Noted science writer Chet Raymo explores how we found our place in space and time, and what it has meant to humankind. In "Walking Zero," Chet Raymo uses the Prime Meridian--the line of zero longitude and the standard for all the world's maps and clocks--to tell the story of humandkind's intellectual journey from a cosmos not much larger than ourselves to the universe of the galaxies and geologic eons. As in his highly praised "The Path" and "Climbing Brandon, " Raymo connects personally with the story by walking England's Prime Meridian from Brighton through Greenwich to the North Sea. The Prime Meridian passes near a surprising number of landmarks that loom large in science: Isaac Newton's chambers at Trinity College, Cambridge; Charles Darwin's home at Down, in Kent; the site where the first dinosaur fossils were discovered; and John Harrison's clocks in a museum room of the Royal Observatory, among many others. Visiting them in turn, Raymo brings to life the human dramas of courageous individuals who bucked reigning orthodoxies to expand our horizons, including one brave rebel who paid the ultimate price for surmising the multitude of worlds we now take for granted. A splendid short history of astronomy and geology, "Walking Zero" illuminates the startling interplay of science, psychology, faith, and the arts in our understanding of space and time.