Petra's world is ending. Earth has been destroyed, and only a few hundred scientists and their children have been chosen to journey to a new planet. They are the ones who must carry on the human race. Years later, Petra wakes to this new planet - and the discovery that she is the only person who remembers Earth. Petra alone now carries any hope for our future. Can she make them live again? 12+ Winner of the Newbery Medal.