An everyday science fiction adventure that starts with a girl who appeared from a distant star! !!
Satetsu works as an engineer at a spaceship shipyard while trying to find out the truth behind the death of his father who died during a planetary exploration 15 years ago. He spends his days as a family with Maki and her sisters, who he met when he was junior high school student, though he still continues the experiments in attempt to reproduce his father's accident.
One day, a work boat that is thought to be the debris of his father's spacecraft is brought in. Inside the ship is a lost alien named Sora. Satetsu then makes to decision to send her to the star where his father sleeps...! ?