  The structure of a light cone in the Goedel universe is studied. We derive
the intrinsic cone metric, calculate the rotation coefficients of the ray
congruence forming the cone, determine local differential invariants up to
second order, describe the crossover (keel) singularities and give a first
discussion of its focal points. Contrary to many rotation coefficients, some
inner differential invariants attain simple finite standard values at focal
singularities.
