Covering the sphere with 11 equal circles (Q1079821)

The problem of thinnest spherical circle-covering consists of the determination of the smallest angular radius \(r_ n\) of n equal spherical caps by which the surface of a sphere can be covered without gaps. This problem has been solved so far only for a few integers n, the first gap in the sequence of the cases settled being at \(n=11\). In this paper two configurations for covering the sphere with 11 equal circles are described, the first having the radius \(r_{11}=41\circ 29'28.0''\), the second \(r_{11}=41\circ 25'37.9''\).