China and the US unveil "historic" new pledges on greenhouse gas emissions, as the two leaders meet for talks in Beijing.

Physicists send a beam of twisted light 3km through the air above Vienna, transmitting information in this way for the very first time in the open air.

Ministers have "completely oversold" the potential of shale gas, researchers from the UK Energy Research Centre tell the BBC.

European robot probe Philae has made the first, historic landing on a comet, scientists say, after descending from its mothership.

The pilot who survived the Virgin Galactic spaceship crash was thrown clear as the craft broke up around him, investigators say.