In a pre-launch flashback, Eva Stratt visits Ryland Grace in a secured room at Baikonur. She justifies drugging and sending him by outlining the imminent global collapse Astrophage will cause: food shortages leading to wars, famine, societal breakdown, plagues, and mass death. She frames Hail Mary as humanity’s only hope, accepting any sacrifice to increase its chances.

In the present, eighteen days into his return trip, Grace crosses Tau Ceti’s heliopause. He battles loneliness, monitors rising radiation, and briefly shuts off spin to track Rocky’s ship by Petrovascope, knowing relativistic red-shift will soon end even that distant visual contact.

Grace inventories dwindling real food and samples the coma slurry, finding it nearly inedible. He considers seeding Venus with Taumoeba upon returning to the solar system and postpones further comas to watch navigation and avoid catastrophic course errors.

He prepares Earth-return “beetle” probes to carry Taumoeba mini-farms. After rejecting xenonite containers, he and Rocky had chosen a tough Eridian steel casing Earth can cut. Each sealed capsule contains a Venus-like atmosphere and a long Astrophage coil for years of microbial feeding. Grace mounts the farms externally, adds counterweights to preserve guidance tolerances, and refuels the beetles.

While refueling from his large Astrophage bin, Grace smells rot and realizes the odor is from dead Astrophage. He concludes Taumoeba have escaped into his supply, creating a new crisis that threatens his fuel and the mission home.