On a sphere of a radius R, the spherical area of a triangle Spherical Area =, where A, B and C are spherical angles of the triangle in radians and the value is called "the spherical excess of the triangle" (see the link http://mathworld.wolfram.com/SphericalTriangle.html ). So, from the given data, = = = 400.3185. Therefore, the radius of the sphere is about = 20 meters.