…an angle formed by the intersection of two great circles of a sphere…
…a triangle formed by three arcs of great circles on a sphere…
…a loss of definition in the image arising from the surface geometry of a spherical mirror or lens…
…three coordinates that define the location of a point in three-dimensional space. They are the length of its radius vector r, the angle θ between the vertical plane containing this vector and the x-axis, and the angle φ between this vector and the horizontal x-y plane…
…the branch of trigonometry concerned with the measurement of the angles and sides of spherical triangles…
…three coordinates that define the location of a point in three-dimensional space. They are the length of its radius vector r, the angle θ between the vertical plane containing this vector and the x-axis, and the angle φ between this vector and the horizontal x-y plane…
