Do we have some guesses on the minimal infrastructure necessary, on the lunar surface and/or lunar orbit, to start developing and testing NTRs and fission-powered electric/ion drives there? Total tonnage, specific kinds of payloads/ equipment there, are there minable sites for various specific raw materials that happen to be close to each other on Luna so as to have a single hub for this kind of project, etc.
From where I stand, fission + the broad family of electric drives (ion, dipole, plasma rocket, etc, etc) + a lunar/cislunar gateway would basically open up the entire solar system up to Saturn or so, so this is probably where a big part of the push should be happening.
tldr; 10-20-100-1000-10000t; my guess 20t on the moon, 100t at LEO
No, as much as I’m aware(but not 100%) – no one has it.
unfortunately technological information we have(as humanity) presented in the form which makes it hard to be certain what the number is for the case. It is hard to trace the relation what is needed for what and thus we know there may be some number but it even hard tell in order of magnitudes.
We can’t tell it for simpler cases, and not sure someone did that for such specific case.
Generally, stuff is estimated to be 100-1000 ton of equipment.
So as there is no single answer for that, as it depends on the details.
I think one BFR launch is enough, to have some testing facility in LEO – I really wish it would be the first payload of BFR(anyway they will have some dumb payload, then why not the toy factory something like 10t of equipment, 90t of raw materials to play with and develop improve equipment and test recycling and test new designs and processes)
It can be enough for testing different types of electric propulsion, as they aren’t that complex in production(at least some versions of those)
When we get in a nuclear territory – there are even more questions – does it involve processing of fuel, mining of it, seeking for it – each category add a significant chunk of technological libraries/dll’s
if we assume fuel is there to play – again not that many designs were really tested, so it not clear what it takes to produce them, but sure it adds some fields to, so may require specific materials/alloys which adds some BOM specifics and so as a chunk of technologies for their creation, working with them etc.
That minimal number is very sensitive to all sorts of decisions which are made in planning – like which technologies to use, what’s available and stuff.
But generally ability in LEO to reshape materials in different forms – basically the same matter can be used and reused multiple time – it allows to test a lot of stuff.
One of the current goals is to create a model for some simpler processes – to get a number of a capability, and then develop that understanding further in different technologies.
it not that easy, so as there were different attempts in the past with similar or ort relevant goals approaches, in the last 10+ years – not that they got significant traction so as most of them are a fail at the point.
So as the approach is important – there is a difference to think about – let’s get some equipment to the moon and make nuclear engines testing facility with blackjack and bitches or let’s deliver there something which we develop in something and it allows us to do different stuff which includes this and that.
So results can be different if you understand the route from some tech seed to technological state you need for X or delivering that technological state for X just straight away.
If you haven’t seen, you should look and spend time on the video https://www.facebook.com/groups/im42group/permalink/696637320710425/
it does good enough job explaining some important aspects of technological development and does that in human language.
with understanding the road(which not one has atm, at least as public knowledge) I think it is sufficient 10-20t on the moon surface so that in few years to use the results to test multiple stuff, including nuclear technologies if information about them is available to the system.
Having technologies, as a knowledge, formalized in some framework – is one of the huge obstacles atm.