January 28, 1986: Soon after launch, the Challenger shuttle falls out of the sky and into the sea. At the same time, Oliver Ines is born. He spends his childhood in an English village where his bedroom is covered in glow-in-the-dark wallpaper bearing the planets and stars. Decades later, he has become one of the most renowned astronauts of his time. When an enterprising billionaire taps him to lead a landmark mission to the distant moon Europa, Ollie makes a choice that will send his whole world spinning. As the mission advances deeper into uncharted territory, Ollie finds himself retreating into the past: his university days in London and years in the navy, relationships found and lost, becoming a husband and father. But will the world he remembers still be waiting for him 10 years later when he returns?