Life in the Cosmic Neighbourhood: Galactic Habitable Zones in the EAGLE Simulations

When and where is life most likely to form in the universe? We use the EAGLE cosmological hydrodynamical simulations to investigate the prevalence and properties of life-friendly cosmic environments on galactic scales. Our model for the occurrence of observers depends on main-sequence stars, the production and distribution of metals, and the formation of habitable planets. We also take into account five potentially life-extinguishing processes: core-collapse supernovae, Type Ia supernovae, star-star interactions, gamma ray bursts and quasars. We characterise the amount of time that the universe creates on habitable planets per unit mass of baryons and stars in the universe, as a function of galaxy mass and galactocentric distance. As expected, early universe, newly formed, high star formation rate galaxies are the most dangerous. The present-day Milky Way is typical of habitable galaxies: efficient creation of habitable time, and low probability of cosmic catastrophes.