Global warming? G8? Live 8? All of these pale into insignificance compared with what the guys at NASA have done. Fast on the great success of the Mars Rovers, we have the collision of a washing-machine-sized spacecraft and a comet the size of Manhattan. http://www.suntimes.com/output/news/cst-nws-comet05.html and great pictures on the BBC webstite. http://news.bbc.co.uk/1/shared/spl/...t0_a_mission_to_crash_into_a_comet/html/1.stm This is an astonishing achievement. What it proves is that we can, if need be, launch a thermonuclear device, intercept an asteroid or comet that is going to make an impact on the earth, and destroy it or alter its course. Because it isn't global warming, or globalisation, or genetic enginneering that will lead to mass extinction. It's having an asteroid the size of this comet smack right into the planet. The odds are long that it will happen anytime soon......but if it did happen, we're all dead, and really fast. But now, we have a chance of stopping it.