  The nuclear overlap zone in non-central relativistic heavy ion collisions is
azimuthally very asymmetric. By varying the angle between the axes of
deformation and the transverse direction of the pair momenta, the suppression
of $J/\Psi$ and $\Psi'$ will oscillate in a characteristic way. Whereas the
average suppression is mostly sensitive to the early and high density stages of
the collision, the amplitude is more sensitive to the late stages. This effect
provides additional information on the $J/\Psi$ suppression mechanisms such as
direct absorption on participating nucleons, comover absorption or formation of
a quark-gluon plasma. The behavior of the average $J/\Psi$ suppression and its
amplitude with centrality of the collisions is discussed for SPS, RHIC and LHC
energies with and without a phase transition.
