The Firmament and the Puzzles of Creation.

Polina's plans to enjoy outdoor activities are ruined by unexpected rain. Distraught, she asks her mother why it rains at inconvenient times. Her mother's attempt to cheer her up is unsuccessful, so she suggests Polina should talk to her grandfather. He tells her about a time when there was no rain on Earth, according to the Bible. Polina, intrigued by the idea, listens as her grandfather explains the creation of the firmament on the second day, as per Biblical accounts.