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> you honestly don't think ten years of strong-willed national (or even international) effort could get us a robot capable of digging holes? Yes, I do think th

> you honestly don't think ten years of strong-willed national (or even international) effort could get us a robot capable of digging holes? Yes, I do think that. Because there is a big difference between an exploratory vehicle that carries a number of scientific instruments and can be powered by a few solar panels or a small nuclear battery... ...and these beautys: https://en.wikipedia.org/wiki/Tunnel_boring_machine https://en.wikipedia.org/wiki/Tunnel_boring_machine Just for comparisons sake: Perseverances MMRTG provides 110 watts of power. A single metric horsepower is 735.5 watts. I leave looking up the power requirements of even a small machine that would be capable of digging habitats into the martian bedrock, as an exercise to the reader.

feoren 3y ago
I agree it's not realistic to send a full tunnel boring machine, drilling out 200 to 700 meters per week for subways and highways, to Mars in the next 10 years. Such a thing would have to be assembled on Mars with advanced industry already in place. I vehemently disagree that we need a 700 meter/week behemoth, sized for heavy rail, to dig out a habitat for one or two dozen humans. I'm imagining something more like a small-ish Roadheader[1], two to four times larger than Perseverance. It would either need to be Diesel powered (yes, shipping the diesel would suck, but it doesn't need to run forever) or we'd need a small solar farm and a couple Tesla batteries powering the thing (we probably want that anyway, for our habitat). It would take months to dig out a cave large enough for 10 to 20 humans, and there are hundreds of other problems to solve to actually turn a small, potentially unstable Martian cave into a livable habitat. We know the first steps will be slow; that's OK. Besides, we have a decade of engineering to refine the design. Don't underestimate humans. [1] https://en.wikipedia.org/wiki/Roadheader https://en.wikipedia.org/wiki/Roadheader
- usrbinbash 3y ago
  Okay, let's talk about that. A (very) small roadheader starts at around 8 metric tonnes, and requires around 20kW of power...just for operating the cutting head. And that's a really small one. Again, for comparison, Perseverance: 1025kg, 110W of power > It would either need to be Diesel powered That would be a neat trick on a planet with an atmospheric pressure of 610 pascals, where oxygen registers barely above a trace element. > or we'd need a small solar farm Or maybe a not so small one. Using Tesla solar panels https://www.tesla.com/solarpanels https://www.tesla.com/solarpanels as a reference point, they produce up to 400W and are just shy of 2m². That's on Earth. Solar irradiance on Mars is 59% of Earths, so these panels will probably produce ~240W apiece. So to meet the energy requirements of even a small roadheader, we need 83 of these panels, each of which is ~21.5kg in mass, so a total of 1.784t in solar panels alone. Note, that is without cabling, inverters, electronics, spare panels, support structures, etc. ... or the batteries for that matter. Production numbers are also for peak sunlight conditions on Mars, so best-case daylight during the martian summer, and no dust storms. So depending on how heavy the batteries are, I reckon we are already looking at around 12-14 tons of equipment, just for digging with a single machine. And that doesn't include any prefabricated parts, spare parts, airlocks, other heavy machinery, support beams, other auxilliary materials.... I mean, these roadheaders will require new drill heads every now and then, won't they? What's the payload capacity of our current space ship designs again? Because... > It would take months to dig out a cave large enough for 10 to 20 humans, ...we need food and water and medical supplies and power and space suits, and a lot of other things for all these people. Oh, and habitats, because they will need somewhere to live during all these months bevore the cave is ready.
  - feoren 3y ago
    Good point about running a diesel engine on Mars. > So depending on how heavy the batteries are, I reckon we are already looking at around 12-14 tons of equipment, just for digging with a single machine. So you're saying a single Starship could ferry 7 to 8 full rigs? 14 tons of payload is not a big deal right now, much less with 10 years of project-of-national-importance funding. Let's send 2 (one backup) along with lots of other nice goodies for setting up shop then. > So to meet the energy requirements of even a small roadheader, we need 83 of these panels, each of which is ~21.5kg in mass, so a total of 1.784t in solar panels alone. > ... I mean, these roadheaders will require new drill heads every now and then, won't they? 1.8t in solar panels and some extra for new drill heads is really not that much tonnage for the kind of project we're talking about. And remember, we're re-using all this electrical infrastructure for our habitat. > ...we need food and water and medical supplies and power and space suits, and a lot of other things for all these people. Oh, and habitats, because they will need somewhere to live during all these months bevore the cave is ready. They live on Earth before the cave is ready. Why send them at the same time? Remember: the original point was that digging a habitat-sized cave on Mars is really not the hard part here, and something we could accomplish within 10 years if we wanted to. 15 to 20 tons of payload and some moderate engineering challenges have not really disproved that notion. Yes, there are plenty of other hard parts.
    - usrbinbash 3y ago
      > So you're saying a single Starship could ferry 7 to 8 full rigs? https://en.wikipedia.org/wiki/SpaceX_Starship_flight_tests https://en.wikipedia.org/wiki/SpaceX_Starship_flight_tests > 14 tons of payload is not a big deal right now Correct...to low earth orbit, it isn't. But we aren't talking about LEO deployment here. We are talking about a flight to Mars. And we won't be deploying that paylod in space, we have to land it, with the ship, with zero support structures on the ground. > They live on Earth before the cave is ready. Why send them at the same time? Then please show me the robotic infrastructure that is capable, with no pre-existing support structures, of building a sealed habitat, after self-unloading from a landed spaceship, and self-assembling itself from it's packaged form. All steps have to be done with no human help on site. Show me that this works here on Earth. And then show me that same thing, but this time, any remote control has a 6-minute delay (and that's still generous, because 3 light minutes is the lowest possible distance between the 2 planets), and it has to be done at in an antarctic dry valley. Then we can talk about that working on Mars.
notfish 3y ago
You could totally just dig a 1 meter deep hole with a fancy bulldozer, then plop down a prefabbed house and bury it Hell, you could even have humans do the digging assisted by machines and just live on the surface for the first few months while they build
- usrbinbash 3y ago
  > You could totally just dig a 1 meter deep hole with a fancy bulldozer, then plop down a prefabbed house and bury it Yes, and that "prefabbed house", that is sturdy enough that we can "bury it" under a pile of rock [1] thick enough to provide adequate protection from cosmic radiation, where does that come from? How much mass is that? How is that mass transported to mars? What machines and tools are required to assemble it there, and how much mass are those? How is the energy for these tools provided? [1]: Just to be clear what a pile we are talking about here: If we used the water-shield method, it would require 5m of water for a 50% reduction in radiation intensity.

feoren 3y ago

I agree it's not realistic to send a full tunnel boring machine, drilling out 200 to 700 meters per week for subways and highways, to Mars in the next 10 years. Such a thing would have to be assembled on Mars with advanced industry already in place. I vehemently disagree that we need a 700 meter/week behemoth, sized for heavy rail, to dig out a habitat for one or two dozen humans. I'm imagining something more like a small-ish Roadheader[1], two to four times larger than Perseverance. It would either need to be Diesel powered (yes, shipping the diesel would suck, but it doesn't need to run forever) or we'd need a small solar farm and a couple Tesla batteries powering the thing (we probably want that anyway, for our habitat). It would take months to dig out a cave large enough for 10 to 20 humans, and there are hundreds of other problems to solve to actually turn a small, potentially unstable Martian cave into a livable habitat. We know the first steps will be slow; that's OK. Besides, we have a decade of engineering to refine the design. Don't underestimate humans. [1] https://en.wikipedia.org/wiki/Roadheader https://en.wikipedia.org/wiki/Roadheader

usrbinbash 3y ago
Okay, let's talk about that. A (very) small roadheader starts at around 8 metric tonnes, and requires around 20kW of power...just for operating the cutting head. And that's a really small one. Again, for comparison, Perseverance: 1025kg, 110W of power > It would either need to be Diesel powered That would be a neat trick on a planet with an atmospheric pressure of 610 pascals, where oxygen registers barely above a trace element. > or we'd need a small solar farm Or maybe a not so small one. Using Tesla solar panels https://www.tesla.com/solarpanels https://www.tesla.com/solarpanels as a reference point, they produce up to 400W and are just shy of 2m². That's on Earth. Solar irradiance on Mars is 59% of Earths, so these panels will probably produce ~240W apiece. So to meet the energy requirements of even a small roadheader, we need 83 of these panels, each of which is ~21.5kg in mass, so a total of 1.784t in solar panels alone. Note, that is without cabling, inverters, electronics, spare panels, support structures, etc. ... or the batteries for that matter. Production numbers are also for peak sunlight conditions on Mars, so best-case daylight during the martian summer, and no dust storms. So depending on how heavy the batteries are, I reckon we are already looking at around 12-14 tons of equipment, just for digging with a single machine. And that doesn't include any prefabricated parts, spare parts, airlocks, other heavy machinery, support beams, other auxilliary materials.... I mean, these roadheaders will require new drill heads every now and then, won't they? What's the payload capacity of our current space ship designs again? Because... > It would take months to dig out a cave large enough for 10 to 20 humans, ...we need food and water and medical supplies and power and space suits, and a lot of other things for all these people. Oh, and habitats, because they will need somewhere to live during all these months bevore the cave is ready.
- feoren 3y ago
  Good point about running a diesel engine on Mars. > So depending on how heavy the batteries are, I reckon we are already looking at around 12-14 tons of equipment, just for digging with a single machine. So you're saying a single Starship could ferry 7 to 8 full rigs? 14 tons of payload is not a big deal right now, much less with 10 years of project-of-national-importance funding. Let's send 2 (one backup) along with lots of other nice goodies for setting up shop then. > So to meet the energy requirements of even a small roadheader, we need 83 of these panels, each of which is ~21.5kg in mass, so a total of 1.784t in solar panels alone. > ... I mean, these roadheaders will require new drill heads every now and then, won't they? 1.8t in solar panels and some extra for new drill heads is really not that much tonnage for the kind of project we're talking about. And remember, we're re-using all this electrical infrastructure for our habitat. > ...we need food and water and medical supplies and power and space suits, and a lot of other things for all these people. Oh, and habitats, because they will need somewhere to live during all these months bevore the cave is ready. They live on Earth before the cave is ready. Why send them at the same time? Remember: the original point was that digging a habitat-sized cave on Mars is really not the hard part here, and something we could accomplish within 10 years if we wanted to. 15 to 20 tons of payload and some moderate engineering challenges have not really disproved that notion. Yes, there are plenty of other hard parts.
  - usrbinbash 3y ago
    > So you're saying a single Starship could ferry 7 to 8 full rigs? https://en.wikipedia.org/wiki/SpaceX_Starship_flight_tests https://en.wikipedia.org/wiki/SpaceX_Starship_flight_tests > 14 tons of payload is not a big deal right now Correct...to low earth orbit, it isn't. But we aren't talking about LEO deployment here. We are talking about a flight to Mars. And we won't be deploying that paylod in space, we have to land it, with the ship, with zero support structures on the ground. > They live on Earth before the cave is ready. Why send them at the same time? Then please show me the robotic infrastructure that is capable, with no pre-existing support structures, of building a sealed habitat, after self-unloading from a landed spaceship, and self-assembling itself from it's packaged form. All steps have to be done with no human help on site. Show me that this works here on Earth. And then show me that same thing, but this time, any remote control has a 6-minute delay (and that's still generous, because 3 light minutes is the lowest possible distance between the 2 planets), and it has to be done at in an antarctic dry valley. Then we can talk about that working on Mars.

notfish 3y ago

You could totally just dig a 1 meter deep hole with a fancy bulldozer, then plop down a prefabbed house and bury it Hell, you could even have humans do the digging assisted by machines and just live on the surface for the first few months while they build

usrbinbash 3y ago
> You could totally just dig a 1 meter deep hole with a fancy bulldozer, then plop down a prefabbed house and bury it Yes, and that "prefabbed house", that is sturdy enough that we can "bury it" under a pile of rock [1] thick enough to provide adequate protection from cosmic radiation, where does that come from? How much mass is that? How is that mass transported to mars? What machines and tools are required to assemble it there, and how much mass are those? How is the energy for these tools provided? [1]: Just to be clear what a pile we are talking about here: If we used the water-shield method, it would require 5m of water for a 50% reduction in radiation intensity.