Project Hail Mary with Andy Weir

In this episode of StarTalk Radio, host Neil deGrasse Tyson welcomes back author Andy Weir to discuss his latest bestseller, Project Hail Mary, and its upcoming film adaptation starring Ryan Gosling. Weir delves into the scientific intricacies of his fictional alien organism, Astrophage—a star-eating microbe that converts stellar energy into mass for propulsion—explaining how it threatens Earth's habitability by dimming the sun. The story follows Dr. Ryland Grace, a reluctant hero who is drugged and sent on a suicide mission aboard the interstellar spacecraft Hail Mary, powered by Astrophage. Along the way, he befriends Rocky, a five-limbed, rock-like alien from the planet 40 Eridani A, whose species evolved in extreme conditions: a thick ammonia atmosphere, high pressure, and total darkness, leading to a unique echolocation-based consciousness and no need for object permanence. Weir emphasizes the rigor behind his world-building, using real astrophysical constraints—even though the exoplanet he based Rocky's world on was later disproven. The conversation also touches on the challenges of adapting complex science into film, Weir’s advice for aspiring writers, and his pride in crafting aliens that feel truly alien, not just costumed actors. The episode ends with a celebration of Weir’s impact on sci-fi storytelling and a humorous nod to the film’s potential for viral moments, like CGI Rocky running up the Philadelphia Art Museum steps.