The lives of space shuttle astronauts were put at risk by a computer hacker who overloaded Nasa's communication system in 1997.

As the Nasa shuttle orbiting the Earth docked with the Russian Mir space station, a hacker interfered with the computer systems that monitor the heartbeat, pulse and medical conditions of the crewBritish-born astronaut Dr Michael Foale - who was on the affected mission but not told about the emergency - told the BBC's Panorama programme he was intrigued by its revelations. In the past year alone, the space agency has experienced more than 500,000 cyber attacks. There are fears in Washington's corridors of power that America's much-vaunted technological superiority has made it a target for its enemies. Roberta Gross, inspector general at Nasa, told Panorama: "We had an activity at a Nasa centre where a hacker was overloading our systems...to such an extent that it interfered with communications between the Nasa centre, some medical communications and the astronaut aboard the shuttle." However, after the programme was broadcast, Nasa denied that astronauts' lives has been put at risk. Panorama's investigation focuses on how internet and computer systems have become the vulnerable spots in the defences of Western nations.