I definitely think that lunar markets can play a role in making RLVs feasible, but those lunar markets will only be feasible as the transportation architecture becomes sufficiently affordable. I think it can reach that point of economic feasibility before RLVs are here, but only barely. And there’s no chance in heck that it will reach the point of economic feasibility using a closed, government-developed architecture like Ares.

~Jon

It takes about half the delta-V and twice the amount of trip time to get to EML2, via a powered lunar swingby, as it takes to get to EML1, because LEO-EML1 trajectories can’t take advantage of powered lunar swingbys.

8 days vs. 4 days for half the DV. For propellant resupply of an L-point “Gateway” it would seem to argue for EML2 in my opinion.

The other collinear L-point (L3) is completely opposite from the Moon and no use at all, for what I can tell.

The equilateral L-points (L4 and L5) are quasi-stable, but require larger DVs to get there than L1, and large DVs to leave from there and go to the Moon along with long trip times.

If NASA can afford to do RLV work while also establishing a lunar base with what we have, that is fine and good. But, if you have to choose, choose the base first as the market that justifies an RLV, then invest in your RLV.

Actually, I am rather happy with the current situation. COTS and the Air Force are developing new launch vehicles, some of which are RLVs, while NASA should be using EELVs to establish the most rudimentary lunar base (or asteroid base) as the market these new vehicles will need. Where we’ve gone wrong — as just about everyone here seems to agree with greater or lessor fervor — is in NASA wasting their money on a new launch vehicle that is in no way a step forward and (if Anonymous is right) won’t even get us to the moon.

I think we agree, though obviously, our emphasis is quite different. I want to start as small as possible without trying to simultaneously execute too many projects. NASA can’t even develop the Ares-1 by itself, let alone develop a lunar base, uprated EELVs, RLVs, depots, deep space stages, and all the rest. Better to let NASA concentrate on the end market, like they’ve done with the Space Station (as Dennis describes above), and let the commercial people develop the second generation transportation, and the Air Force invest in the long-range RLV technology.

— Donald

Vanilla,

I stand corrected. I understand that there are advantages & disadvantages to the various Earth-Moon lagrange points, and I believe it is an open question about which one is best.

I meant to say “LEO and Earth-Moon lagrange point depots”.

That said, I am open to being shown that L2, or any other lagrange point, is optimal under certain conditions.

– Al

…I am not sure why we everybody is arguing about this.

Well, I would argue that lunar L2 is a better location for this propellant depot, but I agree overall that if we aren’t working towards reducing the costs of lunar activities, we’re wasting our time.

I assert that you can have the best parts of all these strategic thrusts, and create a “win, win” outcome for everybody here, if you set up the plan and approach correctly.

You can have an aggressive NASA “human lunar base development” program, and utilize existing EELVs now, and plug in RLVs later (when they come on line, and after they have PROVEN they are effective and low cost). You could call this “spiral development”, which is what Admiral Steidle proposed.

The architecture, of course, is to develop an Earth-Moon transportation system that explicitly designs in “LEO and L1 propellant depots”, and lunar ISRU. You start with EELVs (and the existing launch vehicles of other nations … so the architecuture inherently designs in international participation … this is win-win-win), and then you develop RLVs in parallel.

When RLVs show up, you get a large and almost immediate benefit to the lunar base. Yet, you are not dependent on them to start development of the lunar base, or to establish the initial lunar base (which appears to be Mr. Wingo’s primary concern).

In addition, by designing a depot-based architecture, you are designing your system to expand the market demand for commercial space transportation (which appears to be Donald Robertson’s issue.) You also built in competition to your approach, creating market-based incentives to lower space transportation costs. You have NOT locked yourself into any one system (e.g., Ares 1/5), and eliminated competition for this part of the market demand. (The moment that the Ares 1/5 come into existence, the people who work on them, and their politicians will fight against any competing approach.)

The LEO propellant delivery business becomes the next big market beyond ISS, and the customer for the LEO propellant business is the lunar base.

This appears to be a “win, win, win” to me (national security benefits, commercial benefits, and a more economically sustainable lunar architecture). If you add the ability to easily plug in international partners into the system, at an early date, you could argue this a “win, win, win, win”.

If you add in the savings you get — early in the program — from using EELVs instead of building the Ares 1/5, that can be applied to developing the LSAM (and other lunar systems) — which is one thing our friend Anonymous cares about — you could call this a “win, win, win, win, win”.

If then add in that it lowers the barriers to lunar ISRU (because you are building propellant depots) and that it frees up early funding that can be used to develop ISRU lunar systems … you get my point.

I am not sure why we everybody is arguing about this.

– Al

Assuming that 1600 lb mining machine works the first time, of course. I would expect there to be a string of not-quite-working machines before all the bugs are worked out.

Well in business often one segement often subsidizes the startup costs of a follow on venture. The principal that allows something like I am describing starts at ISS and expands outwards from there. That is if we pretend that NASA does not exist in its exploration program. The nice thing is that we do have ISS and we do know what it is capable of (when the international modules and the power systems are finalized then ISS is going to be an awesome platform for orbital assembly operations) and how to leverage it. The problem is that it is such a divergence from today’s way of doing business that it is difficult to convince financiers of its merits. it is it’s own form of circular argument. If it was soo good to do this why hasen’t anyone done it? The answer is that ISS is still new, acccess is anything but assured. That is why the COTS guys are important beyond the Russians. Unfortunately the success of COTS is far from assured. I may be getting involved to help with that but if we can send payloads there, then we can move forward. My European business (Orbital Satellite Services Limited) is moving forward with GEO satellite serivces which is another link in the chain.

The ultimate goal is what I call Ubiquitious Space Operations (USO), which opens space beyond LEO to development. We have to start thinking different about space, it is not all getting to orbit and there is much that can be accomplished to build markets that will enable the financial markets to see that the risk inherent in building a reusable system (market risk not technical) are being retired. It has been the market risk that has done the most to impede the development of RLV’s. This continues with COTS as the difficulty that Kistler has today in obtaining their matching funds is directly tied to market risk.

Until these things penetrates the bone marrow of those who want RLV’s, we will never have RLV’s.

A ME system can produce hundreds of pounds of materials per day for that size package. Of course it requires service and it will be designed for it.

Good question. There are a lot of caveats here but the general principle is that the commercial development is is parallel and in concert with NASA’s lunar efforts. As soon as this begins then even with the ESAS architecture’s limitations the beginnings of lunar commerce can happen. If you like I can provide a link to a contract paper I did for NASA Langley on this subject.