Interview with the author

Paul Murdin

What do we know about the birth of the Universe?

We can see the relic radiation of the Big Bang itself – the Cosmic Microwave Radiation – and we can handle some of what was made in the Big Bang before that time: material containing hydrogen (such as water). I’d say we are on firm ground talking about the first second of the Universe and afterwards. What happens in that time can be described in terms of well-established physics: gravity, atomic and nuclear physics, thermodynamics etc. Before the first millisecond or so, it becomes increasingly unclear because the relevant physics is particle physics, which is still being developed. Also, some sort of physics underlies the rapid expansion of the Universe: the details are almost unknown, except for generalities like the ‘cosmological constant’. And before inflation, who knows? There is more to do!

Which Solar System bodies most deserve to be explored?

Dried out Mars and smoggy Titan. Saturn’s satellite, Titan, is almost unexplored, but it has a bearing on the important question of how life originated. Mars may be Earth’s future, Titan is Earth’s past.

What are astronomy’s big challenges?

Astronomy has progressed in spurts sparked by new instrumentation, but these are larger and more expensive. The world can now afford a space telescope, a global radio astronomy array, a Mars sample return mission and a gravitational wave antenna, but soon it will have to choose only one new instrument at a time. How will it make that choice?

Paul Murdin is an astronomer and former president of the European Astronomical Society