Kerbal Space Program isn’t a new game, but as it has yet to relinquish its grip on my free time, I’ve been thinking a lot about why such a labor-intensive, story-free game can be so enthralling.
For the uninitiated, Kerbal is a game about the development of a space program for funny little green creatures called Kerbals. They live on Kerbin, the third planet around the star Kerbol, orbited by a grey, airless satellite called the Mün. The player designs and pilots ships to aid the Kerbals in their exploration of their solar system. The game offers a simple narrative by rewarding the player with money and access to new parts for various achievements, but it’s largely a sandbox game, where players set their own goals. Given the game’s high difficulty level and steep learning curve, Kerbals appear to have no concept of mortality, as they eagerly sign up for new missions despite the loss of dozens of their predecessors.
The game was developed as a side-project by Squad, a Mexican software company, and quickly acquired cult status, not only among nerdy amateurs like Randall Munroe of xkcd, but—somewhat alarmingly—among actual NASA engineers and astrophysicists.
What strikes me as so remarkable about Kerbal’s popularity is the fact that little about it really seems like a game. There’s no plot bringing the players from one mission to the next, the kerbalnauts have no dialogue or individuality, and the basic gameplay is solving physics problems. There are no weird aliens to discover, like in No Man’s Sky, and no galactic space battles as in E.V.E. Online. You just… go to space. There’s nothing to win, nothing to conquer, no rewards. It’s a game where the joys are almost entirely in the journey, not the destination. Why does it work?
The game is well-built. Available directly from Squad or via Steam, it’s a feat of physics simulation, as the player constructs rockets from a list of parts, each with certain functionality, as well as mass. You balance thrust and fuel against weight, account for aerodynamics, make room for a pilot, and blast off into space. In career mode, your parts list is limited by the science you can generate by hauling experiments into space, and your budget is based on prizes for accomplishing specific tasks. But it’s a light bit of organization in the larger sandbox game, where you are only limited by your creativity. Everything then proceeds in a physically accurate way, based on the decisions and maneuvering of the player and the craft (although you can always speed up time, to pass through the long journeys through empty space). It’s utterly simple. Why should it be fun?
My conclusion is that Kerbal Space Program is fun to the extent it’s a role-playing game at heart—even though there are no traditional RPG elements in the actual game play. Instead, it takes one step back, and rather than writing out a narrative for you, it gives you the opportunity to construct one in your own mind by giving just the right hints and by making your tasks just as difficult as they need to be.
It helps, of course, that the game’s space setting is already incredibly rich in our cultural history and imagination. The first tasks you can accomplish—getting to space at all, orbiting the planet, landing on the Mün/Moon—are the domain of the great heroes of the twentieth century. The player becomes Robert Goddard, gazing into the sky and imagining visiting the heavens. Or Yuri Gagarin, climbing aboard an unproven rocket and watching the planet spin below. Or even John F. Kennedy, choosing to go to the moon in this decade and do the other things, not because they are easy, but because they are hard. It’s got some romance to it.
And it works, in Kerbal, because Kennedy is right: sending kerbals to the Mün is not easy, and the game is worth playing because it is hard. Rocket science is actually as difficult as promised. Once the rocket is launched, there’s no turning back, no chance to refuel or add another battery pack. Reaching space, intercepting the Mün’s orbit, coming to a gentle stop on the surface, and bringing the crew home: each of these are careful, precise tasks, which can only be accomplished with the resources already on board. Doable, but never easy, never automatic, never trivial. Because of the challenge, there’s a rush when the first kerbal steps off the ladder, and achieves that one small step/one giant leap moment.
Or doesn’t. Without the PhDs on retainer or the staff at Cape Canaveral, the player’s success rate is going to fall well short of 100%. Rockets veer off course, landers reach the surface a little too quickly to survive, capsules overheat on re-entry—or the spaceship simply runs out of fuel and maroons its crew in orbit or on another world.
The game has few consequences for mission failure or the loss of an astronaut, but the story of spaceflight is deeply baked into our psyches by the likes of Interstellar, Apollo 13, or Gravity, or the real-life tragedies of Challenger or Columbia. Death in space hurts, even when it’s a little green astronaut with a funny name. Worse, somehow, is the possibility of surviving a space disaster, but with no means of returning home. Kerbal Space Program does not need any in-game mechanism to punish you for these failures; it’s impossible to avoid role-playing the tragedy.
Because of that, you get extra motivation to succeed and to do slightly more than just reload and retry. Lost astronauts also dare the player to take on more challenging rescue missions, and develop finer skills in order to make up for past failures, rather than arbitrarily advancing in difficulty on the designer’s timeline.
And that, ultimately, is what makes the game tick. After each mission, the next one arises organically. There’s always the next world to visit, or a lost astronaut to bring home, or a new rover design to explore further. The path is laid not by the designer’s plot ideas, but by our own history in space, and by the needs of a developing space program.
Plus, of course, without the constraints of terrestrial politics and money, you can always go further and fly higher.