Probably the most detailed description of a trip to Mars can be found in Kim Stanley Robinson’s Red Mars. Though it’s a science fiction novel, that work lays out an entirely plausible series of steps to found humanity’s first colony on an alien world, more in-depth than anything the public had seen before or, arguably, since. That’s a problem because as NASA begins to seriously discuss the prospect of putting astronauts on Mars, the public needs to be convinced that doing so is possible and, hopefully, even have a basic understanding of how such a mission might unfold.
Recently, we’ve seen a flurry of interest in solving this problem, not just proposing models for Mars landings, but explaining those proposals to the public. Elon Musk and Space-X have made a few stabs at it, but probably the most comprehensive came this week out of the BBC and Imperial College London.
As part of their upcoming documentary How To Put a Human on Mars, they asked Imperial College scientists to design a mission to do just that. The BBC has a wonderful interactive website up about it.
In essence, the mission is much like the lunar landings. The landing craft would take advantage of the Martian atmosphere with parachutes, but otherwise function much like a lunar lander. The biggest differences with this plan would be the trip there, which posits a two-part craft that can separate via an extendable tether. Once at its full length, the ship would spin to create gravity thanks to centripedal force (NOT centrifugal force!).
Though this has generally been seen as too difficult from an engineering perspective, the tether model might well be more effective — who knows? It seems like such wide-based tumbling would make it difficult to maintain a precise trajectory, but perhaps not. With regard to radiation, the researchers themselves admit that they’re resorting to shielding and a liberal helping of the “fingers crossed” approach.
Perhaps the most controversial element is that the astronauts would return home. After anywhere between three months and two years on the surface, astronauts would make their way toward a return vehicle landed near a pole long before their arrival. This makes sense, since carrying the return fuel on the initial trip would be prohibitively expensive. The return pod would land near a pole because they foresee a methane-powered solution, and hope to mine methane through the electrolysis of water to hydrogen and oxygen.
Other thinkers have recently tried to prepare the public for the idea that a first trip to Mars might well be one-way, and that any astronaut sent on such a mission would be certain to die on the surface — either of complications or old age.