How long does it take for photons to travel through clouds of particles in the air? Sandia researchers utilized a new photon propagation simulation tool based on the open-source Physically Based Rendering Toolkit software and compared its results to measurements taken in a well-characterized fog chamber. The findings showed that the simulation and measurements agreed within their uncertainties, providing confidence in the model.
This work produced tangible data, demonstrating that the new model can accurately simulate real-world photon transport. As a result, the team drastically reduced the risk in using these models in applied research. The implications of this research extend to mission areas such as storm lightning signal prediction, long-distance optical data transmission through air, and directed energy applications. Looking ahead, Sandia plans follow-on projects, including a study of cloud-top light dispersion as observed by space-based sensors using laboratory experiments and the new simulation tool.
Cool fact > This work confirmed that the travel time of photons can be predicted reliably.
Sandia experts linked to work
- Adam Les Hammond-Clements
July 14, 2025