America's space program is at a turning point. After decades of global primacy, NASA has ended the space-shuttle program, cutting off its access to space. No astronauts will be launched in an American craft, from American soil, until the 2020s, and NASA may soon find itself eclipsed by other countries' space programs.

With his signature wit and thought-provoking insights, Neil deGrasse Tyson--one of our foremost thinkers on all things space--illuminates the past, present, and future of space exploration and brilliantly reminds us why NASA matters now as much as ever. As Tyson...