Planetary Science at Bristol

布里斯托尔的行星科学

• 批准号: ST/V000888/1
• 负责人: Timothy Elliott
• 金额: $ 66.1万
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FV000888%2F1
• 关键词: Planetary; Science; Bristol

We will make a timely return to a legacy of the manned Apollo 12-16 missions to the moon: an extensive seismic dataset. This dataset recorded of over 12500 'moonquakes' has been used extensively to image the deep structure of the moon, but these studies only provide a static picture. Seismic anisotropy enables us to probe subsurface dynamics, but its measurement is challenging for the complex lunar data. Recent advances in analysis techniques developed for noisy terrestrial data now make these measurements possible. Such measurements can be used to probe processes such as convection in the lunar mantle, or even tell whether there are still hot, molten traces of the moon's fiery birth deep in the interior.Unlike the Earth's moon, Saturn's giant moon Titan, has a thick atmosphere with an exotic mix of nitriles and hydrocarbons. Titan provides a natural laboratory to test our understanding of atmospheric chemistry and physics. There are also many similarities with Earth including polar vortices and distinct polar chemical compositions, that can provide insight into our own planet. A wealth of data from the Cassini spacecraft and the James Webb Space Telescope, will be used to study Titan's atmosphere. In particular we will examine the role of atmospheric waves, extreme cold and polar feedbacks, and orbital influences on Titan's seasons. As well as the large moons, we will also study small, asteroid bodies. In particular, we will attempt to explain surface features discovered on high definition images obtained by recent missios. We seek to explain 'lowland' topography. The goal of this research is to understand how changes in shape, spin-period, and overall size of the asteroid influence the formation of lowlands, to assist in the selection of future targets for sample return missions. Vaporisation occurs when planetary objects collide, as an inevitable part of their growth in the gas-dust disk around the proto-Sun. Yet it was previously assumed that the less volatile major building blocks, silicon and magnesium (1/3 Earth's mass) were unaffected. New measurements from our group suggest ~50% of Earth's original mass was vaporised, challenging this paradigm. However, there are no experimental data to substantiate the importance of vapour loss in shaping planetary compositions. We propose innovative experiments and analysis to determine the necessary liquid-vapour chemical interactions and address this knowledge gap, allowing us to better model planetary forming processes.Water is vital to understanding the formation and habitability of terrestrial planets. At the birth of the Solar System small planetary bodies formed through the accretion of dust, mineral grains and sometimes ice. The addition of water and other volatile elements to these small planetary bodies may have taken place in the inner Solar System asteroid belt or near Saturn and Jupiter's orbit. Distinguishing between these scenarios is critical for models of planetary growth. Some meteorites contain small amounts of water trapped in minerals over this long time period. In this project we will analyse the isotopic composition of this water to fingerprint to where in the Solar System it was added. A prime constituent of many asteroids and meteorites are millimetre sized, quenched melt droplets or chondrules. These objects formed in the first few million years of solar system history, although exactly when is a matter of considerable debate. It is a challenging problem as we need to distinguish time periods of less than 1million years in objects more than 4.5 billion years old. Yet it is important problem to be able to reliably map the formation of chondrules on the appropriate time period in a rapidly evolving early solar system. We will apply a novel dating approach we have developed as part of previous STFC funding to hopefully reconcile currently contrasting interpretations.

我们将及时返回阿波罗12-16载人登月任务的遗产：广泛的地震数据集。这个记录了12500多次月震的数据集被广泛用于拍摄月球深层结构的图像，但这些研究只提供了一张静态图像。地震各向异性使我们能够探测地下动力学，但它的测量对于复杂的月球数据是具有挑战性的。最近为噪声地面数据开发的分析技术的进步使这些测量成为可能。这样的测量可以用来探测月球地幔对流等过程，甚至可以判断月球内部深处是否仍有炽热、熔融的月球诞生的痕迹。与地球的月球不同，土星的巨型卫星土卫六拥有厚厚的大气层，含有稀有的氰化物和碳氢化合物。土卫六提供了一个天然的实验室来测试我们对大气化学和物理的理解。与地球也有许多相似之处，包括极地涡旋和不同的极地化学成分，这可以提供对我们自己星球的洞察。来自卡西尼号宇宙飞船和詹姆斯·韦伯太空望远镜的大量数据将被用于研究土卫六的大气。特别是，我们将研究大气波动、极端寒冷和极地反馈以及轨道对土卫六季节的影响。除了大卫星，我们还将研究小型小行星。特别是，我们将试图解释在最近的MISTOS获得的高清晰度图像上发现的地表特征。我们试图解释“低地”地形。这项研究的目的是了解小行星的形状、自转周期和总体大小的变化如何影响低地的形成，以帮助选择未来的目标进行样本返回任务。当行星物体相撞时，就会发生汽化，这是它们在原太阳周围的气体尘埃盘中生长的必然部分。然而，之前的假设是，挥发性较小的主要组成部分--硅和镁(占地球质量的三分之一)不会受到影响。我们小组的新测量表明，地球原始质量的约50%被蒸发，挑战了这一范式。然而，没有实验数据证实水蒸气损失在塑造行星组成方面的重要性。我们提出了创新性的实验和分析，以确定必要的液体-蒸汽化学相互作用，并解决这一知识差距，使我们能够更好地模拟行星形成过程。水对于理解类地行星的形成和宜居性至关重要。在太阳系诞生之初，由尘埃、矿物颗粒，有时还有冰的吸积而形成的小行星。水和其他挥发性元素添加到这些小行星中可能发生在内太阳系小行星带或土星和木星轨道附近。区分这些情景对于行星增长模型至关重要。一些陨石含有少量的水，在很长一段时间内被困在矿物中。在这个项目中，我们将分析这些水的同位素组成，以确定它在太阳系中添加的位置。许多小行星和陨石的主要成分是毫米大小的淬火熔滴或球粒。这些天体形成于太阳系历史的最初几百万年，尽管确切的时间是一个相当大的争论问题。这是一个具有挑战性的问题，因为我们需要区分超过45亿年的物体中不到100万年的时间段。然而，在一个快速演化的早期太阳系中，能够在适当的时间段可靠地绘制球粒陨石的形成图是一个重要的问题。我们将应用我们开发的一种新的约会方法，作为之前STFC资金的一部分，希望能协调目前不同的解释。

项目成果

The formation and aqueous alteration of CM2 chondrites and their relationship to CO3 chondrites: A fresh isotopic (O, Cd, Cr, Si, Te, Ti, and Zn) perspective from the Winchcombe CM2 fall

CM2 球粒陨石的形成和水蚀变及其与 CO3 球粒陨石的关系：来自 Winchcombe CM2 陨石坑的新鲜同位素（O、Cd、Cr、Si、Te、Ti 和 Zn）视角

• DOI: 10.1111/maps.13968
• 发表时间: 2023
• 期刊: Meteoritics & Planetary Science
• 影响因子: 2.2
• 作者: Greenwood R

The Winchcombe meteorite, a unique and pristine witness from the outer solar system.

• DOI: 10.1126/sciadv.abq3925
• 发表时间: 2022-11-18
• 期刊: Science advances
• 影响因子: 13.6

Planetary accretion and core formation inferred from Ni isotopes in enstatite meteorites

从顽辉石陨石中的镍同位素推断行星吸积和核心形成

• DOI: 10.7185/geochemlet.2306
• 发表时间: 2023
• 期刊: Geochemical Perspectives Letters
• 影响因子: 4.9
• 作者: Zhu K

Calcium Isotope Evolution During Differentiation of Vesta and Calcium Isotopic Heterogeneities in the Inner Solar System

• DOI: 10.1029/2022gl102179
• 发表时间: 2023-02
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Ke Zhu;Hejiu Hui;M. Klaver;Shiying Li;Lu Chen;W. Hsu

Radiogenic chromium isotope evidence for the earliest planetary volcanism and crust formation in the solar system

• DOI: 10.1093/mnrasl/slac061
• 发表时间: 2022-07
• 期刊: Monthly Notices of the Royal Astronomical Society: Letters
• 作者: K. Zhu;H. Becker;Shijin Li;Yan Fan;Xiao-Ning Liu;T. Elliott