Speaker: Prof. Jon Wade, Department of Earth Sciences, University of Oxford Title: The irony of planetary habitability Abstract: Planetary habitability – how conducive a planet is to both support and initiate life – has often been interpreted as whether a planet can support liquid water on its surface, and hence its distance from the parent star.  However, we show that the abundance of iron in the planet’s rocky portion, and its bioavailability through geological time, is crucial to planetary habitability. Synthesised at the end of a star’s life, most of our planet’s iron resides in its metallic core, which inContinue reading

Speaker: Claire Guimond, Department of Earth Sciences, Cambridge University Title: Marble planet propensity: Insights from fundamental geophysics Abstract: Undetectable differences in how water is distributed on rocky planets will make or break whether they could support dry land, with big consequences for long-term climate stability and the chemical origin of life. Our sample of one marbled world reveals little about the cosmic probability of this planetary form. Indeed, Earth's land/ocean fraction reflects complex, indeterministic systems tied to its particular tectonic regime. Nevertheless, we can identify more intrinsic processes which promote land or oceans on any rocky planet, and which clue usContinue reading

Speaker: Dr. Yoshinori Miyazaki, Caltech Center for Comparative Planetary Evolution, California Institute of Technology Title: Volatile degassing from the planetary interior and its implication for habitability Abstract: A large amount of volatiles could be stored in the planetary interior, and volatile partitioning between the surface and interior plays a crucial role in characterizing planetary habitability. In this talk, I will consider the geodynamics and mantle degassing during the early stage of planetary evolution, from a magma ocean to the subsequent subsolidus convection stage, to understand how the surface volatile budget is determined on terrestrial planets. We find that, under stagnant-lidContinue reading