If you want a formal description, I’m a Professor of Geophysics. This means that I have the good fortune to be employed by a University to undertake research and teaching about how our planet works. I’ve now spent 29 years in the department of Earth Sciences at Royal Holloway (part of the University of London) where I became head of department (2008-2012) and where I am now director of our distance-learning MSc in petroleum geoscience. But perhaps I should say a bit more about what drives me.
I’ve had three scientific loves in my life. I began with astronomy, as did many who were young at the time of the Apollo missions. Then, entirely by accident, I stumbled into geology and discovered a wonderfully multi-disciplinary field that drew upon many other sciences such as physics, chemistry and biology. However, after fifteen rewarding years studying our world, I became obsessed by the question “Is the Earth Special?” and that has led me into my third love – astrobiology, the science of life beyond Earth. Astrobiology is even more multi-disciplinary than geology since it uses the same fundamental sciences but also draws upon additional subjects such as engineering (how do we build instruments to detect life?), geology itself (what do the rocks of Mars tell us about its history?) and psychology (how would we communicate with a truly alien mind?).
Despite this gradually changing focus, the application of physics to solving problems has been a constant thread through my work. I would define physics broadly to cover any attempt to mathematically approximate reality. For me, a computer simulation of coral-reef build-up over a few thousand years is just as much “physics” as Einstein’s famously mathematical models of space and time. The beauty of quantitative descriptions of nature is that they allow you to test ideas in a rigorous way and they often lead to deeper insights than purely qualitative approaches. However, as George Box first said, “All models are wrong but some models are useful” so don’t be fooled into thinking an idea must be right just because it has been expressed mathematically. Indeed, my colleagues often take me into the field to “touch the rocks” just to remind me that the real world is infinitely more interesting, varied and complex than anything yet captured by anyone’s equations. That’s my hand above, touching Snowball-Earth deposits in Shetland.
So, where has my journey through astronomy, geology and astrobiology taken me? Well it’s allowed me to write lots of scientific papers and to build computer models of everything from single sand grains up to entire planetary systems. The sand was in turbidity currents, massive undersea avalanches of sand and mud which flow for hundreds of kilometres across the deep-ocean floor. These sand-grains were the fundamental components of computer models I’ve built for oil-industry use in collaboration with Midland Valley Exploration (www.mve.com). The picture above shows an undersea channel in the Mediterranean Sea simulated by one of my models. Over the years I have written computer programs simulating geological processes from the formation of coral atolls through to the propagation of sound-waves in the complex subsurface of our planet.
In astrobiology my main concern has been with the Moon’s influence on Earth’s life-friendliness. Is a large Moon necessary for a highly habitable planet? My key discovery, based upon mathematical modelling of how the Moon has receded from the Earth since they both formed four and a half billion years ago, is that our large Moon does NOT stabilize the Earth’s axis. In fact it very nearly destabilizes it; a conclusion which flatly contradicts all received wisdom on the subject. At the very largest scale, I have looked at how the slowly wobbling orbits of planets in our solar system have affected the frequency of ice-ages and how this could be very different in planetary systems orbiting other stars.
I live in Marlborough along with my wife, three children and two dogs but I still find time for the three Rs; reading, writing and running.