In studies originally scheduled to begin Oct. 8 aboard the spaceshuttle Columbia, a team of scientists hopes to shed light on some ofthe mysteries of fire -- perhaps humankind's oldest yet least understood tool. Through experiments on large drops of liquid fuel, UC Davis combustion researcher Benjamin Shaw and his colleagues will be working to increase understanding of what happens when liquid fuel burns. Eventually, their studies may help increase fuel efficiency while lowering pollution and lead to better ways of extinguishing flames, including fires in the near-zero gravity of outer space. For the researchers, burning fuels in space like this removes perhaps the most confounding and frustrating variable in flame studies -- gravity, according to Shaw, an associate professor of mechanical and aeronautical engineering. In particular, Shaw will study diffusion of two fuels in a single burning drop. Led by Forman Williams, director of the UC San Diego Center for Energy and Combustion Research, the team will conduct combustion tests in a small "glove box" housed in the shuttle's microgravity laboratory. Via a color video camera, researchers will be able to monitor the results of the experiment.