Lava Tubes on the Moon Maintain Comfortable Room Temperatures Inside
universetoday.com
universetoday.com
There are other big reasons too, like help being only days away instead of months away in the event of a catastrophe.
Once we figure out how to do a space settlement on the moon, then we could try Mars. Mars is likely a better long term home for humans but it's about 60X as far away in terms of travel time.
Just because mining isn’t popular in the media, it doesn't mean its clean. The amount of pollution and destruction it causes is unimaginable.
Let alone the dependency on non democratic countries for rare resources, which just like oil and gas, are finite.
Space based manufacturing will be a thing. Raw material import/export is prohibited by the laws of physics.
That is preferred. Why manufacture anything here when you can have better processes outside. I.e.: welding works better outside earth's atmosphere through cold welding. Pretty sure there may be other manufacturing processes that can be done better out there with the aid of bots and little human interaction.
> the enormous energy required to escape the gravity well.
Enormous based on what we know so far. I am sure if we put effort we'd reach far. I imagine people 100-200 years ago thought building massive metal based ships that carry thousands of people and are the size of a building block required enormous energy. Yet we do it for fun these days.
All we can do is figure out economically viable ways of producing and using that energy.
Enormous ships use enormous amounts of energy. Our ability to harness sufficient energy is what makes those ships possible.
Earth is a treasure of life and biology. Space is filled with endless resources but no known life.
The equation is very, very simple. Protect the life on Earth at all costs and reduce interference in natural evolution. Migrate off-world to barren wastes and mine them.
Every feasible activity that can be done off world, should be.
Use those space resources to build self-sufficient extra-terra systems and eventually migrate all modern / advanced tech off of earth, and remove all traces of our existence there so that new intelligence can take root.
Leave behind only humans who live simply.
There will eventually be a threat to Earth's biosphere that we simply lack the technology to divert, avoid, or remediate. Pretending that this isn't true eventually results in human extinction.
Rogue black holes, gamma ray bursts, or even the very fundamental constants of known physics shifting to a more stable form and that new rule propagating at light speed imperceptibly — and countless, countless other possible dangers. We are no where near the technological level to deal with these, as we cannot even deal with simpler world-ending events (meteor strikes, desertification, proper stewardship of emerging AI, nuclear war).
In addition to all the other reasons one can muster, our advancement in technology can easily be motivated and justified by the objective of Earth preservation and propagation.
It will be interesting to see, however, as we potentially discover other forms of life maybe in places we actually think are barren, how we as a species cope with that. But we are not even remotely at that problem space yet.
Seriously though: I do think a far future option for preserving the Earth is to move at least heavy polluting industries off world. All technology is not going to happen but we could put Shenzhen on the moon. I could see the moon being Earth's industrial park.
On the front of moving industry off world, it does not need to be far future. In fact, we really should have gotten on this years ago already.
We are behind schedule.
Our aversion to nuclear tech has set humanity back decades. Chemical rockets are not sustainable. Nuclear fusion rockets would be, but fear of nuclear fission made society largely afraid of all things nuclear & reliant on oil based energy gen, and the advent of dirt cheap solar allows us to have more time being afraid & using energy sources that constrain us to Earth’s surface.
Use of nuclear energy comes with it a more educated world populace wrt nuclear engineering (nuclear physics is more or less completely understood so the adventure here is in engineering and material sciences). With that more educated populace comes miniaturization of nuclear reactors, materials that can handle radiation better, perhaps even materials that can generate charge when struck by radiation such that most energy is captured in a usable form instead of generating unstable isotopes (think: like solar panels but for alpha / beta / gamma radiation). It also means more people with the background to make fusion a reality.
With fusion reactors comes fusion rockets. Contained plasma has a cool feature of being useful as a clean, high-energy matter stream that can be ejected (and imparting force) while simultaneously generating energy, all while potentially requiring orders of magnitude less reactant mass. This would completely change our relationship with space.
Now it's just sad.
No, space won't save us. We have to stabilize the planet first.
Neither of the celestial bodies have mediums for growing food in so that either has to be manufactured or carted over. Either way it’s a huge challenge to overcome.
Getting to Mars is not that bad... sometimes. Other times you're really going to want to wait until sometimes comes back.
The huge temp swings, now that's actually a real problem.
Just imagine you need complec heart surgery - you can make it from the moon to a hospital in 3 days. On mars, you are probably dead
Now, you do need 50,000 km of Kevlar, and that sounds like a lot until I tell you that there are 1.2 million km of submarine cable right now. We got this one.
If my calculations are right, 50,000km of 5cm kevlar cable (which probably isn't nearly thick enough near the top) would weigh over 500,000 metric tons. Which would take around 25,000 Falcon Heavy launches to get to the moon
I hope it can be manufactured on the moon or on an asteroid or something.
Starship can apparently take 100t to the moon which would be 5000 launches. Elon math has cost per launch eventually reaching $2m which would mean $10b to get the cables to the moon. If terminally optimistic Elon math is roughly correct that puts the project into merely unlikely territory rather than impossible.
The SpaceX website says “100+ t” to LEO. So 100t is a lower bound? Who knows? [1]
However: “Starship can land 100 tons on the lunar surface," said Aarti Matthews, Starship Human Landing System program manager for SpaceX.” [2]
Aarti may mean “with refueling in LEO” so that would require additional launches without an established orbital refueling station. So to fix my math would require knowing the cost of tanker launches which I’m not going to attempt to do.
1. https://www.spacex.com/vehicles/starship/ 2. https://arstechnica.com/science/2022/05/spacex-engineer-says...
Imagine you are one of the first 100 people on the moon, how many doctors will they have, 1? 2? How much medical equipment will they have, how large does the base get before they ha e an x-ray? Will they even have a dentist?
Are they going to have an MRI to find out why you have persitent pain in the chest? Are they even going to have a surgical theater?
They definately won't be able to do a liver transplant. But they might not even be able to do something basic like fix a broken jaw and a root canal.
It'll be really popular for maybe 6 months, 1 year maximum. After that, everyone will lose interest.
We've already seen this before with the Moon: when Apollo 11 landed on the Moon, everyone in America (and probably all around the world) watched in on TV. With subsequent missions, no one cared, except when there was a big problem with Apollo 13 and the astronauts' lives were at stake.
...and every day parents around the world are making more new fans than ever.
- Lonely Island, Space Olympics
1. Lava tubes will be a cheap form of initial habitable space. Additionally, the Moon is geologically stable;
2. Gravity is too low in both places so you'll probably have to still live in spin gravity;
3. Mars has an atmosphere but it's basically a vacuum. It's just enough to cover all your stuff in dust;
4. Mars is poisonous. The surface is covered in many toxic substances (eg perchlorates);
5. People have a vision of living on the surface of Mars. That'll basically never happen. Radiation is still a problem. Living underground just makes way more sense. And any above ground structure (eg domes) can just as easily be built on the Moon;
6. Distance from Earth is a significant downside to Mars and a significant advantage for the Moon. You can still maintain real-time communication with Earth. And supplies are days not months away.
Mars really only has 2 advantages:
1. Day length. Mars day is almost Earth normal. The Moon is tidally locked so its day is ~28 Earth days long; and
2. Day-night temperature differential on the surface. It's really large on the Moon.
Why this matters is that even though you'd be living underground you still need power and solar power is really the best option. On the Moon this means your best options are the poles.
The standard retort is "terraforming". People who say this don't seem to comprehend what a massive undertaking this is. Example: the Earth loses (IIRC) ~1 million tons of atmosphere every year due to Jeans Escape Energy. That doesn't matter on Earth because the atmosphere is so much more massive.
So at actual atmosphere on Mars would have to be so large such that a similar loss would be insigifnicant.
3. Available water, required for any human/plant/animal life
4. 2.3 times the gravity of the moon
5. CO2 in atmosphere could be converted to O2 for breathing or methane for rocket fuel
Mars had much less harsh living conditions than the moon and having water and CO2 around makes living off the land, at least partially, a lot easier than on the moon. The delta-v to get to the moon vs. Mars isn't much different. Getting out of Earth's gravity well is the hard part.
4* Is that enough? We don't know, we've yet to do any centrifuge habitat experiments with small mammals
5* oxygen is so common, CO2 has the advantage of being gasseous, but silicates, aluminum and iron ores are the rocks you can't throw a rock without hitting and has the advantage that you only need to process a millionth the volume to get an equivalent number of moles to martian CO2.
Discovery - Other than spots where part of a lava tube's roof has already collapsed, how quick & cheap is it to discover and map the lava tubes under some non-trivial part of the lunar surface?
Scale - Let's say there's a lovely lava tube, X meters in diameter and Y meters below the surface, in a location where we'd like to build a moonbase. For a give size of moonbase, there will be fairly narrow ranges of X and Y values where the lava tube is actually suitable for housing the moonbase.
Cut & Fill Competition - Lava tubes aren't magical. If an area on the moon has deep, stable "soil" (vs. near-surface bedrock) containing ~few larger pieces of rock, then "dig a trench, install tubular habitat, fill trench back in" may give a far lower cost and/or higher predictability than "starting looking for the perfect lava tube...".
Stability - If you're not familiar with the things that often go wrong when humans start digging and building structures, Practical Engineering ( https://www.youtube.com/channel/UCMOqf8ab-42UUQIdVoKwjlQ ) is a pretty good intro. Note that we have a lot of experience with and data on how to do such things on the Earth. On the moon...not so much. Some very painful and expensive lessons seem inevitable.
https://www.nbcnews.com/mach/science/gigantic-lava-tube-coul...
At some point, the ideas start to sound like "wouldn't it be great to build a thousand-square-mile tropical island, in this spot where the ocean is only 3 miles deep?" Sure, if you know somebody who'll give you ~5,000 cubic miles of good rock, delivers cheap, and there's no "asteroid impact" in the fine print.
Check out the video on this page for a ton of details: https://www.kiss.caltech.edu/lectures/2018_Moon_Diver.html
That particular mission concept was not funded, unfortunately, but I'm hopeful that we'll do something like this soon. As others in this thread have said, aside from just being really cool these lava tubes on the moon (and Mars! https://en.wikipedia.org/wiki/Martian_lava_tube) are an interesting candidate for human habitats.
> The researchers used computer modeling to analyze the thermal properties of the rock and lunar dust and to chart the pit’s temperatures over a period of time.
I'm not sure I'd trust a lining applied to a naturally-formed tube wall to retain air. But if we were to build our own tunnels with a lunar TBM¹, where we could control what the tunnel wall is like, yeah, that'd be fine.
What kind of control do you think you'd have that would make the 'artificial' tunnel better?
1. You'd have a flat smooth surface that you could apply a liner to, instead of a surface that undulates and (probably) has fissures.
2. The diameter would also be constant, so that you could design your liner to fit based on known dimensions. Curves would also be of a known radius.
3. Also, our tunnel would go exactly where we want, and not wander around based on some ancient flow pattern. Or form oxbows where it loops back on itself.
4. So far as a structural liner, if you look at some of the tunnels under rivers where there is the danger of water intrusion, to my knowledge none of them have ever used a natural formation. Brunel used a brick structural liner under the Thames, and modern TBMs use interlocking concrete panels with rubber gaskets.
I think you're making a lot of assumptions, and don't have a comprehensive view of how the structure(s) would be designed and built.
With the daily big temperature swings, is this a viable source of power?
Earth is actually undergoing a similar process... IIUC, our planet isn't big enough to generate internal heat, and eventually the core heat should radiate away. I don't know if the time scale for it exceeds lifetime of the sun though.
I swear, every time I learn a new thing about Earth's internal structure it gets weirder and cooler.