Staving Off Starvation on Ganymede: Farmer in the Sky by Robert A. Heinlein

In this bi-weekly series reviewing classic science fiction and fantasy books, Alan Brown looks at the front lines and frontiers of the field; books about soldiers and spacers, scientists and engineers, explorers and adventurers. Stories full of what Shakespeare used to refer to as “alarums and excursions”: battles, chases, clashes, and the stuff of excitement.

Robert Heinlein never shied away from putting the protagonists of his juvenile novels into nasty situations, and Farmer in the Sky is no exception. The solar system is on the verge of a Malthusian disaster, with the human population rapidly outstripping food supplies. Though surrounded by material riches previous generations would no doubt envy, people are counting every calorie and living on the edge of hunger. Even the staggering cost of transforming hostile worlds into farmland is not too steep if it will help stave off the inevitable. Young Bill Lerner volunteers to become a pioneer farmer on the Jovian moon of Ganymede, and to grow into adulthood on the far-off frontier.

This is one of the Heinlein juveniles I didn’t get around to reading when I was young. I suspect it was because I thought going to work on a farm seemed like a terrible waste of a journey through space. But toward the end of my career, I was working an hour away from home, and Farmer in the Sky was one of the books I picked up in audio version to help pass the commute. The discs were from Brilliance Audio, and the reader, Nick Podehl, did an excellent job. It even had nice cover art, which (while it was not credited) looked like the work of Bob Eggleton. It is difficult to write a review from an audiobook, though, so I borrowed a print copy from my son (being in a multigenerational family of science fiction geeks can come in handy). His copy was a 1988 paperback reprint from Ballantine Books, marred by a perfunctory cover illustration and cover copy that seemed like a first draft mockup.

I probably would have read the book sooner if I had known the protagonist was a Boy Scout, as I am also part of a multi-generational Scouting family. An abridged version of Farmer in the Sky originally appeared in Boy’s Life magazine in 1950 as “Satellite Scout,” and Bill’s experience as a Boy Scout is a major element of the plot. Like Bill in the book, I’ve found that the skills and values I’d learned in the Boy Scouts to be useful in adulthood. To address the elephant in the room, however, I am absolutely appalled at how the leadership of the Boy Scouts betrayed the values they were teaching as they hid evidence of sexual abuse over the years. While I would be happy to discuss the role of Scouting in Heinlein’s fiction in the comments after this review, I would ask we not turn it into a discussion of behavior we all agree is reprehensible.

Over the years, Boy’s Life featured quite a bit of what is now called YA fiction, and a fair amount of that was science fiction (as summarized in this article in the Encyclopedia of Science Fiction). This included other works from Robert Heinlein, including two short stories: “Nothing Ever Happens on the Moon,” and “Tenderfoot in Space.” An abridged version of The Rolling Stones appeared as “Tramp Space Ship,” and there was even a comic strip adaptation of Between Planets.


About the Author

Robert A. Heinlein (1907-1988) was one of America’s best known science fiction authors, frequently referred to as the Dean of Science Fiction. I have regularly discussed his work in this column, including Starship Troopers, The Moon is a Harsh Mistress, “Destination Moon” (contained in the collection Three Times Infinity), The Pursuit of the Pankera/The Number of the Beast, and Glory Road. From 1947 to 1958, he also wrote a series of a dozen juvenile novels for Charles Scribner’s Sons, a firm interested in publishing science fiction novels targeted at young boys. These novels include a wide variety of tales, and contain some of Heinlein’s best work (the books I’ve already reviewed in this column are underlined, and have links to the review): Rocket Ship Galileo, Space Cadet, Red Planet, Farmer in the Sky, Between Planets, The Rolling Stones, Starman Jones, The Star Beast, Tunnel in the Sky, Time for the Stars, Citizen of the Galaxy, and Have Spacesuit Will Travel. This is not the first time Farmer in the Sky has been reviewed on, as the inimitable Jo Walton looked at it over a decade ago.


Starvation and Terraforming

The pioneering English economist Thomas Robert Malthus (1766-1834) posited a theory that human populations would inevitably grow past available food supplies, and catastrophe would result, with wars, famine, and disease bringing the populations back down. His views were both controversial and highly influential, and are still debated in the modern era.

The idea of a Malthusian collapse runs through many of Robert Heinlein’s works, but never so directly as in Farmer in the Sky. Heinlein’s solution to the trap Malthus predicted was rooted in the American experience of the eighteenth through early twentieth centuries and the idea of avoiding collapse by expanding into new frontiers. His works envision humanity moving throughout the solar system and taking action to make its worlds more habitable, from building atmosphere plants on Mars to the audacious project of transforming the moons of the outer planets into habitable worlds.

Heinlein put a lot of thought into what would make Ganymede a viable option for human life. Heating the world to Earth-normal conditions would require a lot of heat, using “mass energy converters” that put our current atomic power plants to shame. He estimated it would take fifty years to break enough of the surface ice down into hydrogen and oxygen to produce an atmosphere that, while thinner than Earth’s, would have a partial pressure of oxygen sufficient for breathing. And the atmosphere would be kept cloudy by a ‘heat trap’ to maximize the greenhouse effect. The moon’s rock would be broken down into sterile soil that could be seeded with earth microbes and turned into arable land.

Heinlein’s vision was unfortunately more than a bit overoptimistic, given what we have learned about the outer planets and their moons thanks to the robotic probes employed in the latter half of the 20th century. One of the biggest problems is radiation. While Ganymede is one of the rare moons with a magnetosphere, it is not up to the challenge of protecting its surface from the radiation and energetic particles generated by Jupiter. Early settlers would have to live underground. Moreover, there is a lot more water on Ganymede than Heinlein imagined—enough that heating the planet to Earth-normal temperatures would create a world covered by a deep ocean, with powerful tides and currents generated by Jupiter and its moons.

That might be an interesting setting for science fiction stories, but is far different than the world Heinlein described. In any event, without power plants that directly convert matter to energy, the power to heat a world to the extent needed will remain beyond human capabilities. And I suspect that any project of this scale, because major endeavors always end up being more difficult than they look in theory, would not be the work of mere decades (as they are in Heinlein’s stories) but of centuries. I freely admit, however, that I am not an astronomer, engineer, or scientist, and would welcome the input of anyone who understands such subjects better than I do.


Farmer in the Sky

Bill Lerner is an angry young man, perhaps the angriest protagonist of any in Heinlein’s juveniles. His mother, Anne, recently died, and he is not coping well. It doesn’t help that his dad, George, is one of those absentminded people who, while good at his work and career, struggles to cope with the challenges of day-to-day life. Thus, Bill has stepped into the caregiver role. They live a comfortable life, although hunger is always an issue on the overcrowded Earth of the future.

Then, out of the blue, George announces he wants to emigrate to Ganymede…and leave Bill behind. Bill convinces his father that they should go together, and Heinlein takes some time describing the process used to screen potential candidates for emigration. Next, Bill’s dad reveals he is marrying Molly, a widow who works in his office. Molly has a daughter, Peggy, so Bill is now stuck with a kid sister he didn’t want. Bill feels that his dad has betrayed his mother’s memory, skips the wedding, and doesn’t see his father and new family until launch day.

Bill decides at the last minute to bring his Scout uniform shirt, and since his luggage is at the weight limit, puts it on under his other clothes. Since he hasn’t been eating well lately, he still manages to squeak in just under the weight limit. He flies to orbit in a shuttle named Bifrost, and meets an entitled kid named Hank Jones, who fast-talks their way into the ship’s control center. They meet the captain, who jokes about his career being derailed when pirates kidnapped him—Bill later finds out from his father that the story was true. Along the way, Heinlein fills the reader in on the details of spaceflight.

They then transfer to Mayflower, the atomic rocket that will take them to Ganymede; because of the radioactivity of the ship’s power plant, she will never actually land on a planet. While Heinlein doesn’t dwell on it, we see that Bill begins to heal the relationship with his father and new family. He also befriends the Chief Engineer, Mr. Ortega, who spends a lot of time explaining to Bill (and also the reader) the operations of an atomic passenger ship. Bill also gets the idea of starting up Scout troops on the ship, an idea popular with adults, as there is far too much time on everyone’s hands during their months-long journey (his stepsister Peggy joins a Girl Scout troop). Bill becomes a hero when a meteorite punches a hole in his dormitory room, and he ingeniously stuffs his Boy Scout shirt to plug the breach.

The colonists transfer to the colony’s single orbital shuttle, Jitterbug (and I was shocked by the lack of redundancy that represented). When they finally disembark, they find living conditions abysmal, as the colony is overwhelmed by the number of colonists. Instead of being offered finished farms, they are offered plots of unimproved rock, and in order to eat until they can get their own farms going, they must hire themselves out as sharecroppers to established farmers. Bill finds there are Boy Scouts on Ganymede, but to his chagrin, they insist that newly arrived Scouts must start over to re-earn all their ranks and badges. As an engineer, Bill’s dad is offered an office job in town. Peggy turns out to be unable to adapt to the thin atmosphere, and must live in a special pressurized room, tying Molly to her constant care. So Bill sets out to start their farm on his own.

Here Heinlein gets to expound at great length about how Ganymede has been reshaped into a habitable environment, and how raw rock is turned into farms. Fortunately, their farm is near the established farm of the Schultz family, who prove to be the best possible neighbors, helping Bill get the land processed and giving him advice and assistance. Poppa Schultz has an apple tree he planted upon arrival, and is considered eccentric because he hands out apples like they are valuable treasures (which in the long run, they truly are). Theirs is a large family, with lots of kids, and one of them is a daughter named Gretchen. This being a Heinlein juvenile, the fact that Bill is attracted to her is never discussed in any detail, but he does tease her about her red hair, and when considering returning to Earth later in the book to continue his education, muses that no Earth girls could ever measure up to Gretchen. These clues are enough for readers to imagine that Bill may end up marrying Gretchen sometime in the future.

Their soil eventually gets processed, and Bill builds a stone house the family can move into (with Peggy still needing a pressurized room). And then disaster strikes the colony. There is a rare alignment of Jupiter’s moons (as it turns out, an impossible alignment, a somewhat rare scientific mistake on Heinlein’s part), and the tidal forces create a gigantic earthquake. This takes the power plant that runs the heat trap offline, and the temperatures begin to plunge to Ganymede’s normal temperatures, far below zero (the fact there is only a single heat trap keeping the moon habitable strikes me as a criminally negligent lack of redundancy). Bill and his family make it back into town where there are still a few heated buildings, but their house is destroyed by the earthquake and their crops frozen. Peggy, already frail, dies during their journey to town. The Schultz family survives on their farm by chopping down Poppa’s precious apple tree and burning it in their fireplace to keep warm.

After the heat trap is brought back online and normal conditions restored, Bill and his father get the farm back on track, and then Bill volunteers to work on a survey team looking at unexplored parts of the moon. There are some discussions of the coming Malthusian disaster with the team leader, where Heinlein lays out his ideas on the subject in explicit detail. But then, saving the narrative from this depressing turn, Bill and a friend (Hank Jones, who he met way back on Bifrost) discover a cache of devices left by an alien civilization, which causes quite a stir.

The book ends as George tries to convince Bill to return home to Earth to continue his education, but Bill realizes he doesn’t need to attend a school to learn, and decides he is already home.


Final Thoughts

Farmer in the Sky ends up being one of the better of Heinlein’s juveniles. Bill’s growth from an angry and selfish teenager into a mature adult is realistic and satisfying. The description of the various stages of the trip to Ganymede, and the details of its terraforming, might be dull in other hands, but Heinlein does a great job bringing the expository details to life. There are some aspects of the story that stretch credulity, but it’s always interesting, and in the end, quite emotionally satisfying.

Now, I turn the floor over to you. If you’ve read Farmer in the Sky, I’d enjoy hearing your thoughts. And also any thoughts you might have on atomic rockets, terraforming, or any of the other topics raised in the story.

Alan Brown has been a science fiction fan for over five decades, especially fiction that deals with science, military matters, exploration and adventure.


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