An asteroid that is twice the size of Big Ben could smash into Earth in just five years, NASA has warned. The asteroid, dubbed 2018 LF16, is predicted to potentially impact our planet on August 8, 2023. Thankfully, the chances of this are very low, with NASA predicted a 99.9999967 per cent chance of a miss. Asteroid 2018 LF16 is around 700ft (213 metres) wide - roughly twice the size of Big Ben's clock tower in London, or the same size as San Francisco's Golden Gate Bridge. The British daily cites NASA sources as claiming that the space rock could have a staggering 62 different potential impact trajectories with Earth with each of them potentially able to set the asteroid on a collision course with us over the next 100 years. While the chances of the asteroid crashing into Earth are low, if it does, it could cause widespread destruction. An object this big would have an impact force of 50 Megatons - the equivalent of the Tsar Bomba nuclear device. "That is more than 1,500 times that of