More ESAS details
Keith Cowing's review of a presentation of the new Exploration Architecture to the National Academy of Sciences provides alot of what has been sorely lacking from the main stream media (as well as many of alt.space blogs), and that is any information about how NASA arrived at this particular design and what they intend to do with their bright and shiny new Lunar Exploration Program (TM). In addition to giving more details about the architecture itself, NASA also provided it's justification for returning to the moon in the form of three generic objectives to be attained:
- Basic lunar science
- Resource extraction and utilization
- Testbed for components of what may become the Mars exploration architecture
The article mentions a few times that they have not developed any specific plans for a Mars exploration architcture, yet by sizing the components as they have, they are designing in the capacity for the hardware to be scaled up for possible use in the Mars exploration architecture. While I applaud them for their forward thinking, the missions to Mars will not even be on the drawing board for another ten years and are not likely to be carried out for another ten years after that. I only hope that these future requirements do not impose too much additional expense and complexity in the near term on components being developed for the Lunar missions. For instance, how much sooner do you think we could return to the moon if we didn't have to wait for the shuttle-derived heavy lifter to come online? How much sooner could we field a replacement for the shuttle if we didn't have to wait for the stick to be developed and went instead with a capsule on an EELV?
I'm still not impressed with the lack of development of in-space infrastructure. As I noted in an earlier post, it seems like the initial lunar exploration (or Lunar Sorties as their calling them) will be rather wasteful in terms of the amount of hardware being thrown away on each mission. I did however see a faint glimmer of hope from the mention that they are considering leaving behind a large portion of the habitat as a functional unit.
Connolly noted that thought is also being given to leaving part of the crew compartment [of the lunar lander] behind as part of a cached resource that could later be used for a lunar base. Such an approach is currently referred to by NASA as an "Incremental Build Approach".If an autonomous ISRU unit is incorporated into each of these modules, then oxygen could be cracked from the regolith and used to resupply the habitat with breathable air indefinitely (assuming carbon-dioxide removal can be maintained as well). The habitats could then be used on later missions as remote outposts or even emergency shelters should they be required. If these stations were located in sufficiently close proximity to one another, this would vastly increase the range over which subsequent crews would be able to roam. A similar strategy for Mars exploration was put forth by Zubrin in The Case for Mars.
Overall, I'm still not entirely sold on the new Lunar Exploration Architecture. I think there are other ways to accomplish the same goals that would have the added benefit of actually allowing entities other than NASA to begin exploring cislunar space on their own dime. These new details though give a much needed boost to some of the rationale behind the design decisions made by NASA. I'd just hate to see this Apollo 2.0 prematurely canceled as was its predecessor.
If you look back at some of the plans NASA had for advanced Apollo missions, you will see that similar thinking was followed back then. Alas, Apollo was ended just as it was about to pass the threshold between quick sorties and true lunar expeditions.