  The damping of high momentum excitations in strongly coupled maximally
supersymmetric Yang-Mills plasma is studied. Previous calculations of the
asymptotic behavior of the quasinormal mode spectrum are extended and
clarified. We confirm that subleading corrections to the lightlike dispersion
relation $\omega({\bf q}) = |{\bf q}|$ have a universal $|{\bf q}|^{-1/3}$
form. Sufficiently narrow, weak planar shocks may be viewed as coherent
superpositions of short wavelength quasinormal modes. The attenuation and
evolution in profile of narrow planar shocks are examined as an application of
our results.
