At the edge of the world, on top of the world, is a window from our world into the rest of the universe: the telescopes of the European Southern Observatory (ESO) in Chile. Nearby are other observatories at Cerro Tololo, Las Campanas and the Atacama Large Milli­meter Array (Alma) at Chajnantor. These telescopes have shown how the expansion of our universe is accelerating; they’ve explored hundreds of planets around other stars; they’ve traced the motions of stars orbiting a super-massive black hole at the centre of our Milky Way galaxy. I am visiting with a half-dozen patrons who support such telescopes. Along with our host, Dr Fernando Comerón, our group includes a businessman who sits on the boards of universities; a retired schoolteacher; a Nasa engineer …