Checking "Ти – космос" for realism: what in the film is science, and what is for the sake of the plot

The story of a space trucker from Khmelnytskyi, who remains the only human in the universe, is poignant and piercing. But is it realistic? We discuss the main ideas of the film with a candidate of technical sciences: from dumping nuclear waste on Jupiter's moon to washing your hair on a spaceship.