The cosine formula from spherical trigonometry gives the angular separation between two points on the surface of a sphere, where the apex of the angle is at the center of the sphere. If the two points...The cosine formula from spherical trigonometry gives the angular separation between two points on the surface of a sphere, where the apex of the angle is at the center of the sphere. If the two points have latitudes \phi_{1} and \phi_{2} and longitudes L_{1} and L_{2}, then the cosine formula gives the angular separation of the two points \theta :
