research Galaxy Formation Simulating how galaxies form and evolve across cosmic time The Circumgalactic & Intergalactic Medium The gas that fuels and regulates galaxy growth The First Stars The formation of the first luminous objects in the universe X-ray Clusters The most massive collapsed structures in the universe Machine Learning & AI Connecting simulations to observations with machine learning and simulation-based inference Learning the Universe Simons Collaboration — inferring the universe's initial conditions with simulation-based inference software Enzo & Enzo-E Open-source adaptive mesh refinement codes for astrophysics Grackle A chemistry and radiative cooling library for astrophysical simulations