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[Lyn Farel]

Definitly.

[orange]

Space is fun, and I love space, but I think this captures it a bit.

[Esna Pitoojee]

Hrm. I did ramble a bit in my initial post, which I apologize for. Perhaps what I was more getting at is that to get to the moon -quickly- requires a single-launch-to-moon concept, not waiting weeks or months to put something together in space through several launches.

However, the current crop of private companies and most rockets available for national or private use do not have the lifting capacity of previously used or trialed for single-launch-to-moon rockets - so, they're stuck with the assembling something in space, unless they develop a new, gigantihueg rocket.

I would then say that the true "tortoise and hare" race here is not between specific nations, but between those that would use existing technology to build something slowly and those that would develop an entirely new rocket that would be able to get people to the moon straight from a single launch.

Right now the US is the only one even appearing to look at the latter concept, but since we've gone through something like 5 rocket programs in the past decade, that's not saying we're far along in the development.

[orange]

In my not so humble opinion, if we want to go to stay (or keep going) you assemble in space over a series of launches and reuse the in-space hardware extensively.   This is regardless of whether you have a big rocket (Saturn V or SLS) or just a bunch of Falcon 9s.

[Nicoletta Mithra]

I think the Chinese are working on carrier systems to reach the moon as well, Esna.

As for the US-American space program:

[Louella Dougans]

From the pic on the website here:
[spoiler][/spoiler]

It looks like they're looking at Four rockets per mission. (possibly more)

It's blurry, but I think I can make out the names.

An Atlas V launches, with the "LTV",  (Lunar Transfer Vehicle?), and somehow the LTV is refuelled in orbit.
A Falcon launches, carrying the Lander.
The LTV and Lander rendezvous in Earth Orbit, and transfer to the Moon, leaving the lander in orbit of the Moon.

A 2nd Atlas V launches, with a 2nd LTV, and the LTV is refuelled in orbit again.
A 2nd Falcon launches, carrying the crew vehicle.
Crew vehicle and LTV rendezvous in Earth Orbit, transfer to the Moon.

The Lander and Crew vehicle rendezvous in Lunar orbit, the lander goes down to the surface, comes back up, rendezvous with the Crew vehicle again, and the Crew Vehicle transfers back to Earth, and the crew capsule seperates, splashes down and is recovered.

4+ launches for that first mission. (unclear on how the LTVs are refuelled).

Not sure on how much of that could be re-used. If the Lander descends and ascends complete, then it would just need refuelled in Lunar orbit again, wouldn't it ? The LTVs appear to be discarded, as is much of the crew vehicle.

4 launches, 6 craft rendezvous, 1 recovery, looks like a lot more potential for delays and problems, solar flares and whatnots.

Possibly also spacejunk proliferation too, depending on where those LTVs and other bits go, the LTVs look like being discarded in Lunar space.

[orange]

[spoiler][/spoiler]

Above is a better quality infographic from Space.com, which is based on an interpretation of Golden Spike Company (GSC)'s 3 Dec paper (off their website).

I did the first order calculations on whether a Falcon Heavy can lob a Dragon around the Moon and safely return it to Earth.  It can and it is something GSC looked at in their paper.   Falcon Heavy hasn't flown yet, so they are not relying on it.  Essentially it brings it down to 2 launches instead of 4.

I think the LTVs might be reused, depending on how much reuse they want to get out of them.

I would pursue a different architecture, but I would also have it be an initial "customer" for fuel depots.

[Mithfindel]

Just a few things I could note on the top of my head.

The Lunar Transfer Vehicle in that example would be essentially a booster stage? Not sure if that would need to be "refueled" in the orbit, if it comes with its own fuel for the journey to the moon. Of course, if it had the fuel for a two-way trip then it might be reuseable. Though the return trip, specially if you need to return only the crew module, requires very little fuel, so it comes down to calculating which is cheaper, making a reuseable, refuelable LTV capable of a two-way trip, launching it to the orbit, and then launching refuel missions, or launching a new LTV for every module.

While I admit re-using the LTV sounds elegant, I doubt it would be cheaper than using simpler one-way boosters for an already very complex plan. Difference in boost from Moon to back probably isn't that much, so the main cost is the cost of designing and launching refuel missions. If it costs almost as much to launch the fuel (specially if the refuel vehicle cannot be reused) than launching a LTV, it probably isn't worth it economically. Sure, the refuel vehicle can probably be relatively "flimsy" compared to the LTV, but that's still extra weight. Also, while space vehicles are probably engineered with large marginals, you'd eventually need to service and repair it, which would then require a separate mission (or a new LTV).

Alternatively, there would need to be a way to refuel in the Moon (& supply fuel from the relatively small gravity well of the Moon), but having a base there is way beyond this plan. Repair on orbit would probably also be easier with a properly equipped station, but that too is way beyond this plan.

Finally, the reuse of the lander depends on whether it is made to be serviced in Moon orbit and reused, and more importantly, whether it even returns whole or whether part of it stays on the Moon as a kind of a launch platform (discarding landing gear meaning again possible fuel savings due to reduced weight, specially if the module isn't reuseable).