The Royal Astronomical Society is delighted to announce the winners of its prizes for the best PhD theses completed in the UK in 2025.
Prizes are awarded annually: the Michael Penston Prize for the best thesis in astronomy and astrophysics, the Keith Runcorn Prize for the best thesis in geophysics and planetary science, and the Patricia Tomkins Prize for the best thesis in instrumentation science for astronomy and geophysics.
The Michael Penston Thesis Prize 2025
The Michael Penston Thesis Prize 2025 has been awarded to Dr Thomas Baycroft for the thesis entitled 'Tools to detect and characterise circumbinary exoplanets'.
Dr Baycroft completed his PhD at the University of Birmingham, supervised by Professor Amaury Triaud. His thesis work was focussed on exoplanets that orbit a binary star, sometimes referred to as 'tatooines'. He utilised data from across multiple sources obtaining data from large telescopes in Chile and France as well as publicly available data from space telescopes.
Dr Baycroft is currently a T.D. Lee fellow at the Tsung-Dao Lee Institute of Shanghai Jiao Tong University, working on various aspects of exoplanet science with a focus on using the upcoming data release from ESA's Gaia telescope to understand the demographics of exoplanets.
He said: "I am honoured to receive this award from the Royal Astronomical Society. I'd like to thank my PhD supervisor Amaury Triaud for his guidance, as well as everyone at the University of Birmingham who made my time there so enjoyable and fun."
The runner-up for the Michael Penston Thesis Prize 2025 is Dr Emilie Hertig, of the University of Cambridge, with a thesis entitled 'Probes of cosmic inflation: from the CMB to quantum analogues'.
The panel also wished to publicly acknowledge three highly commended theses:
- Dr Martina Veresvarska (Durham University) – 'On the structure of accretion flows in compact accreting objects: A variability study across scales'
- Dr James Munday (University of Warwick) – 'The population of close double white dwarf binary stars'
- Dr Nathan Magnan (University of Cambridge) – 'Planet formation, resonant drag instabilities, and vortices'
The Patricia Tomkins Thesis Prize 2025
The winner of the Patricia Tomkins Thesis Prize 2025 is Dr Justin Tabbett with a thesis entitled 'Characterisation, Development and Deployment of a Balloon‑borne Radioactivity Detector'.
Dr Tabbett completed his PhD in Aerospace Engineering at the University of Bristol with Professor Karen Aplin. During his studies he worked on developing the microscintillator radioactivity detector, a project which was supported by A-Squared Technologies.
"I'm incredibly grateful to have won this award, and I'd particularly like to thank Professor Karen Aplin for her supervision during my PhD," Dr Tabbett said. "Also, to Alan and Kate at A-Squared for their support of my PhD!"
Currently, Dr Tabbett is a post-doctoral researcher at the Paul Scherrer Institute PSI in Switzerland, working within the Detectors, Irradiation and Applied Particle Physics group. His research continues to focus on the development and deployment of sophisticated atmospheric radiation instrumentation.
"I'm pleased to continue working on detectors, and I'm especially looking forward to our upcoming balloon flights! I particularly enjoy this research because it is so multi-disciplinary and offers many unique challenges to solve," he added.
"I hope to continue working on instrumentation and also get involved in teaching."
The Keith Runcorn Thesis Prize 2025
The winner of the Keith Runcorn Prize 2025 is Dr Hannah Sanderson for her PhD thesis titled 'Unlocking planetisimal histories using refined thermal evolution and dynamo generation models'.
"I'm honoured to have won this prize. I'm very grateful to my supervisors for supporting and challenging me to produce an excellent thesis and making my PhD so enjoyable," she said.
Dr Sanderson completed her PhD in the Earth Sciences department at the University of Oxford on planetesimal dynamo generation.
She is now a Postdoctoral Fellow at the Centre for Planetary Habitability at the University of Oslo, where she is researching the dynamics of metal-silicate separation in magma oceans and the implications for mantle redox evolution.
The runner-up for the Keith Runcorn Prize 2025 is Dr Joanna Egan, of the Open University, for her PhD thesis titled 'Optical properties of Venusian clouds'.
ENDS
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RAS Thesis Prize winners for 2025
Caption: From left, winner of the Michael Penston Thesis Prize for 2025 Dr Thomas Baycroft, winner of the Keith Runcorn Prize Dr Hannah Sanderson and winner of the Patricia Tomkins Thesis Prize Dr Justin Tabbett.
Credit: Supplied
Notes for editors
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