Farmer in the sky is a 1950 science fiction novel by american writer robert a heinlein about a teenaged boy who emigrates with his family to jupiter s moon ganymede which is in the process of being terraformed. Farmer in the sky is definitely in the juvenile category the hero is william lermer a young man who emigrates to ganymede one of jupiters moons its being terraformed as new colonial land for a crowded earth he travels there with his father his fathers new wife and his step sister the fathers remarriage and decision to emigrate is handled very deftly showing the tumult of feelings . The unbridled optimism and can do attitude of farmer in the sky makes me smile even though the main characters are fleeing an overcrowded earth the sense of possibility that heinlein had about humanitys future was a wonderful thing. Farmer in the sky is a 1950 science fiction novel by robert a heinlein about a teenaged boy who emigrates with his family to jupiter s moon ganymede which is in the process of being terraformed