NASA has revealed which countries could be hit if a "city killer" asteroid strikes Earth with a map of the risk corridor. Scientists have slashed the odds of a collision between asteroid 2024 YRA and our planet to a one-in-43 chance – or just over two per cent. 7 The asteroid could strike Earth at Christmas time, 2032 Credit: Getty 7 Asteroid 2024 YR4 as observed by the Magdalena Ridge 2.4m telescope at the New Mexico Institute of Technology on January 27, 2025 Credit: AFP 7 The giant boulder rocketed to the top of Nasa's impact risk list when it…