John Strickland makes the case against it over at The Space Review today. I don’t think this is right, though:
It is hard to imagine being able to quickly set up such a [lunar] base without a launch campaign of at least five HLV launches per year. To do this you will also need one or more cryogenic propellant depots in Earth orbit to assure that the propellant to support such a launch rate from LEO to the Moon or Mars is guaranteed to be available in LEO before the buildup begins. (Without the depots, the total cargo delivered to a base site for a given number of SLS launches would be cut about in half). The depots would also need to be launched by HLV boosters. Assuming a minimum of five SLS launches per year at $5 billion a launch, the total cost is $25 billion a year, far beyond NASA’s overall annual budget, let alone its human spaceflight budget. With a launch every two years, it would take a decade to provide the most minimal equipment for a surface base, and most of that would have been sitting there for many years and would thus likely be thermally damaged and unusable.
I really need to see the work here. On what is he basing the need for five launches per year? And how does the depot double the lunar payload? And why does the depot or depots require a heavy lifter? Is he assuming they will be launched full? The depot structure itself doesn’t weigh all that much and could easily go up on an Atlas or even a Falcon 9. And doesn’t that five billion per launch for the SLS assume a low flight rate? Presumably, if they really could do five a year, the per-flight cost would be much less. I’m not saying his numbers are wrong, but I’d need a lot more explanation to accept them. I do agree with this:
In addition to the political impasse over booster development, the nature of the current NASA planning system results in a vicious circle, seemingly created by deliberately not including advanced technology components into future mission plans. The reasoning behind these decisions are that the components do not yet exist, but the result is that the badly needed components are never developed, since there is never a specific mission designated where they will be used. Then when the mission is flown, its capabilities are greatly reduced due to the lack of the component. For example, NASA is currently budgeting money to develop cryogenic propellant depots in orbit, yet the depots are not included in or integrated into any plans for the BEO missions using the SLS. (This issue was the focus of a letter on September 27 to Administrator Bolden by Rep. Dana Rohrabacher.) Such delays and/or sapping of funds from technology programs for use by the SLS development by Congress allows mission planners to continue to exclude advanced technology solutions from future BEO mission plans.
This is the perennial institutional problem of technology development at the agency because, unlike its predecessor the NACA, technology development doesn’t seem to be viewed as NASA’s job, at least not enough to actually fund it. It’s always chicken and egg in that no one wants to put a new technology on the critical path for a mission, and because no mission requires it, the technology never gets the priority it needs for development. The solution to this is to refocus the agency on tech development, but that doesn’t provide enough pork in the right places.