Friday, October 14, 2005

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 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.

Sunday, October 09, 2005

Why space?

I suppose every person who begins voicing their opinions about space exploration in a public forum must inevitably answer the question of "Why space?" Sometimes this is more specifically phrased as, "Why spend money on space when there are so many other problems right here on Earth?"

The latter form of the question is a trap, and I recommend that most space advocates try to avoid answering it if possible. The basic premise of the question is that we are somehow actually sending money into space where it will never to be seen again. Nothing could be further from the truth. Every dollar spent on space exploration is being reinvested in our economy. As a result, jobs are created, goods and services are produced, revenue generated, and technological advancements made. I'd like to hear the social conservatives claim that, dollar for dollar, money poured into social causes contributes nearly as much back into the economy. Compared to the perverse amount of money spent on entertainment in this country, I don't think our modest investment in space exploration can be considered socially negligent.

So, I will focus on the more general form of the question, and that is "Why explore space at all?" The answers to this question will vary from one individual to another, but you will typically see one of two kinds of responses.

The first response I refer to as the party line. The party line is usually delivered as a standard reply to those who may not share an enthusiasm for space exploration but they would still like to know why it should be relevant to them. Some examples of the party line are: the human race must spread life into the galaxy or suffer the consequences (extinction, or worse... irrelevance), must explore the frontier, give humanity a fresh start, exploit the vast resources of the solar system, etc. Occasionally, the party line is presented in such a convincing manner that converts are made. Usually though, the person merely smiles and nods and goes back to living their Earth-bound existence without even bothering to look up at the sky and wonder.

The second repsonse is the personal anecdote, and these are most often shared between people who are already have a deep and abiding passion for space and space exploration. Often, this response is much more interesting than any party line because it gives some sense of what space really means to people as individuals rather than as humanity in general. Nearly all of these stories express a strong desire, by individuals, to travel in space or explore the unknown. It is that desire that motivates so many to tackle the hard problems, to risk everything, and to see their vision become a reality. That kind of commitment speaks to the truth that it is in certain humans' nature to push back the edge of knowledge, to seek out untapped resources, and to make a better life for themselves and their posterity wherever possible. (Notice that I did not generalize this statement to encompass all of humanity as one form of the party line would have.)

My personal anecdote is alot less interesting than some others that I have read. This is probably because I'm still in the process of discovering what my true motivation is. I've had a passion for astronomy and space exploration for as long as I can remember. I am incredibly curious about the universe around me, and I've spent my entire life learning about how it works. However, getting to the root of it all - to discover what drives me and what will one day push me to truly fulfill my potential - is a long introspective journey of which I am still in the midst. In the meantime, there is a life to be lived, a universe to be appreciated, and time enough for now.

Saturday, October 08, 2005


In a recent article at the Space Daily website, John Strickland makes the case that there needs to be more reusability built into the in-space assests of the VSE. One of the most important points that he makes in the article is that if NASA proceeds with it's plans to throw away everything but the capsule after each and every mission, leaving no real assets in space, then the program can be canceled at any time in the future when the Congress decides that it no longer wants to fund the effort. However, if you design the in-space assests with reusability in mind, the equation changes dramatically. Rather than pouring money into the development and manufacture of expendable components, the same money becomes an investment in space-based infrastructure. And as we've seen with the shuttle and ISS, once you have a significant investment in infrastructure in place, it becomes much more difficult to kill the project and abandon that investment. Mr. Strickland also make the observation that the Apollo program ended up being based on a largely disposable architecture because that was the quickest way to get men on the moon with the technology available at the time. He points out that we really aren't in any hurry this time. So why not do it right?

The NASA's plan, as it currently stands, is probably in the best interest of NASA and it's contractors. This plan probably represents the best that they can afford to do if they are forced to do it all by themselves. Whether or not they can sustain this program over decades remains to be seen, but it seems pretty clear that if they continue in this manner they will not be able to expand the scope of the program to any significant extent. At the Return to the Moon conference in July, Chris Shank made it clear that NASA can not even afford to go to the moon unless they find a way to spend much less on the ISS. Unfortunately, NASA has not had much success with reducing its costs in the past. And so, we keep returning to the simple fact that as NASA's vangard heads out into space, they must bring the commercial sector along with them.

Personally, I find it hard to believe that any form of space exploration can be sustained without building up some kinda of in-space infrastructure. Exactly what kind of infrastructure is needed is a question which has been occupying my mind for the past few years. I've been contemplating what kinds of infrastructure would need to be put into place to accomplish various missions. I've found that there is alot of overlap in these missions, especially if you break each one up into smaller legs which can be accomplished with a common set of hardware. In future posts in this blog, I would like to begin to explore these smaller missions and the infrastructure that I think would permit them to become self-sustaining. I welcome any constructive comments or feedback anyone has to offer.