UCI seismologist Lisa Grant Ludwig is co-winner of NASA’s 2012 Software of the Year Award for her work on a program that models the behavior of earthquake faults to improve earthquake forecasting and our understanding of earthquake processes. QuakeSim, developed at NASA’s Jet Propulsion Laboratory, uses NASA remote sensing and other earthquake-related data to simulate and model the behavior of faults in three dimensions, both individually and as part of complex, interacting systems. This provides long-term histories of fault behavior that can be used for statistical evaluation. QuakeSim also is used to identify regions of increased earthquake probability, called hot spots. Studies have shown it to be the most accurate tool of its kind for intermediate earthquake forecasting and detecting the subtle, transient deformation in Earth’s crust that precedes and follows earthquakes. QuakeSim’s applications include scientific studies, developing earthquake hazard maps that can be used for targeted retrofitting of earthquake-vulnerable structures, providing input for damage and loss estimates after earthquakes, guiding disaster response efforts, and studying fluid changes in reservoirs. The award recognizes innovative software that significantly improves the agency’s exploration of space and maximizes scientific discovery on Earth.