13 thoughts on “Back To The Moon, This Time To Stay”

  1. I don’t know if I’d be that bold, Rand. However, why can’t we decouple the lunar lander from the lunar ascent and return. Launch the crew there with one rocket. Launch the ascent and return with another rocket. In the case of the latter, you don’t have to carry a second vehicle or crew at liftoff from Earth. You also don’t have to pack it with supplies, because it only needs enough life support to get back. Bonus, you can make an unmanned version that can be used to send back ore, especially since NASA wants to have a fleet of unmanned robots digging up rock that can’t be sent back to Earth for any usable purpose otherwise.

    1. But that’s not how we did Apollo. The mission architecture has to look like Apollo. Some minor changes might be permissible, such as using a different fatness ratio on the descent stage, or a different aesthetic for the lander’s ascent module, or perhaps a different color scheme. But the basics must be slavishly followed. It will use only one descent engine and Apollo style landing legs, down to the nut, bolt, and strut. The ascent module will sit on top of the descent stage, and it will exit via a side door and a ladder. It will have two windows, but as I said, aesthetically those could be triangular, rectangular, or circular.

      It’s just one of those things, like the way virtually every space show between Star Trek TOS and Battlestar Galactica’s reboot had virtually the same bridge, and the only design choices were whether the captain’s chair in the middle could be flanked by two other chairs or not. The ship is helmed from the console in front of his chair, and the set’s entrance is positioned behind his chair. And that’s how spaceships shall look.

      Similarly, I think the pre-Apollo lunar landing proposals show more fundamental variation and design creativity than the post-Apollo concepts, which often seem to be the same two-stage LOR vehicle from an alternate history where a slightly different group of designers had been working at Grumman. In fact, many of the current proposals look more like the 1969 LEM than some of the designs that directly led it. “Yes, but it’s a much smoother, rounder lander with two big square windows and straighter legs.” “Ah. You found Grumman’s 1962 proposal!”

      Why must the ascent module have sleeping bunks? Because it must. Why does it have two different hatches? Because it must. Why must it have only one descent engine? Because on is the loneliest number? Who knows? That’s how they did Apollo, and that’s how we’re doing the next one.

      Instead, we could just start asking the basic questions.

      Do they need to return?

      Do they need to return on the same vehicle they landed in?

      Do they need to live in the vehicle they landed in?

      They walk around in a space suit all day in hard vacuum, so why do they even need an enclosed ascent vehicle for a low-G, seven and a half minute ride into orbit?

      Side note: Between Apollo 11 and Apollo 14 they cut the required time from ascent to docking about in half with a direct rendezvous mode, docking in about an hour and a half.

      We can probably cut that down dramatically by setting up a direct intercept, since we have infinitely more computer power and ridiculously sophisticated (yet tiny) off-the-shelf aerial radars developed for the growing commercial drone market. If we can intercept ballistic missiles in an atmosphere, we can probably set up a direct rendezvous in a vacuum when we’re controlling both vehicles.

      Similarly, if we can slam land a giant space rocket on a pitching barge in a storm, then in vacuum at 1/6th G we could probably land a descent vehicle accurately enough to make a hard dock with the hatch on top of the previous lander. We could probably land Lego blocks on top of Lego blocks.

      It no longer takes a Saturn V to get two flight computers to the moon, so we don’t have to pack everything onto the one lander that has a flight computer. It might make more sense to land ten different payloads on ten little bitty landers, putting them right where the payloads need to go, instead of sending them packed on one big lander that then has to get unloaded, with each payload laboriously moved to its final destination on a little rover or with an EVA. This would also solves the issue of a giant supply lander having an accident. Instead, maybe one out of ten landers failed, so you don’t get grape jelly that week.

      Of course, some of these basic questions might get put off when we’re still trying to put an American in orbit on an American rocket, but if we don’t ask them soon enough we’ll end up with LEM v1.1, with a touch-screen interface and warmer interior colors.

  2. I think the Antarctic base analogy is very helpful, but for it to be persuasive, I think you need the context and risk levels to be as close as possible. And an initial (well, after a 50 year layoff) lunar expedition like this really is not close to the context or risk level that Amundsen-Scott has, either in 1956, or today.

    You rightly note that the lunar environment is harsher than Antartica (on its worst day); but we could also note that even in its first winter (1956) Amundsen-Scott was a far more robust affair than our first Artemis crew would have – 18 men, including a doctor, several hundred square feet of habitat, and supplies to last through two winters; assurance that the Air Force could and would come at winter’s end, and if they didn’t, the staff could at least attempt to walk out (albeit with some hardship and risk) to McMurdo if all else failed.

    And at worst, the total loss of the Amundsen-Scott crew would have been a blow, but in the context of what were already a score of Antarctic stations and a long record of fatalities in previous Antarctic exploration, a less exceptional one to the public and media, and thus politically survivable for the agency in question.

    But having said all that, the analogy has value for the future. Imagine a scenario where the U.S., China, and perhaps a few other powers (or companies?) have established substantial permanent bases at the lunar poles, and established significant cislunar infrastructure. In such a context, it could be a bearable risk (for NASA, a company or a research institution) to establish a small base on equatorial Farside with no off-planet escape capability, but with ample supplies and a rover which, with skill and a little luck, might at least be theoretically able to reach those bigger polar bases if they absolutely had to, like Mark Watney in The Martian driving cross-country to the Ares V MAV. And the loss of such a crew would hurt, but it would be at worst a bottom-of-the-fold story.

  3. Yes, we need something for the Lunar Ascent module to rendezvous with. It can’t just take off and go home, because think of all the weight waisted on decelerating the extra mass. We must leave extra mass on orbit, because the weight gained from propellant rendezvous burns and docking plus docking gear is minimal. Not to mention the need to duplicate ECLSS and EPS. Plus, we need complexity for the TV drama. Without two ECLSS, how can you create two kinds of CO2 scrubbers?

    Same reason not to launch communication satellites to orbit, so we can still talk about LOS on the dark side of the moon. Oh the drama. And without communication satellites, we won’t even litter the dark side of the moon with unmanned rovers. It will remain pristine lunarscape for future generations to enjoy not seeing.

    By the way, where is NASA plans that include the large moon buggy they have celebrities drive around JSC all the time? They spent all the money developing it, why are they not using it? Surely it wasn’t just a publicity stunt never meant to actually be utilized in space exploration?

  4. I did some math on the multi-mini-lander concept. A single 90-lbf Draco thruster on a 300 lb descent vehicle in LLO should be able to land with a dry weight of 134 lbs. About 100 lbs of that would reasonably be supplies.

    NASA’s 2014 RFP for ISS resupply was for 14,000 to 17,000 kg per year, which can support six people. Averaging 5 CRSS mission manifests, about 12 percent of that mass is crew supplies The rest is science equipment and whatnot. So basic crew supplies for six people would come to about 2,000 kg per year.

    That would require 44 little Draco landers with a total LLO mass of 13,200 lbs. A Falcon 9 FT shouldn’t have too much trouble putting about 8,000 lbs into LLO, so you’re looking at two launches a year for minimal supplies for six people, with the launches costing $100 to $120 million a year, or about $20 million per astronaut per year for the six man outpost. That’s still cheaper than buying seats on a Soyuz, and it isn’t using any heavy lift at all.

    1. An excellent and innovative idea, but me being me, I must nitpick; how could a F9 put anything in LLO? Same for FH: the second stage does not have the ability to remain viable for long enough to do the LLO burn.

      I remember a discussion here about a concept for extending stage duration (I wish I could remember what it was called – it was three letters, and I can’t recall enough to find it) but I don’t know if that could be used on Ker/LOx. If it could, then F9 or FH could definitely hit LLO.

      1. There’s a storable oxidizer that’s a mix of N2O4, NO2, and N2O that can possibly be hypergolic with kerosene.

        *looks for that article again*

        NASA Tech Briefs: Enriched Storable Oxidizers

        But a new propellant combination would cause massive delays.

        So instead, just use the Merlin 1D vacuum engine for TLI, launching a payload with its own integrated propulsion or attached to a separate third stage that uses storable propellants for lunar orbit insertion.

        That would put all the development work on the lunar program, as it would leave the Falcon 9 second stage completely stock, just like it was performing a GTO burn.

        Doing some math, (I might have the wrong numbers for the Falcon 9’s 2nd stage dry mass), and comparing those to its GTO payload capability, I think a F9 FT on a re-usable mission could put a payload of almost 9,000 lbs (4100 kg) on a 3150 m/sec TLI burn.

        Then you do an 890 m/sec LOI burn with a hypergolic engine with 310 ISP, which takes a mass ratio of 1.34. The payload in lunar orbit, along with that third stage, is 6,730 lbs (3,060 kg). Assuming 730 lbs of that is the mass of the third stage, that leaves you with 6,000 lbs worth of mini-landers. They each weigh 300 lbs, so you have 20 to drop to the surface, each on a regular Draco thruster and delivering 100 lbs of supplies. So that comes to 2,000 lbs delivered. According to the rough ISS resupply calculation above, they need 4,400 lbs per year to stay hearty and healthy, so two Falcon 9 FT re-usable launches will just about do it.

        If they cut the crew of six down to five by staging an accident, then basic resupply on two missions a year shouldn’t be any problem at all.

        However, I’m not sure that “ISS crew supplies” includes breathable oxygen or drinkable water, in which case they’ll need to stage a lot more accidents a lot sooner. I hope my numbers aren’t based on just toothpaste, fresh socks, dehydrated meat patties, and toilet paper, but I’m sure someone would run the numbers again if the idea resurfaces.

  5. In fact, the marginal cost of such a mission might be sufficiently low as to allow multiple habitats and crews in different locations, with regular crew rotations once a round-trip system has been developed over the next couple of years.

    I would like to see this but if the cost of a Gateway is too high, why would putting a similar scale of infrastructure on the lunar surface be cheaper, or an acceptable cost? Gateway is supposed to enable this happening anyway but why does cost suddenly not become an issue when we start talking about a lunar base much less several lunar bases?

    Which parts of a cislunar architecture be thrown away and how does that cost add up over the years?

    The funding arguments are all a bit of a joke. The government does yearly budgets and the numbers change a bit from year to year. It is foolish to think that there would be some certain number that NASA would get in ten years or that the number requested today would be the number they need later. No matter what NASA does to expand its activities, it will cost a lot of money. The dollar amount is less important than whether or not congress will support it. There are many ways congress can find the money and while it is slightly possible they could cut something, there is a higher chance they will just debt finance if the program is one that they support.

    Simply getting someone to the moon was relatively easy, even then:

    Same with now and comments sections are filled with ways to get humans on the Moon quickly but not much consideration is paid to anything that happens after that. When consideration is paid, it is usually about things that a rather far down the line than the immediacy of what comes next.

    Step 1: Land humans on the Moon.
    Step 2:
    Step 3:
    Step 4:
    Step 5: Fuel depots, mining, tourists, 3D printed bases, beamed power, ect (We are here in the discussion)

    1. Why would a lunar base be cheaper than an a station in lunar orbit?

      One reason is proper radiation shielding. To actually maintain a permanent base outside the Van Allen belt, it must be shielded against the occasional x-class solar far and the like. Until a crew can survive the really bad days when a major storm erupts, they’re just gambling on the weather.

      The cheapest way to get a thick shielding mass is to burrow in to the lunar surface, taking advantage of all the free dirt. Almost all the serious ideas for setting up a permanent lunar base involve sending the first habitat and burying it, either before the astronauts arrive or as task one for them.

      All the proposals for permanent orbital structures at the Lagrange points, such as O’Neill colonies, depend on using lunar regolith for radiation shielding.

      A lunar orbital station that skips that important step is a canoe floating in the ocean. You don’t want it manned when a major storm hits.

  6. Applause to wodun, above.

    Imagine a toddler, acting with all the grace, self discipline, and judgment two year olds are so well known for, moving through this http://images.spaceref.com/news/2011/ooiss026e021187.jpg
    like a bird through a forest.

    Talk to me about space, or heck, even lunar colonization, instead of exploration, “to stay”, when we start sending newlywed couples to the up-and-out with a grub stake and NO RETURN TICKET.

  7. Rand,
    I’ve been a fan of an approach like this for almost 20yrs now. Reminds me of the old Prometheus Downport Project. Crap, that was 20yrs ago… Maybe I should do a writeup on Selenian Boondocks.


  8. There was a book once “The Pilgrim Project” by Hank Searles later made into a movie “Countdown” about beating the Russians to the Moon by sending one person to stay for a year until the return vehicle could be developed.

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