  We calculate photon production from a quark-gluon plasma which is anisotropic
in momentum space including the Compton scattering and quark/anti-quark
annihilation processes. We show that for a quark-gluon plasma which has an
oblate momentum-space anisotropy the photon production rate has an angular
dependence which is peaked transverse to the beam line. We propose to use the
angular dependence of high-energy medium photon production to experimentally
determine the degree of momentum-space isotropy of a quark-gluon plasma
produced in relativistic heavy-ion collisions.
