In Project Hail Mary, amateur astronaut Ryland Grace must travel light years from Earth to save humanity from a dying Sun. The stakes are high, to say the least. But author Andy Weir was intentional about centering hope in his bestselling novel, which inspired the recent blockbuster film starring Ryan Gosling. In today’s episode, Andy Weir joins Here and Now’s Indira Lakshmanan to discuss his creative world-building process, and why he remains optimistic about our ability to collaborate in the face of existential threats. To listen to Book of the Day sponsor-free and support NPR's book coverage, sign up for Book of the Day+ at plus.npr.org/bookoftheday