The waterproofing burns off during the shuttle's fiery re-entry into Earth's atmosphere, leaving the tile-encrusted spacecraft vulnerable to the elements after landing.

CNN: Technicians finish toasting shuttle tiles

In a paper in this week's Nature, John Harries and his colleagues describe their analysis of the longwave infra-red radiation leaving the earth.

ECONOMIST: Climate change: Getting real | The

Science fiction inspired him though his first job after leaving school was in the down-to-earth British civil service, which gave him plenty of time to think and write.

ECONOMIST: Sir Arthur C. Clarke, visionary, died on March 18th, aged 90