Hugh O'Neill is an earth scientist whose career has focused on experimental petrology and geochemistry - the study of the composition of rocks, their minerals, and how they came to form. His work has been crucial in advancing our understanding of how rocky planets form, and how the detailed study of Earth materials can solve large-scale geological problems.

He has greatly improved our understanding of key questions relating to our planet, including: the chemical composition of Earth and how it differs from other planets; the origin of the Moon; and the history of Earth. His work stands out due to his use of careful laboratory measurements to address big problems.

Hugh is an Australian Research Council Laureate Fellow at the Research School of Earth Sciences (RSES), the Australian National University - one of the foremost research groups worldwide concerning experimental investigation into deep Earth petrology. As well as being a Fellow of the Royal Society, he is a Fellow of the Mineralogical Society of America, the Geochemical Society and the Australian Academy of Sciences.