On two days in 1761 and 1769 hundreds of astronomers pointed their telescopes towards the skies to observe a rare astronomical event: the transit of Venus across the face of the sun.United by this momentous occasion, scientists from around the globe came together to answer the essential question: how can the universe be measured? In Chasing Venus Andrea Wulf paints a vivid portrait of the rivalries, triumphs and misfortunes that befell these men, along with their passion and determination to succeed. This extraordinary book tells their story and how one single event prompted the first international scientific collaboration.