"I'd like to widen people's awareness of the tremendous timespan lying ahead -- for our planet, and for life itself. Most educated people are aware that we're the outcome of nearly 4bn years of Darwinian selection, but many tend to think that humans are somehow the culmination. Our sun, however, is less than halfway through its lifespan. Six billion years from now, it will not be humans who watch the sun's demise. Any creatures that then exist will be as different from us as we are from bacteria or amoebae."
Martin Rees, cosmologist and astrophysicist (b. 1942)