ABSTRACT:
Dark matter halos are the fundamental unit of structure formation and they provide the framework for our modern understanding of galaxy formation. I will discuss new limits on the connection between galaxy properties and their dark matter hosts over a range of masses and redshifts. In the context of a given cosmological model, I will show how the galaxy-halo relation can be tightly constrained at low redshift, and how the galaxy-halo connection can be used to infer the full star formation histories of galaxies. This model, based on LCDM halos, is in excellent agreement with a wide range of data, including the statistics of Magellanic Cloud mass satellites around Milky Way mass hosts. I will discuss new limits on the number of satellites the luminosity of Fornax around such hosts; in this regime there is still considerable degeneracy between the galaxy-halo connection and the properties of dark matter.