Astrobiology PhD Projects
Research projects on offer in our Astrobiology group
Modelling prebiotic chemistry in Early Earth and Exoplanet atmospheres
Laboratory studies have shown that organic molecules that form the building blocks of life, e.g., precursors to amino acids, lipids, and nucleosides, can be synthesised from feedstocks of comparatively simple molecules such as hydrogen cyanide (HCN) and its derivatives.
In this project, we will use the Met Office climate model to describe plausible prebiotic environmental conditions on Early Earth and tidally locked rocky exoplanets.
The initial chemical network will be informed by a growing number of theoretical studies that are progressively fleshing out HCN chemistry towards the explicit formation of more complex organic molecules.
We will work closely with laboratory groups that are developing different parts of the HCN chemistry network.
We will explore the sensitivity of atmospheric chemistry to being irradiated by different stars, e.g., a young Sun and a M dwarf, and the location of the planet within the circumstellar habitable zone.
For the rocky exoplanet, guided by 1-D model calculations, we will also the investigate the sensitivity of HCN chemistry to the ratio of carbon to oxygen. Using a global 3-D climate model offers an opportunity to identify potential surface aqueous environment niches across the planet that preferentially support atmospheric HCN chemistry, from which some of the chemical products could be lofted to the atmosphere to help form complex organic molecules.
The model can also be used to explore hypothetical atmospheric sources of HCN, e.g., meteoritic bombardment and lightning, and the processes that would be necessary for the subsequent atmospheric formation of more complex organic molecules.
Requirements:
The successful candidate will have a degree in the physical sciences and most likely physics, chemistry, or applied mathematics.
This is a computational and data analysis project: no prior computing experience is necessary, but some knowledge of coding would be useful (e.g., Python, FORTRAN)
References:
Lightning-induced chemistry on tidally-locked Earth-like exoplanets https://doi.org/10.1093/mnras/stac2722
A consistent reduced network for HCN chemistry in Early Earth and Titan atmospheres: quantum calculations of reaction rate coefficients https://doi.org/10.1021/acs.jpca.8b11323
Hydrogen cyanide in nitrogen-rich atmospheres of rocky exoplanets https://doi.org/10.1016/j.icarus.2019.02.020
Common origins of RNA, protein and lipid precursors in a cyanosulfidic protometabolism https://www.nature.com/articles/nchem.2202
Creation and evolution of impact-generated reduced atmospheres of early Earth https://iopscience.iop.org/article/10.3847/PSJ/ab7e2c