Written in Rock

A small rock found in the African desert has just handed scientists an extraordinary window into one of the most violent and consequential periods in the history of the Solar System. Inside this lunar meteorite, a chunk of the Moon knocked to Earth by an ancient collision, researchers have found evidence of a massive impact event 3.5 billion years ago, one that matches the timing of known impacts on Earth and in the asteroid belt. Three worlds but one shared bombardment and a story that may have