ITC Colloquium

The first stars formed a few hundred million years after the Big Bang, starting the transition from the Dark Ages to Recombination. They are out of reach from current and planned facilities, and we rely on numerical methods to understand their properties. In this talk, I will focus on the galaxies that the first stars formed in: minihalos. Two large-scale effects -- Lyman-Werner radiation and streaming velocities -- affect these formation regions. With my large cosmological, hydrodynamical simulations, I have shown that both effects inhibit Pop III star formation in the low-mass end of the halo mass function, and that the two effects compound on each other. I will expand on the physical properties of these minihalos and conclude my talk with an outlook on how they might be observed with an ``Ultimately Large Telescope'' in the far future.