Chinese satellite sends 'hack-proof' message

China has successfully sent "hack-proof" messages from a satellite to Earth for the first time. The Micius satellite beamed messages to two mountain-top receiving stations 645 km (400 miles) and 1,200 km away. The message was protected by exploiting quantum physics, which says any attempt to eavesdrop on it would make detectable changes. Using satellites avoids some limitations that ground-based systems introduce into quantum communication. More

(Source: BBC News - Aug 13)