  We examine the singularities of the wave fronts of null geodesics from point
sources in the Kerr Metric. We find that the wave fronts develop a tube like
structure that collapses non-symmetrically, leading to cusp features in the
wave front singularities. As the wave front advances, the cusps trace out an
astroidal shaped caustic tube, which had been discovered previously using lens
mapping and geodesic deviation methods. Thus, the wave front approach in this
study helps to complete a picture of caustics and gravitational lensing in the
Kerr geometry.
