Nebula, Earth, Earth's rotation, Eccentricity (mathematics), Electromagnetism, Ellipse, Ellipsoid, Enceladus, Equator, Equatorial bulge, Figure of the Earth, Flattening, Fresnel zone, Gaussian curvature, Geodesy, Geographical pole, Gravity, Hal Clement, Imaginary number, Io (moon), Jupiter, Known Space, Larry Niven, Lentil, Lentoid, Longitude, Mean curvature, Mesklin, Mimas (moon), Miranda (moon), Mission of Gravity, Moment of inertia, Natural satellite, Nuclear shell model, Oblate spheroidal coordinates, Oval, Planet, Prolate spheroidal coordinates, Quadric, Quantum mechanics, ..., Reference ellipsoid, Rotation of axes, Rotational symmetry, Rugby football, Saturn, Science fiction, Scientific American, Semi-major and semi-minor axes, Semidiameter, Sphere, Spheroid, Surface (mathematics), Surface area, Surface tension, Testicle, Tethys (moon), Tide, Translation of axes, Uranus, Volcanism, World Geodetic System. Expand index (21 more) » « Shrink index
The actinide or actinoid (IUPAC nomenclature) series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium through lawrencium.
Altair, also designated Alpha Aquilae (α Aquilae, abbreviated Alpha Aql, α Aql), is the brightest star in the constellation of Aquila and the twelfth brightest star in the night sky.
American football, referred to as football in the United States and Canada and also known as gridiron, is a team sport played by two teams of eleven players on a rectangular field with goalposts at each end.
Anatomy (Greek anatomē, “dissection”) is the branch of biology concerned with the study of the structure of organisms and their parts.
In physics, angular momentum (rarely, moment of momentum or rotational momentum) is the rotational equivalent of linear momentum.
The aspect ratio of a geometric shape is the ratio of its sizes in different dimensions.
An astronomical object or celestial object is a naturally occurring physical entity, association, or structure that exists in the observable universe.
The atomic nucleus is the small, dense region consisting of protons and neutrons at the center of an atom, discovered in 1911 by Ernest Rutherford based on the 1909 Geiger–Marsden gold foil experiment.
Cartography (from Greek χάρτης chartēs, "papyrus, sheet of paper, map"; and γράφειν graphein, "write") is the study and practice of making maps.
In geometry, circular symmetry is a type of continuous symmetry for a planar object that can be rotated by any arbitrary angle and map onto itself.
The Crab Nebula (catalogue designations M1, NGC 1952, Taurus A) is a supernova remnant in the constellation of Taurus.
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.
In mathematics, the eccentricity, denoted e or \varepsilon, is a parameter associated with every conic section.
Electromagnetism is a branch of physics involving the study of the electromagnetic force, a type of physical interaction that occurs between electrically charged particles.
In mathematics, an ellipse is a curve in a plane surrounding two focal points such that the sum of the distances to the two focal points is constant for every point on the curve.
An ellipsoid is a surface that may be obtained from a sphere by deforming it by means of directional scalings, or more generally, of an affine transformation.
Enceladus is the sixth-largest moon of Saturn.
An equator of a rotating spheroid (such as a planet) is its zeroth circle of latitude (parallel).
An equatorial bulge is a difference between the equatorial and polar diameters of a planet, due to the force exerted by its rotation.
The figure of the Earth is the size and shape of the Earth in geodesy.
Flattening is a measure of the compression of a circle or sphere along a diameter to form an ellipse or an ellipsoid of revolution (spheroid) respectively.
A Fresnel zone, named for physicist Augustin-Jean Fresnel, is one of a series of concentric prolate ellipsoidal regions of space between and around a transmitting antenna and a receiving antenna system.
In differential geometry, the Gaussian curvature or Gauss curvature Κ of a surface at a point is the product of the principal curvatures, κ1 and κ2, at the given point: For example, a sphere of radius r has Gaussian curvature 1/r2 everywhere, and a flat plane and a cylinder have Gaussian curvature 0 everywhere.
Geodesy, also known as geodetics, is the earth science of accurately measuring and understanding three of Earth's fundamental properties: its geometric shape, orientation in space, and gravitational field.
A geographical pole is either of the two points on a rotating body (planet, dwarf planet, natural satellite, sphere...etc) where its axis of rotation intersects its surface.
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.
Harry Clement Stubbs (May 30, 1922 – October 29, 2003), better known by the pen name Hal Clement, was an American science fiction writer and a leader of the hard science fiction subgenre.
An imaginary number is a complex number that can be written as a real number multiplied by the imaginary unit,j is usually used in Engineering contexts where i has other meanings (such as electrical current) which is defined by its property.
Io (Jupiter I) is the innermost of the four Galilean moons of the planet Jupiter.
Jupiter is the fifth planet from the Sun and the largest in the Solar System.
Known Space is the fictional setting of about a dozen science fiction novels and several collections of short stories written by Larry Niven.
Laurence van Cott Niven (born April 30, 1938) is an American science fiction writer.
The lentil (Lens culinaris or Lens esculenta) is an edible pulse.
Lentoid is a geometric shape of a three-dimensional body, best described as a circle viewed from one direction and a convex lens viewed from every orthogonal direction.
Longitude, is a geographic coordinate that specifies the east-west position of a point on the Earth's surface.
In mathematics, the mean curvature H of a surface S is an extrinsic measure of curvature that comes from differential geometry and that locally describes the curvature of an embedded surface in some ambient space such as Euclidean space.
Mesklin is a fictional supergiant planet created by Hal Clement and used in a number of his hard science fiction stories.
Mimas, also designated Saturn I, is a moon of Saturn which was discovered in 1789 by William Herschel.
Miranda, also designated Uranus V, is the smallest and innermost of Uranus's five round satellites.
Mission of Gravity is a science fiction novel by American writer Hal Clement.
The moment of inertia, otherwise known as the angular mass or rotational inertia, of a rigid body is a tensor that determines the torque needed for a desired angular acceleration about a rotational axis; similar to how mass determines the force needed for a desired acceleration.
A natural satellite or moon is, in the most common usage, an astronomical body that orbits a planet or minor planet (or sometimes another small Solar System body).
In nuclear physics and nuclear chemistry, the nuclear shell model is a model of the atomic nucleus which uses the Pauli exclusion principle to describe the structure of the nucleus in terms of energy levels.
Oblate spheroidal coordinates are a three-dimensional orthogonal coordinate system that results from rotating the two-dimensional elliptic coordinate system about the non-focal axis of the ellipse, i.e., the symmetry axis that separates the foci.
An oval (from Latin ovum, "egg") is a closed curve in a plane which "loosely" resembles the outline of an egg.
A planet is an astronomical body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.
Prolate spheroidal coordinates are a three-dimensional orthogonal coordinate system that results from rotating the two-dimensional elliptic coordinate system about the focal axis of the ellipse, i.e., the symmetry axis on which the foci are located.
In mathematics, a quadric or quadric surface (quadric hypersurface in higher dimensions), is a generalization of conic sections (ellipses, parabolas, and hyperbolas).
Quantum mechanics (QM; also known as quantum physics, quantum theory, the wave mechanical model, or matrix mechanics), including quantum field theory, is a fundamental theory in physics which describes nature at the smallest scales of energy levels of atoms and subatomic particles.
In geodesy, a reference ellipsoid is a mathematically defined surface that approximates the geoid, the truer figure of the Earth, or other planetary body.
In mathematics, a rotation of axes in two dimensions is a mapping from an xy-Cartesian coordinate system to an x'y'-Cartesian coordinate system in which the origin is kept fixed and the x' and y' axes are obtained by rotating the x and y axes counterclockwise through an angle \theta.
Rotational symmetry, also known as radial symmetry in biology, is the property a shape has when it looks the same after some rotation by a partial turn.
Rugby football refers to the team sports rugby league and rugby union.
Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter.
Science fiction (often shortened to Sci-Fi or SF) is a genre of speculative fiction, typically dealing with imaginative concepts such as advanced science and technology, spaceflight, time travel, and extraterrestrial life.
Scientific American (informally abbreviated SciAm) is an American popular science magazine.
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.
In geometry, the semidiameter or semi-diameter of a set of points may be one half of its diameter; or, sometimes, one half of its extent along a particular direction.
A sphere (from Greek σφαῖρα — sphaira, "globe, ball") is a perfectly round geometrical object in three-dimensional space that is the surface of a completely round ball (viz., analogous to the circular objects in two dimensions, where a "circle" circumscribes its "disk").
A spheroid, or ellipsoid of revolution, is a quadric surface obtained by rotating an ellipse about one of its principal axes; in other words, an ellipsoid with two equal semi-diameters.
In mathematics, a surface is a generalization of a plane which needs not be flat, that is, the curvature is not necessarily zero.
The surface area of a solid object is a measure of the total area that the surface of the object occupies.
Surface tension is the elastic tendency of a fluid surface which makes it acquire the least surface area possible.
The testicle or testis is the male reproductive gland in all animals, including humans.
Tethys (or Saturn III) is a mid-sized moon of Saturn about across.
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon and the Sun and the rotation of Earth.
In mathematics, a translation of axes in two dimensions is a mapping from an xy-Cartesian coordinate system to an x'y'-Cartesian coordinate system in which the x' axis is parallel to the x axis and k units away, and the y' axis is parallel to the y axis and h units away.
Uranus is the seventh planet from the Sun.
Volcanism is the phenomenon of eruption of molten rock (magma) onto the surface of the Earth or a solid-surface planet or moon, where lava, pyroclastics and volcanic gases erupt through a break in the surface called a vent.
The World Geodetic System (WGS) is a standard for use in cartography, geodesy, and satellite navigation including GPS.
Ellipsoid of revolution, Oblate ellipsoid, Oblate shape, Oblate sphere, Oblate spheroid, Oblateness Constant, Oblateness constant, Obloid, Prolate, Prolate spheroid, Sphereoid, Sphereoids, Spheroidal, Spheroids.