I received my BSE degree in Mechanical and Aerospace Engineering from Princeton and MS and PhD in Aeronautics from Caltech. There, I did a minor in Planetary Science and was inspired by the likes of Andy Ingersol, Gene Shoemaker and Dave Stevenson. After a postdoc at Brown and a stint at Mitsubishi Heavy Industries, I came to UT in 1993. My PhD work involved molecular-based simulations of rarefied flow. At UT I followed up on an idea introduced by Ingersol concerning the rarefied supersonic winds on Io. I have simulated Io's sublimation and volcanic plume atmosphere since the late 1990s as a collaborative effort with Philip Varghese (ASE/EM) and Larry Trafton (Astro) and others outside of UT. I developed the idea of crashing a spacecraft into a lunar polar crater to look for water vapor in the debris plume for Lunar Prospector. As a group we have been continuing to model Io's atmosphere and aurora and have developed a sophisticated 3D global circulation model that includes a fair bit of physics. We are applying similar techniques to study comet and spacecraft impacts on the Moon and water geysers on Enceladus.