Written in the stars: 7 celestial events that may have changed history

If you were paying close attention to the skies last night, you may have observed what is known among stargazers as a 'pink supermoon'. Here, Guy de la Bédoyère describes seven celestial events that may have changed the course of history, from the comet that carried William the Conqueror to victory in 1066 to the eclipse that helped Lawrence of Arabia defeat the Ottomans...