Building Habitable Worlds

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The Solar System formed from the collapse of a molecular cloud of gas and dust ~4.6 billion years ago. But how did that gas and dust coalesce into the Sun and eight planets that we see today? What processes and events led to the formation of habitable planets like the Earth? And how do conditions at the birth of the Solar System compare to what we see in other planetary systems? I will answer these questions by studying meteorites and extraterrestrial samples returned by space missions, rocky time capsules that can be used to probe the earliest stages of Solar System formation and the evolution of planets.Water may have been delivered to habitable planets by asteroids. Two space missions, JAXA's Hayabusa2 and NASA's OSIRIS-REx, have successfully returned to Earth with samples of the water-rich asteroids Ryugu and Bennu, respectively. In addition, the fall of the Winchcombe meteorite provided the UK with complementary materials from the early Solar System. I will study the mineralogy and composition of Ryugu, Bennu, and fresh hydrated meteorites to understand the aqueous and thermal history of primitive water-rich asteroids and constrain the nature and distribution of volatiles in the protoplanetary disk.In the last decade new computer models and the detection of exoplanets have shown that planetary systems are dramatically shaped by giant planet migration. In the Solar System, the inward and outward movement of Jupiter and Saturn caused turbulence and widespread mixing of materials from the inner and outer regions of the protoplanetary disk. I will use hypervelocity impact experiments to reproduce this mixing and determine how much water was retained in planetary surfaces following asteroid impacts.Some meteorites come from asteroids that have remained dormant throughout their history and preserve minerals that were once swirling around the newly forming Sun. I will investigate presolar grains that condensed around ancient stars to understand their role in the formation and evolution of organic matter in interstellar space and the first stages of accretion within the Solar System.