As well as being a Research Fellow at St John's College, I am a Professor of Astrophysics. In 2005, I won a Philip Leverhulme Prize in Astronomy & Astrophysics. In 2010 I was awarded the Royal Society's Rosalind Franklin prize, and in 2012 the Institute of Physics Bragg Medal. In 2017 I was a Distinguished Visitor at the Australian Astronomical Observatory. I was appointed Gresham Professor of Astronomy in 2019.
I have written a book, together with Professor Stephen Blundell, called "Concepts in Thermal Physics'’, the second edition of which was published by Oxford University Press in 2009. This covers kinetic theory, thermodynamics, statistical mechanics and applications in astrophysics, atmospheric physics, information theory and many other topics.
In the Oxford University Press’s Very Short Introduction series, I have written a book on Black Holes.
My research interests include the physics of active galaxies, such as quasars; the formation of these objects at early times and their lifecycles. I am interested in the distributions of these objects throughout cosmic time and space. I am also studying objects in our own galaxy which produce jets of plasma that emit radio waves and move almost as fast as the speed of light, termed microquasars or nanoquasars. In many ways these objects resemble distant quasars, albeit evolving on much faster timescales. I initiated a project to obtain detailed spectroscopic measurements of the microquasars and related galactic objects. This is a new venture in time–domain astrophysics and is greatly enhancing our understanding of the physics behind these phenomena. This project is called Global Jet Watch, and comprises five telescopes separated in longitude around the planet so that at any time at least one of them is in night-time.
My research work on extreme sources of energy in the Universe gives a certain perspective on the challenge of the energy problem to be solved on Earth. My chemistry colleague Professor Fraser Armstrong and I organised a one-day forum to celebrate the 450th anniversary of St John's College entitled "Energy... beyond Oil”, which resulted in a book of the same title published with Oxford University Press. In 2006, we co-organized a Discussion Meeting at the Royal Society on "Energy... for the Future”.