A Grand-Challenge Galaxy Simulation

Recent years have witnessed enormous gains in the complexity of numerical astrophysics simulations, and the compuational power of the machines that run them. Only a few decades ago, models of galaxy formation and evolution relied on calculations with a few million cells or particles -- now those numbers typically exceed billions. With the advent of modern, GPU-based machines, such as the exascale-breaking Frontier at Oak Ridge National Lab, a new opportunity arises to increase the resolution by orders-of-magnitude more... provided the software algorithms can keep up. In this talk, I will describe our work to prepare the astrophysics code Cholla to run a "grand challenge" trillion-cell galaxy simulation on Frontier. With a domain resolution of 10,000³ cells, this simulation will be the first to capture the cycle of star formation, supernova explosions, and galaxy outflows on the scale of our own Milky Way galaxy. The simulation will additionally produce hundreds of terabytes of data to be compared with the most detailed surveys available. Combining these results promises to help us answer fundamental questions about how galaxies form, grow, and evolve throughout cosmic history.