One clear day, Abigail thinks of a question and knows that she won't be able to do anything else if she doesn't have an answer to it. 'Daddy,' she asked, 'where did the Moon come from?' 'From the Earth, Abigail,' replied Daddy. 'The Moon was once a part of the Earth.' 'It was?' Abigail asked. 'But how did it get in the sky? And how does it stay in the sky? And why do we only ever see one side of the Moon?
