Mineral physics of icy planetary bodies
Lead Research Organisation:
University College London
Department Name: Earth Sciences
Abstract
The outer solar system contains a large number of ice-rich objects, ranging in size from a few km to a few thousand km across; the latter includes the Jovian satellites Ganymede and Callisto and the Saturnian moon Titan, each of which are larger than the planet Mercury. It has been recognised for many decades that the 'ice' portion of these large icy bodies will have inherited additional volatile and non-volatile constituents from their 'dirty snowball' accretionary precursors and will also have undergone substantial hydrothermal processing during core differentiation. The result of this is that the 'ice' layers will contain a range of hydrate compounds as 'rock-forming minerals'. However, it is only in the last 20 years that experimental and computational mineral physics methods have provided the tools to determine the behaviour of these materials under the relevant conditions of pressure and temperature (0 < P < 5 GPa, 100 < T < 400 K). Such work is essential to ensure an accurate basis for structural and evolutionary modelling, which in turn provides the means of interpreting observational data from remote and in situ planetary exploration.The aim of this studentship is to address long-standing problems in the structure and properties of high-pressure hydrate minerals, synthesising and recovering high-P polymorphs or dissociation products of materials such as meridianiite (MgSO4.11H2O), mirabilite (Na2SO4.10H2O), ammonia dihydrate (NH3.2H2O) and various sulfuric acid hydrates (H2SO4.nH2O).
Organisations
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| ST/R50516X/1 | 01/10/2017 | 30/09/2021 | |||
| 1924469 | Studentship | ST/R50516X/1 | 01/10/2017 | 30/09/2021 | Geoffrey Baron |
| Description | This work has successfully obtained accurate and precise measurements for the structures of the following high-pressure phases of ice, namely II, III, V, VI which were recovered to atmospheric pressure and measured at 10 K. These will be useful for computer models which aim to simulate the internal geophysics of icy moons in the solar system. The expansion coefficients of these ices have also been measured over a limited temperature range of 10-150 K. An investigation into the volume isotope effect (VIE), where the lighter hydrogen atoms in these ices are replaced by deuterium has found that all behave in a normal manner, unlike water-ice which has an anomalous VIE with the volume of the deuterated ice being the greater. The ices II, IX and XI were also successfully simulated using computations based on quantum mechanics. |
| Exploitation Route | The results could be used by those scientists interested in studying the moons of the outer solar system and in particular those connected with the ESA Jupiter Icy Moons Explorer mission and the NASA Juno space mission. |
| Sectors | Other |
| Description | London Science museum public engagements. |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Public/other audiences |
| Results and Impact | A series of talks about space science and climate change loosely connected to my research. This is an ongoing commitment. |
| Year(s) Of Engagement Activity | 2022 |
| Description | Public Talks |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Public/other audiences |
| Results and Impact | Short talks at the science museum in London on topics related to my research given to the general public. |
| Year(s) Of Engagement Activity | 2019 |
| Description | School Visit |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Schools |
| Results and Impact | General interest background to my research activities as part of a discussion about science. |
| Year(s) Of Engagement Activity | 2019,2020 |
| Description | School Visit ( West London) |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Schools |
| Results and Impact | The activity was to describe how we were able to understand the structure of the mantle and inner core of the Earth and the science that enabled this. |
| Year(s) Of Engagement Activity | 2021 |
| Description | School Visit Hanwell |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Schools |
| Results and Impact | Talk about my research in Earth Sciences and also how science is portrayed by media. |
| Year(s) Of Engagement Activity | 2022 |