Project Hail Mary

In Project Hail Mary, astronaut Ryland Grace, suffering from amnesia, awakens on a spaceship millions of miles from Earth, alone with two dead crewmates. He gradually realizes he's on a desperate, one-way mission to save humanity from a global extinction event caused by a solar-dimming microbe called Astrophage. He must piece together his memories, understand his mission, and find a solution to save Earth, all while facing the daunting reality of being the sole survivor. The story also features flashbacks to the events leading up to the mission, including the discovery of Astrophage and the desperate measures taken to combat it.