In 1956 the philosopher Hannah Arendt delivered a series of lectures at the University of Chicago in which she considered the human condition from the vantage point of what were then "our newest experiences and our most recent fears". Three great events, she said, had shaped the modern age and determined its character: first, the discovery of America and the ensuing exploration of the world; second, the Reformation and the social and economic transformations that followed ; third, the invention of the telescope and the revolutionary perspective on the earth and the heavens promoted by astronomy. Before, however, these lectures could be published another great event occurred: on October 4, 1957 the first Sputnik was launched, inaugurating the space age.