Direct Photons at RHIC The most direct probe of the QGP is arguably the radiation of thermal photons, emerging directly from the thermalized system and providing, in principle, the temperature in its hottest phases. However, photons are largely produced in pi0 and eta decays, as well as in QCD annihilation and Compton processes that occur before thermalization. Thermally produced photons must be distinguished from those produced primordially in QCD interactions and those from final state decays of hadrons. Thus, as a first step, it is necessary to determine the yield of photons that are produced in excess of the photons from known hadronic decay sources. The PHENIX experiment has made measurements of direct photons in 200 GeV Au+Au collisions and p+p collisions. The fraction of photons due to direct production will be shown as a function of pT and centrality. This measurement will be compared to expectation from pQCD calculations.