Lunar Surface Rendezvous
One of the ideas I liked from the TeamVision paper (though I think it could and should be taken farther) was Lunar Surface Rendezvous. Now, this term has been used in several different ways, so I’ll define it as a mission architecture where multiple mission elements are landed separately at the same location, instead of all at once. Lunar Surface Rendezvous (LSR) came up several times during the Apollo program, first as a direct competitor to LOR, EOR, and Direct Ascent, and later as a way of enhancing the existing Apollo architecture. One of the ways that Apollo was originally going to be extended (had funding not been cut due to how unaffordable the transportation was) was to use LSR to preland some extra cargo before a manned landing, thus giving the astronauts a lot more tools, a spare rover, additional life support spares and supplies, and other various odds and ends. This would’ve allowed a lot more to be done in a given mission.
TeamVision suggested a form of LSR using prelanded robotic lunar rovers that would work in conjunction with a 2-man landing team to more thoroughly investigate the area of interest. Basically, the robotic rovers would scout out the area in advance, help the astronauts find the areas of most interest, and generally greatly enhance the capabilities of just the astronauts alone. One of the guys who was involved with the Bay Area Moon Society (David Bushman I think?) had given us a presentation about some of the work he was doing with human/robotic exploration teams, and he made a pretty solid case that humans and robots can accomplish a lot more working together than just humans or just robots could.
ESAS plans to use LSR for its base-buildup and operations missions. Basically, once they’re past the sortie phase of exploration (and with the cost of their architecture, that will probably be a very short phase indeed), and have found a base site, the base will be built up over multiple launches. Some landers will bring habitat equipment, others construction equipment, or ISRU stuff, or crews, or what have you. Even the most dyed-in-the-wool HLV fan has to admit that there’s just no way you could launch a complete lunar outpost in one piece. But once you’re down on the surface, deploying stuff, hooking things up, loading and unloading, fitting out hab modules, and all that other stuff becomes a lot easier. Especially if a lot of the work can be done inside. Being on a planetary surface, under the influence of some gravity makes a lot of those construction tasks a lot more similar to terrestrial operations than trying to do similar tasks in zero-g.
But taking the idea further has some merit too. Doug Stanley, in one of his replies on the Q&A thread previously mentioned, explained that the “4 people for 7 days” requirement came mostly from some NASA studies that had been done pre-ESAS on lunar surface operations. As I pointed out in my previous post on 2-man architectures, there’s no reason that all 4 of those people (and all the facilities to support them for 7 days) have to be landed on the same lander.
Why doesn’t NASA land enough stuff to support 4 people for 6 months on a single lander? Or 6 people for a year? Because it would require much too big of a lander, which would cost too much to develop, and way too much to operate. By making the lander smaller, and less capable, but using LSR, ESAS provides a much cheaper approach than trying to do a Battlestar Gallactica scale lunar lander. However, you could see where that logic goes…
And Doug Stanley more or less admitted it. He said that had the 4 people for 7 days edict not been “blessed” by Mike Griffin as one of the ground rules, that EELV based architectures would have traded a lot better compared to the chosen ESAS architecture. And he’s right. All the numbers I’ve run show that you could probably do a reasonable 2-man lunar architecture using stock, or nearly stock EELVs (or EELV equivalents like Falcon IX if it becomes available).
Light Scout Outpost Missions
The numbers I found show that a lander capable of shuttling a two-person capsule from LUNO to the surface and back is also capable of landing (one-way) a fully loaded Sundancer module. By changing the loadout of the Sundancer a bit (and removing non-lunar useful stuff like ACS systems and propulsion systems, etc), and reorienting it towards a two-person setup, you could probably stock enough supplies and equipment to allow those two explorers to stay around for 14 days, or even possibly overnight if you have the right equipment. In other words, you could probably increase the amount of man-days on the lunar surface, while giving yourself more flexibility.
You could call these missions “Light Scout Outpost Missions” (LSO missions?), because they could still be temporary, would cost a lot less than a full-blown 4-man lander, but would still allow enough time to thoroughly explore the nearby environs without having to commit all the money and resources needed to setup a full-scale base. It would be possible to do a lot more of these, even during base build-up, which would allow for a much more thorough exploration of the moon.
Right now with the existing architecture, there’ll likely only be enough money to try checking out 2-3 locales before you have to settle down into a large-scale base. But with LSO missions, you could probably afford not only to scout out more places before setting down too much infrastructure, but you could also afford to continue such LSO sorties during base buildup, and even better, each LSO mission provides some of the seed infrastructure for future bases if economically interesting resources are discovered (like say if Reiner Gamma turns out to have a nickel iron meteorite core left at the bottom of it, or if an area that had Lunar Transient Phenomena turns out to have subselenian gas pockets, or any of a number of other potentially itneresting features that we just don’t know about yet).
And if a sortie site turns out to be very interesting, its easy to incrementally resupply and send crew rotations there to continue exploration. Or you could use the longer time on the surface to do early precursor work on debugging ISRU processes or testing out construction equipment or processes before you commit to larger scale equipment.
The more you look at it, the more you realize that Lunar Surface Rendezvous is not only the way you eventually have to go for serious lunar development and exploration, but that if taken to its logical conclusion, it ends up also being cheaper, more capable, and more flexible than the alternatives.
Latest posts by Jonathan Goff (see all)
- On Avoiding Some of the Mistakes of Apollo - July 21, 2019
- SBIR Proposaling Advice - March 8, 2019
- FISO Telecon Lecture on LEO Propellant Depots for Interplanetary Smallsat Launch - November 28, 2018