In a future world where Earth's resources are depleted, environmental pollution is severe, and human survival is in crisis, the world urgently needs to train young astronauts to explore outer space and bring back new energy sources to save the planet. Youths from around the world gather together, undergoing space training—including space knowledge, physical fitness tests, and zero-gravity tests—to become true astronauts. In the end, who will become the real astronauts? Let us wait and see...