It might sound like a terrifying scene from an apocalyptic science-fiction film. But the world's space agencies have now made a rare emergency decision as the chances of Earth being hit by a 'city-killer asteroid' rise. As the risk increases, an international team of astronomers has been granted use of the James Webb Space Telescope (JWST) to determine how much damage the asteroid would cause. The best estimates currently suggest the asteroid is up to 90m (300 ft) wide. That would make it around the same size as New York's Statue of Liberty or London's Big Ben. #asteroid #nasa #armageddon