Building Habitable Worlds

太阳系是由46亿年前由气体和尘埃组成的分子云坍塌形成的。但这些气体和尘埃是如何融合成我们今天所看到的太阳和八颗行星的呢？是什么过程和事件导致了像地球这样的宜居行星的形成？太阳系诞生时的情况与我们在其他行星系统中看到的情况相比如何？我将通过研究陨石和太空任务返回的外星样本来回答这些问题，这些陨石时间胶囊可以用来探测太阳系形成的早期阶段和行星的演化。水可能是由小行星输送到宜居行星上的。日本宇宙航空研究开发机构的Hayabusa2和NASA的OSIRIS-Rex两次太空任务分别成功地带着富含水的小行星Ryugu和Bennu的样本返回地球。此外，温奇科姆陨石的陨落为英国提供了来自早期太阳系的补充物质。我将研究Ryugu、Bennu和新鲜的水合陨石的矿物学和成分，以了解原始富水小行星的水和热历史，并限制原始行星盘中挥发物的性质和分布。在过去的十年里，新的计算机模型和对系外行星的探测表明，行星系统受到巨大行星迁移的戏剧性影响。在太阳系中，木星和土星的向内和向外运动导致了原行星盘内外区域的物质的湍流和广泛的混合。我将使用超高速撞击实验来再现这种混合，并确定小行星撞击后行星表面保留了多少水。一些陨石来自小行星，这些小行星在其历史上一直处于休眠状态，并保存了曾经围绕新形成的太阳旋转的矿物。我将研究凝聚在古老恒星周围的太阳系前颗粒，以了解它们在星际空间有机物质的形成和演化以及太阳系内吸积的第一阶段中所扮演的角色。

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.