Chao-Chin Yang, Zhaohuan Zhu, Stephen Lepp, and Xiao Hu (all Physics and Astronomy) just were awarded a $474,315 research grant by NASA through the Astrophysics Theory Program. They will conduct state-of-the-art computer simulations to model a circumstellar disk around a young star and study the dust-gas dynamics in the disk. The investigation will help us understand the variety of morphological features such as rings and gaps in nearby circumstellar disks detected recently by high-resolution, high-contrast observations. It will also improve the understanding of the process of planet formation. Zhu and Lepp are co-investigators on the project, and Hu is a collaborator.