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A unit of measure of solid angles. Formally, it is the angle subtended at the center of the sphere by a portion of the surface whose area is equal to the square of the radius of the sphere. There are 4 pi steradians in a sphere.
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the standard unit of solid angle measure in mathematics. Just as there are 2 pi radians in a circle, there are 4 pi steradians in a sphere. Thus one steradian equals about 0.079 577 sphere. There are 129 600/ pi = 41 252.96 square degrees in a sphere, so 1 steradian also equals about 3282.806 square degrees. The unit originated in the 1870s by analogy with the radian.
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(str) A solid angle with vertex at the center of a sphere of radius r that encompasses an area of r2 on the surface of the sphere.
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The unit of measure for a solid angle.
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the unit of solid angle adopted under the Systeme International d'Unites
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a conical figure, or solid angle, whose intersection with a unit sphere covers one unit area
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a measure of solid angle, in the same way that a radian measures angles
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a solid angle at the centre of sphere of one metre radius that is subtended by one square metre of the surface
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a unit area of a spherical surface with a unit radius
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A steradian is defined as the solid (spatial) angle which, having its vertex at the center of the sphere, cuts off an area equal to the square of its radius. So, 1 steradian has a projected area of 1 square meter at a distance of 1 meter, etc. A sphere contains 4*pi steradians.
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The solid angle that cuts unit area from the surface of a sphere of unit radius centred at the vertex of the solid angle. There are 4(pi )sr in a sphere.
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The solid angle subtended at the center of a sphere by an area on the surface of the sphere equal to the square of the sphere radius.
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Unit of solid angle. An entire sphere has 4B steradians.
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Solid angle subtending an area on the surface of a sphere equal to the square of the radius. There is 4n steradian in a sphere.
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A unit solid angle on the surface of a sphere equal to the square of the sphere's radius.
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Steradian is the solid angle that, having its vertex in the center of a sphere, cuts off an area of the surface of the sphere equal to that of a square with sides of length equal to the radius of the sphere.
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the unit of solid angle. There are 4*pi steradians in the entire celestial sphere. One square degree is (1/57.3)2 steradians because one degree is (1/57.3) radians.
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The unit of measure of solid angles, equal to the angle subtended at the center of a sphere.
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A unit of solid angle. A complete sphere subtends 4 steradians from the centre.
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The steradian (symbol: sr) is the SI unit of solid angle. It is used to describe two-dimensional angular spans in three-dimensional space, analogous to the way in which the radian describes angles in a plane. The name is partly derived from the Greek stereos for "solid".
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