>>10431369Also, regardless of when it launches, it bears mentioning that each launch of the SLS is expected to cost $500M (logistical support included). F9 and FH on the other hand are around 100-120M as I understand it. Also, you're throwing away every single stage up to the capsule with each launch. That's enormously expensive per launch. Finally, factoring in build, testing, and certification, it seems like the turnaround on building of a new SLS Block vehicle is anywhere from 12-14 months, perhaps longer; making re-flight differences considerable.
>>10431348I'm sure you'll show me.
>>10431287You could arguably make concrete from lunar regolith, though you'd have to do it in a sealed chamber--because over billions of years, its turned into this razor fine dust--far smaller a grain than what we produce on earth. Biggest challenge will come from three things:
1. Access to water ice
2. Access to electricity in quantifiable amounts that can be dedicated to construction material production
3. Access to a 3D printer that can operate in the vacuum of space and use the lunar concrete that can be applied to the inner surface of a tunnel and MOST IMPORTANTLY, can be dried so in the vacuum of space somehow so that it will harden and form the protective shell.
Unironically, I imagine they'll produce the concrete in a sealed environment and then feed that into a machine that produces lunar bricks. Then use these bricks to create a sealed shell in a tunnel/lava tube; inside of which you'd deploy the inflatable habitat with reinforced segmented struts.
The problem I foresee with lava tubes is that you'd have to dedicate infrastructure to mapping out the interior, doing seismic studies to determine viability as a habitable space, doing material analysis to figure out what the walls are made up of and whether they can be trusted to not cave in on them if there's a material impact somewhere on the moon near to the habitat, etc. All of which costs time, money, and O2 1/2
