Cool flames in an equimolar propane-oxygen premixture have been studied at reduced gravity in a closed, unstirred, static, spherical reactor. Acquired visual records were then analyzed and used to determine the cool flame propagation speeds for different vessel temperatures and initial reactant pressures. Without complexities associated with natural convection, transport is governed by diffusion of heat and species and the reactive-diffusive flame front as evidenced by the peak visible light emission, which is observed to propagate from the center of the reactor towards the walls. Flame speed dependencies on the flame radius, mixture composition, temperature, and pressure are presented. Additionally, the very nature of the propagation mechanism is brought into question as the flame propagation speeds are roughly an order of magnitude higher than the diffusional speeds based on a simple scaling analysis. Perhaps, the apparent front propagation is a phase wave with temperature and species concentration profiles altered by diffusion. A first comparison between these experimental results and the light emission predicted using a reduced propane mechanism, augmented with diffusive transport, by Fairlie and co-workers shows a much steeper light intensity gradient in the experiments than in the model.