Devastation could arise insidiously, rather than suddenly, through unsustainable pressure on energy supplies, food, water and other natural resources. Indeed, these pressures are the prime 'threats without enemies' that confront us.

I'm not myself religious but have no wish to insult or denigrate those who are.

To most people in the UK, indeed throughout Western Europe, space exploration is primarily perceived as 'what NASA does'. This perception is - in many respects - a valid one. Superpower rivalry during the Cold War ramped up US and Soviet space efforts to a scale that Western Europe had no motive to match.

I suspect there could be life and intelligence out there in forms that we can't conceive. And there could, of course, be forms of intelligence beyond human capacity-beyond as much as we are beyond a chimpanzee.

The carbon dioxide concentration in the atmosphere is measured. It's uncontroversial. It's going up. We know that has a tendency to warm the atmosphere and we should be worried about that.

There may be organic life out there, or maybe machines created by long-dead civilizations, but any signals, even if they are difficult to decode, would tell us that the concepts of logic and physics are not limited to the hardware in human skulls, and will transform our view of the universe.

Indeed, our everyday world presents intellectual challenges just as daunting as those of the cosmos and the quantum, and that is where 99 per cent of scientists focus their efforts. Even the smallest insect, with its intricate structure, is far more complex than either an atom or a star.