Planetary Science Group, Department of Earth and Planetary Sciences, Birkbeck, University of London: Consolidated Grant Proposal

这项综合拨款的申请是为了支持伦敦大学伯克贝克的行星科学研究。伯克贝克的地球和行星科学系拥有一个相对较小但非常活跃的行星科学研究小组，主要从事月球和火星研究、结冰卫星、流星学和天体生物学。在过去的五年里，我们的团队在国际行星科学文献中领导(即第一作者)了25篇同行评议论文，做出了重大贡献(即共同撰写)了另外58篇同行评议出版物，并在国际会议上提交了70多篇扩展摘要。本申请旨在通过在四个行星科学项目上为3个PDRA和1个博士生提供支持来推进我们在这些领域的工作，具体如下：(1)“限制月球陨石的来源位置”。我们希望将之前授予的为期三年的博士学位延长六个月，以最大限度地提高科学产出，并利用与项目(2)的协同效应。(2)“确定火星陨石的来源位置”。对火星的探索是试图了解行星系统如何进化以及生命是否为地球独有的尝试的核心。火星陨石目前是唯一可供研究的火星样本，并提供了对火星地壳地球化学的详细了解。然而，这些陨石从未在地球化学上与火星上的源头位置联系在一起，这意味着它们的地质背景缺失，从它们收集的信息不能自信地用于地质和天体生物进化的研究。该项目的目的是通过将火星陨石的组成知识与火星表面的高光谱数据相结合，将火星陨石的地球化学分析与火星的地质演化联系起来，以确定陨石的来源位置。(3)“水星：制约其内部分化和化学演化的因素。”水星是地球上最不为人所知的行星，就其密度和与太阳的距离而言，水星是行星的终极成员。因此，它对行星的形成和演化提供了重要的约束。为了更好地约束汞的合适构造块并限制其热化学演化，我们的目标是：(A)进行一系列系统的实验，以研究与汞内部相关的条件下微量元素在固体和液体矿物相之间的分配行为；(B)对被认为是汞构造块的EH和CB球粒陨石进行详细分析；以及(C)根据基于球粒陨石结果的水银地幔成分的部分熔体的主要元素组成，模拟水星地幔的分离结晶趋势。(4)在地球上的类似物的引导下，探测火星上的生命生物特征。识别火星上过去或现在的生命的关键是对保存生物特征的地质能力和环境退化影响的综合了解。在跨学科专业知识的基础上，这项研究将结合实验模拟、野外工作和光谱分析，创造一种地质学和生物学方法的综合，从而能够在火星上进行生物特征检测。主要目标是：(A)确定来自几个不同的火星模拟环境的岩石中的特征光谱生物特征；(B)编制现有生命的红外光谱生物特征目录；(C)量化地质材料中暴露在火星紫外线辐射下的生物特征的光谱变化。这些结果将为未来的火星探索活动提供信息，并将有助于解释欧空局将在该项目结束时发射的ExoMars月球车收集的数据。

This application for a Consolidated Grant is to support planetary science research at Birkbeck, University of London. The Department of Earth and Planetary Sciences at Birkbeck hosts a relatively small, but very active, planetary science research group, specialising principally in lunar and Mars research, icy satellites, meteoritics, and astrobiology. Over the last five years our group has led (i.e. has first-authorship of) 25 peer reviewed papers in the international planetary science literature, has made significant contributions (i.e. co-authorship of) 58 additional peer reviewed publications, and contributed over 70 extended abstracts presented at international conferences. The present application is intended to advance our work in these areas by providing support for 3 PDRAs and one PhD student on four planetary science projects, as follows:(1) "Constraining the source localities of lunar meteorites." We wish to extend this previously awarded three-year PhD studentship by six months to maximise scientific output and exploit synergies with Project (2).(2) "Determining the Source Locations of Martian Meteorites." The exploration of Mars lies at the heart of the attempt to understand how planetary systems evolve and whether life is unique to Earth. Martian meteorites currently represent the only samples of Mars available for study and have provide a detailed understanding of the geochemistry of the martian crust. However, these meteorites have never been geochemically tied to source locations on Mars, meaning that their geological context is missing and that the information gleaned from them cannot confidently be used in studies of the geological and astrobiological evolution. The aim of this project is to link the geochemical analyses of martian meteorites to the geological evolution of Mars by combining a knowledge of the composition of martian meteorites with hyperspectral data of the surface of Mars to determine the source locations of the meteorites. (3) "Mercury: Constraints on its internal differentiation and chemical evolution." Mercury is the least well-known terrestrial planet and represents a planetary end-member with respect to its density and proximity to the Sun. It thus provides important constraints on planetary formation and evolution. In order to provide better constraints on suitable building blocks for Mercury and to constrain its thermo-chemical evolution, we aim to: (a) conduct a systematic set of experiments to investigate the partitioning behaviour of trace elements between solid and liquid mineral phases under conditions relevant to the interior of Mercury; (b) conduct detailed analysis of EH and CB chondrites that have been proposed to be the building blocks for Mercury; and (c) model the fractional crystallization trends for the Mercurian mantle based on the major element compositions of partial melts of the Mercurian mantle composition based on the chondrite results.(4) "Detection of life's biosignatures on Mars guided by Earth-based analogues." The key to identifying past or present life on Mars is an integrated understanding of the geological capabilities for the preservation of biosignatures and the degenerative effects of the environment. Building on cross-disciplinary expertise, this study will combine experimental simulations, fieldwork, and spectroscopic analyses to create a synthesis of geological and biological methods to enable biosignature detection on Mars. The main objectives are to (a) identify characteristic spectroscopic biosignatures in rocks from several distinct Mars analogue environments; (b) catalogue the IR spectroscopic biosignatures of extant life; and (c) quantify the spectral modification of biosignatures within geological materials after exposure to martian UV radiation. The results will inform future Mars exploration activities, and will aid in the interpretation of data collected by ESA's ExoMars rover to be launched towards the end of the Project.