In the year 2356, a devastating supernova has ravaged the planet, killing 99% of the world's population and rendering the Earth uninhabitable. Nineteen years later, humanity has rebuilt and begun to explore space, establishing massive space stations called "foundations" throughout the Solar System to monitor and maintain the fragile balance of the cosmos. Among these foundations is Stellvia, a state-of-the-art Earth-based space station that serves as a hub for intergalactic research and defense. Shima Katase, a determined and ambitious young woman, has just passed the entrance exams at the prestigious Space Academy and is about to embark on her journey to Stellvia as a cadet. Her dreams of exploring the galaxy and protecting the Earth from future cosmic catastrophes have driven her to this moment. As she boards the space station, Shima is about to discover that she is part of a select group of cadets chosen to pilot the most advanced spacecraft in the galaxy, the Selene, on a perilous mission to prevent a potentially devastating supernova from threatening the very existence of humanity.