"Rocketman" lays out the moon/mars proposal, Derek. I think he is way under on cost. But even with his numbers, it doesn't figure out.
Putting The Cart Before The Horse
It has been widely reported that President Bush will announce a new space policy initiative later this week that will include sending humans back to the moon and eventually on to Mars.
The visionary new space plan would be the most ambitious project entrusted to the National Aeronautics and Space Administration since the Apollo moon landings of three decades ago. It commits the United States to an aggressive and far-reaching mission that holds interplanetary space as the human race's new frontier.
Regular readers of my blog know that I am a strong advocate for manned Mars missions, but that I am also deeply suspicious of NASA’s ability to effectively administer a large scale program of this type. This is no longer the 1960’s, the cold war is long over, and a large portion of American public will not tolerate the level of spending it took to accomplish the Apollo program, especially if, as with most modern-day NASA programs, it ends up being significantly over budget and behind schedule.
Of course nobody has heard the actual proposal yet, and I am waiting to hear exactly what will be proposed before I pass final judgment on it. But in my opinion there is one item that absolutely must be included as part of the proposal, and that is a new launch vehicle that will drastically reduce the cost of space access.
The most conservative scheme for the amount of mass that must be launched into low Earth orbit for a manned Mars mission is probably the Mars Direct plan. Mars direct assumes that all the fuel required for the return trip will be manufactured on Mars, but even with this weight savings the plan still requires launching 200,000 lbs into LEO. With current launch costs being around $8,000/lb, just the launch costs for this plan would add up to $1.6 billion.
Mars direct also assumes that it would only take two launches to accomplish the mission, but the problem is that no current launcher has the capability to launch that much mass at one time. The Saturn V had that capability, but they are of course no longer being produced. Recreating the Saturn V would be no easy feat, but it could be done. However, recreating a vehicle designed and built over 35 years ago is not a step forward, it is a step backward.
If the Bush proposal ends up being similar to what has been reported, it will require even more mass to be launched. For one, NASA is unlikely to undertake a mission as ambitious as Mars direct, but also because sending humans back to the moon as part of the plan will require even more launches. I don’t know how much total mass will need to be launched to fully realize the goals Bush will propose, but it will be significant.
But what if we could reduce launch costs down to $1,000/lb?
Let’s assume that by the time humans land on Mars, a total of 400,000 lbs has been launched into LEO. At current rates, launching this much mass would cost around $3.2 billion. But at $1,000/lb the cost would only be $0.4 billion, for a savings of around $2.8 billion.
And that is where the title of this post comes in. We shouldn’t put the cart before the horse and undertake missions using existing high cost expendable launch vehicles. Instead we should spend some money up front to significantly reduce launch costs. $2.8 billion is an enormous amount of money, and if we can design and build a fully reusable space transport that can reduce launch costs to $1,000/lb for that price, the overall cost of the mission would be exactly the same as if we used existing launchers.
None of the three main components used in the Apollo program (the Saturn V, the command module and the lunar lander) saw any significant use after the program ended, and it would be a tremendous waste to end up in the same situation after spending the kind of money it will take to land humans on the surface of Mars. Hopefully, the ultimate legacy of Bush’s proposal will be to truly open the solar system by dramatically reducing the cost of space access.
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