Perhaps the best motivation for going to Mars is political. It is obvious that no single nation currently has either the will or the resources to do it alone, but a consortium of nations and space agencies could achieve it within 20 years.

In spite of the fact that religion looks backward to revealed truth while science looks forward to new vistas and discoveries, both activities produce a sense of awe and a curious mixture of humility and arrogance in their practitioners. All great scientists are inspired by the subtlety and beauty of the natural world that they are seeking to understand. Each new subatomic particle, every unexpected object, produces delight and wonderment. In constructing their theories, physicists are frequently guided by arcane concepts of elegance in the belief that the universe is intrinsically beautiful.

If you get a drill and drill down 5km beneath the ground, it's teeming with life - millions of tiny living fossils. They resemble the earliest life forms and suggest that life started under the Ground. The bible talks of Eden as a sunny parkland with white fluffy clouds, but it probably ascended from the region that we now associate with Hell.

Astronauts have been stuck in low-Earth orbit, boldly going nowhere. American attempts to kick-start a new phase of lunar exploration have stalled amid the realisation that NASA's budget is too small for the job.

Through my scientific work I have come to believe more and more strongly that the physical universe is put together with an ingenuity so astonishing that I cannot accept it as a brute fact....I cannot believe that our existence in this universe is a mere quirk of fate, an accident of history, an incidental blip in the great cosmic drama.

Science is about explaining the world, and religion is about interpreting it. There shouldn't be any conflict.

The development of artificial intelligence may well imply that man will relinquish his intellectual supremacy in favor of thinking machines. With oceans of time available for future innovation, there seems to be no reason why machines cannot achieve and surpass anything of which the human brain is capable.