This edition comes from the heart of one of the most influential – and surprising – organisations in the history of astronomy. Maggie and Chris have been granted rare access to the Vatican and its little-known observatory, the Specola Vaticana, perched on a hilltop 30km outside Rome. — There they explore its rich history and contemporary cutting-edge science, going inside the Vatican walls to visit the Tower of the Winds, a secret antique sundial that revolutionised the length of the year; the remains of a nest of telescopes atop an old medieval church where the science of spectroscopy was born; and the modern labs, manned by priest scientists who study a range of contemporary astronomical problems, from meteorites to binary stars to the birth of the universe itself.