We report on the experimental performance of a solar aerosol reactor for carrying out the combined thermochemical reduction of CeO2 and reforming of CH4 using concentrated radiation as the source of process heat. The 2 kW(th) solar reactor prototype utilizes a cavity receiver enclosing a vertical Al2O3 tube which contains a downward gravity-driven particle flow of ceria particles, either co-current or counter-current to a CH4 flow. Experimentation under a peak radiative flux of 2264 suns yielded methane conversions up to 89% at 1300 degrees C for residence times under 1 s. The maximum extent of ceria reduction, given by the nonstoichiometry 5 (CeO2-delta), was 0.25. The solar-to-fuel energy conversion efficiency reached 12%. The syngas produced had a H-2:CO molar ratio of 2, and its calorific value was solar-upgraded by 24% over that of the CH4 reformed.