Foam steel. You take foam and you aerate it in zero gravity. Not a new technology.
The University of Alabama at Huntsville centre for the commercial development of space specialising in materials science research did a test flight in the third month of 1989 from White Sands Missile Range aboard a Starfire rocket (their payload was called Consort 1). They had a device to melt the steel as the rocket went up, and once it was in microgravity at the top of the parabolic arc, they foamed the steel with pressurised air. Pretty cool stuff my friend. I think they did six or so additional flights with the same experimental payload. The second flight was a mess, though, Pete Armitage sounded foolish giving the voice of launch control. Just about the time he was saying "looks like another perfect flight" the thing was blown by range safety, de-thrusting the booster. The payload was recovered though. I know, I was logistics manager for the first three flights, though I left the company the week after the second flight (11th month of 1989). Anyway, something to look into.
Foam steel has a lot of the tensile strength properties of steel but a lot less mass. Which could be significant to your project. There's more than enough nickel iron in the main belt asteroids to do what you want, imo.
Jerry Pournelle came up with an interesting idea. You take a long thin asteroid, drill a hole down the centreline of the long axis. Put bags of water all down the middle. Then you spin it up and put it in the focus of a very large mirror. The mirror focuses the light of the sun and the nickel iron asteroid heats up. Eventually it becomes molten iron and when the heat hits the water bags, they explode into steam. Boom, a big hollow tube. Takes some modelling and experimentation to get the process right, but you get the idea.
Stardust provided a few examples, along with the equations and a rundown of the processes, for some fascinating materials. We have apparently come a long way since 1989. Anything we use that's appropriate for a project as large as the Moon requires iron as the catalyst, at the least. I'm talking the latest in applied engineering here though.
The fascinating part of Stardust for me was how helpful it actually was. The conversational interface allows not only for education at all levels of advancement, but also the honing of one's ideas and what to do to apply them. From general outlining to getting way down in the nuts and bolts of applied science and engineering. Keep in mind; the LLM was still very accurate when I did this experiment.
Its seeming need to "help" and the user's ability to manipulate the LLM conversationally is an extremely powerful tool for someone who is already intelligent. The ease with which Stardust could move from high level administrative concepts to deeper technical concepts all via conversation was impressive to me. I used my OpenAI account and did everything directly through them using their platform. This was not the parsed-out versions of LLMs we're flooded with today.
Foam steel. You take foam and you aerate it in zero gravity. Not a new technology.
The University of Alabama at Huntsville centre for the commercial development of space specialising in materials science research did a test flight in the third month of 1989 from White Sands Missile Range aboard a Starfire rocket (their payload was called Consort 1). They had a device to melt the steel as the rocket went up, and once it was in microgravity at the top of the parabolic arc, they foamed the steel with pressurised air. Pretty cool stuff my friend. I think they did six or so additional flights with the same experimental payload. The second flight was a mess, though, Pete Armitage sounded foolish giving the voice of launch control. Just about the time he was saying "looks like another perfect flight" the thing was blown by range safety, de-thrusting the booster. The payload was recovered though. I know, I was logistics manager for the first three flights, though I left the company the week after the second flight (11th month of 1989). Anyway, something to look into.
Foam steel has a lot of the tensile strength properties of steel but a lot less mass. Which could be significant to your project. There's more than enough nickel iron in the main belt asteroids to do what you want, imo.
Jerry Pournelle came up with an interesting idea. You take a long thin asteroid, drill a hole down the centreline of the long axis. Put bags of water all down the middle. Then you spin it up and put it in the focus of a very large mirror. The mirror focuses the light of the sun and the nickel iron asteroid heats up. Eventually it becomes molten iron and when the heat hits the water bags, they explode into steam. Boom, a big hollow tube. Takes some modelling and experimentation to get the process right, but you get the idea.
Stardust provided a few examples, along with the equations and a rundown of the processes, for some fascinating materials. We have apparently come a long way since 1989. Anything we use that's appropriate for a project as large as the Moon requires iron as the catalyst, at the least. I'm talking the latest in applied engineering here though.
The fascinating part of Stardust for me was how helpful it actually was. The conversational interface allows not only for education at all levels of advancement, but also the honing of one's ideas and what to do to apply them. From general outlining to getting way down in the nuts and bolts of applied science and engineering. Keep in mind; the LLM was still very accurate when I did this experiment.
Its seeming need to "help" and the user's ability to manipulate the LLM conversationally is an extremely powerful tool for someone who is already intelligent. The ease with which Stardust could move from high level administrative concepts to deeper technical concepts all via conversation was impressive to me. I used my OpenAI account and did everything directly through them using their platform. This was not the parsed-out versions of LLMs we're flooded with today.
The great and terrible administrative assistant!