hckrnws

His cost numbers for reliable supply from either nuclear are solar are in the $150B per GW range. A reactor like that might serve 1.5M terrestrial customers. The thing is martians use electricity for everything while flatlanders use a variety of energy sources. Also martians use electricity to provide services that are provided by the ecosystem on Earth such as breathable atmosphere, climate control, prevailing oxidization states, etc. His chart says martians use 100x as much water, methane and other primary resources so that can support 150,000 martians which also take 1500 Starship flights at a cost of $150B. Solar has the advantage is that it can be deployed as scalable modules to support the first 1,500 martians as well as the next. However 20 or 30 years in the future those martians need a new power plant. If they were serious about establishing a durable presence on Mars they'd also be reproducing and growing in population.

Eric Drexler gave up on the Gerard K. O'Neill vision because he foresaw the problem of that kind of economy being dependent on the Earth for some high-leverage aspects of technology. A Mars colony has to expect that terrestrial sponsors may give up on the project someday so they have political reasons to develop self-sufficiency. (e.g. it's hard to see how a Mars colony would be profitable to the Earth as a whole) Some radical advanced in manufacturing that allows a small group of people to manufacture everything they need for their survival on a strange world seems necessary.

Sooner or later the martians will need to build their own solar panels, batteries, nuclear reactors, whatever. Today I think it is a profitable research area to look into manufacturing techniques that might let a colony of 15,000 martians be largely self-sufficient in that this research could pay off here on Earth.

Some other stuff martians will need:

- Replacement rubber caskets for airlocks and the kilometres of plumbing. Synthetic rubber seems petrol based; natural rubber trees seem to need a lot of space.

- A source of fabric for clothes and other cloth stuff. Presumably natural fibres like hemp or cotton or plastic fibres. Sheep, I think, will be right out. Mars is vegan.

- An enormous amount of greenhouses (a lot of glass) or grow houses (energy, insulation) for growing the vegan diet. I assume a Martian colony will look something like this: https://earthobservatory.nasa.gov/images/150070/almerias-sea...

I am not that worried that petrol can be replaced for "petrochemical" applications. Somewhere there is going to be a carbon processing system that harvests CO2 from the atmosphere and either feeds it to plants or cracks it into CO + O2 and builds up larger molecules. Between Fisher-Trospch type chemistry, pyrolysis of waste products and other methods, not to mention advanced biotech, quite a bit should be possible. If we're ever going to have carbon neutral chemicals we'll have to figure this out for terrestrial use.

Nice! Would that fit (unmounted/folded) inside a reasonable number of rockets?

Wonder also what’s the plans to process those chemicals to finite products, in quality high enough to leverage auto-production for those facilities (some) spare parts.

It's basically the same stuff the rockets themselves are made of. Large towers with miles of plumbing and corrosion resistant tanks.

I did a lot of analysis for asteroid mining and one of the things I worried about the most was what to do with the volatiles that come out when you start digging into the asteroid (believe it or not some of them have a lot of trapped gas.) In fact you might want to separate the volatiles out first thing but that involves having storage tanks to put them in.

Once you got a metals line running it wouldn't be hard to make storage tanks (they don't need to be very strong) but you don't want to waste valuable volatiles plus the volatiles could even be dangerous.

On Mars it is different. Water is precious but martians are likely to vent waste CO2 to the atmosphere because you are going to get all your carbon from that atmosphere.

Either way you are going to need storage tanks for resource extraction, chemical factories and such and the quick way to get them would probably be taking Starships apart at least until they have steelmaking working.

Starship can land 100 tonnes on the moon if it can use all its fuel on the way down, it doesn't do much better than the Apollo LEM did if it returns to cislunar space. It's a reasonable plan to land a Starship with a bulldozer on the moon, lay it down into a trench and cover it up with regolith to make a habitat.

for a lot of stuff we make from rubber various types of silicone polymers would probably work too.

>Today I think it is a profitable research area to look into manufacturing techniques that might let a colony of 15,000 martians be largely self-sufficient in that this research could pay off here on Earth.

I don't know how they will be able to manufacture CPUs on Mars, I'm guessing 8-bit CPUs will be more possible than modern day CPUs. I think even Motorola 68K will still require advanced manufacturing equipment to transport to manufacture.

I guess with close to 50 years of CPU design knowledge they would be able to design a decent 8-bit CPU with 16-bit address space. Maybe they would use first 512 bytes as a data/code cache to speed up certain calculations (trig functions) (Not a EE, studying Mechanical). Although there is a lot of code available for Z80, 6502, 8080 CPUs.

I think rather than experimenting with fabbing on Mars, you would probably be better off sending an absurd amount of CPUs from Earth. A 300mm wafer weighs 150 grams and can fit 30k Raspberry Pi Nano CPUs on it, 2mm^2 on 40nm.

If you send up a wafer per person, which can be laser cut and placed into more easily constructed electronics locally, you've got hundreds of years to solve the fab problem in a worst case, Earth no longer exists situation.

Besides the hilarious conflation of "mars base" and "lunar base" in the introduction, is there any reason this author is to be listened to for his authority? I have a hard time buying that solar and "energy beaming" are more practical power sources on Mars than nuclear reactors..

Solar because r^2 diminishing returns

It's not conflating, it's comparing, and draws the conclusion that "energy beaming" won't work on Mars. It also correctly discusses the challenges "nukes in space" has from a policy and practical standpoint.

> While the Earth-facing side of the Moon can obtain practically infinite quantities of very cheap power if we beam it up from Earth, which is greatly preferable to attempting to engineer some sort of solar or thermal system which can cope with the Moon’s 28-day day-night cycle, this approach won’t work on Mars.

Handmer sometimes speaks outside his core competencies, but I find his napkin math to be extremely insightful.

You may enjoy his recent interview on Patio11's podcast:

[1] https://www.complexsystemspodcast.com/episodes/solar-economi...

He runs a startup that is working on a methane synthesizer that might find uses on Earth but would be very much in demand on a Mars colony.

+1 on the podcast, it is excellent. I only wished he would have dug deeper on details on what they are building at Terraform.

what is his core of competence ?

He has a PhD in physics from Caltech (general relativity) and then he worked for NASA JPL as a software engineer

He is one of the few (only?) person who when talks publicly about this or that space projects or ideas, tries to include ALL potential costs into big picture, even if they are very rough estimates.

Usually when corporations or officials speak about space, they cherry pick some single issue, or maybe a few but not all of them. E.g. talk about weight but forget about cost, talk about weight and cost but forget about cooling. Or when companies talk about any complex gadgets in space and forget to account for them being space based, thus more complex and expensive. These incomplete PR statements are useless for regular people outside of the industry because we lack a lot of knowledge to fill the gaps.

But reading his posts we can very quickly and reliably get basic understanding why some ideas are dead ends for nearest century despite being hyped, and why others are potentially interesting. Also he references a lot of sources in his posts, which would be hard to find but here they are linked in the relevant articles.

And finally his roasting of the Space Disgrace System is worth it on it's own really :)

This man has 2 small self published books on the topic of mars colonisation. He is obviously a serious expert to listen

> This man has 2 small self published books on the topic of mars colonisation. He is obviously a serious expert to listen

Well, (a) self-publishing is free, and (b) expertise cannot be established by proclamation, it requires evidence. Just as in science.

Earlier, the originator proposed an Earth-to-Moon microwave power supply link, which makes no sense at all for multiple reasons. That proposal suggests a lack of basic engineering knowledge.

I actually don't believe at all the feasibility of mars colonisation and was just ironic. Maybe this person has good credentials but it is not visible from his website

I have no opinion on the matter but I feel it is my duty to point out that having written books in and of itself is no indication of the quality of their work so your stated logic does not follow, unless you dropped an /s

Sorry if it was not clear but I was ironic. I don't think that small published books are good credentials.

It's always hard to tell on the internet! But I had a feeling you might have been... ;-)

On Mars the r^2 scaling just means that solar panels produce ~half as much energy as on Earth. For dust there are electrostatic sweeping grids that automatically remove it.

Realize that nuclear also gets more expensive on Mars, because there are no convenient lakes or rivers for cooling water. Instead you need to build a large radiator or underground pipe grid.

About 43% of the energy. But its also worse than that because Mars has a more eccentric orbit and slightly bigger axial tilt. Seasonal variations in solar energy are thus much larger than on Earth (at perihelion you get around 700W/m2, at aphelion about 500W/m2). Also seasons are longer on Mars and the planet moves more slowly around perihelion, so that it spends more time further from the Sun.

You also get global dust storms enveloping the planet every few years for several weeks at a time. These leave a lot of dust on panels, but they also drastically cut the solar radiation received at the surface.

Solar panels degrade faster on Mars too. You could replace them by sending new ones, but that will add up to a lot of mass. Or you could design panels that degrade more slowly, but that's not a given yet.

Basically solar is not going to scale well on Mars. It might work for a small facility, but not for a city.

If you choose your latitude right (roughly 10-30 degrees North), the variability caused by eccentricity and axial tilt mostly cancels out.

https://images.squarespace-cdn.com/content/v1/61b40f74f9cdfc...

As for dust storms, you need stored energy anyway -- nuclear power goes down too! A big tank of oxygen counts as "stored energy," and so does a big container of desorbed lithium carbonate (CO2 scrubber material).

I expect solar infrastructure for Mars would be done in orbit and beamed down. On earth, they are produced on the ground and putting them in orbit cost way too much.

If the panels are send from Earth to Mars, then dropping them in orbit mean that you don't have to account for their weight for landing... or don't have to land at all. Park in orbit, drop you payload and back to earth for the next delivery.

Casey has an article why beaming energy from space to ground is not worth it, due to many compounding issues. Mars can probably only strike off one issue, about beam density and ramp it up, but has many more unique issues - far away to control and replace, less energy density per area, and other issues with small colony size.

https://caseyhandmer.wordpress.com/2019/08/20/space-based-so...

> I expect solar infrastructure for Mars would be done in orbit and beamed down.

Remember that Mars' atmospheric pressure is a tiny fraction of that on Earth, so the performance difference between a solar panel in orbit, and on the surface, is negligible (until a dust storm starts). So there's no reason to consider putting them in orbit, especially considering the much higher complexity and power losses involved in delivering power to the surface.

The point of doing it in orbit isn't the increased performance, it's the reduced maintenance, and reduced transportation cost.

Every drop of fuel used to land and take-off has to be send to earth orbit first. If you replace that fuel with payload, you're looking at a very different equation.

"the performance difference between a solar panel in orbit, and on the surface, is negligible (until a dust storm starts). So there's no reason to consider putting them in orbit, especially considering the much higher complexity and power losses involved in delivering power to the surface."

I wonder if you could build a space elevator on Mars (third of our gravity = much less demanding on materials) and then simply get the electricity generated by orbital solar panels back to the surface using ye olde cables, immune to dust storms.

> Basically solar is not going to scale well on Mars.

With 500W in every season, no clouds, things compare well to where I live. Should give close to 1000kWh/year, but reliably so.

If you had a city, could you produce them locally then?

Yes, but you then need to have an already developed full supply chain, and for that you need to bootstrap your energy production first hand.

My personal hope is that there might be some untapped resources of hydrocarbons or methane in Mars that could be used to generate energy from local sources.

Local hydrocarbons could help for making materials/chemicals but they wouldn't help for energy. Mars doesn't have free oxygen in the atmosphere so there's nothing to burn them with.

Mars is very cold, so all this waste heat from nuclear reactor can be used to heat spaces, but nuclear reactors needs enriched fuel to work, which is dangerous to transport.

If Petrovskite Solar Cells will work on Mars reliably, they can be produced directly on Mars and used together with sand batteries for stable supply of energy and heat.

Surely most of the waste would be needed for space heating and process heat?

It's all about the weight. Solar panels are light, nuclear reactors are not. Handmer correctly focuses on the metric of tonnes per megawatt.

I only skimmed it but he clearly says that "energy beaming" won't work with Mars.

I also don't think there was any "conflation."

It's a good article, well research but feels amateurish in some parts.

For example, he seems to be confused about energy vs. power, which units to use and what to they mean.

- "For example, if we need a gigawatt of energy (10,000 people at 100 kW each) and space reactors weigh ( https://en.wikipedia.org/wiki/Kilopower ) 150 T/MW, we’ll need to salami 150,000 T of reactors between 1500 Starship flights..."

The example he's drawing on (NASA's Kilopower concept) is a 10-kilowatt sized reactor and it's probably a bad extrapolation to scale from that to the 1-gigawatt scale, linearly.

This is at least a 50-fold overestimate of mass. From nuclear electric propulsion literature [0], the mass budget for space electric power plants at the 15-megawatt scale optimizes to around 3 tons / megawatt. (I couldn't find serious engineering studies at the gigawatt scale).

[0] https://inldigitallibrary.inl.gov/sites/sti/sti/2688772.pdf ("Multi-Megawatt Power System Analysis Report" (2011))

(Mainly, the closed Brayton power systems summarized in table 4, on page 26)

As an aside, post-2000 research like your link really makes me wanna dive into notoriously-crunchy sci-fi RPG & wargame systems and validate/update their construction rules to account for advances in the science. Mostly thinking GURPS: Vehicles and Traveller's Fire, Fusion, and Steel....

https://boardgamegeek.com/rpgitem/49409/fire-fusion-and-stee...

- "For example, if we need a gigawatt of energy (10,000 people at 100 kW each) and space reactors weigh 150 T/MW, we’ll need to salami 150,000 T of reactors between 1500 Starship flights..."

This is not a good estimate because the scaling laws you should be looking at are very strongly sub-linear. It's a major error to take a 10 kW design and flatly multiply it by 100,000x.

This[0] is what mass-optimized, gigawatt-scale space nuclear reactors look like. They don't need 1,500 starships; they would fit inside one—they were designed to fit in one, because they are rocket propulsion engines.

[0] https://en.wikipedia.org/wiki/Project_Rover

([late edit]: Anticipating the strongest criticism: these weren't electricity-generating reactors, true—but those subsystems can be highly miniaturized as well. The power density of gas turbines is incredible. A single Starship has 2 gigawatts of turbopump shaft power, distributed between its 30-something engine fuel pumps).

> This is what mass-optimized, gigawatt-scale space nuclear reactors look like.

A nuclear rocket and a nuclear power plant are vastly different things, for the same reason a jet engine and an oil power plant look quite different.

The reactor itself is a spatially small part of everything - the little doughnut in the middle. https://commons.wikimedia.org/wiki/File:EPR_1_EPR_2_perso.pn...

I'm aware of that. But your commercial power plant example is also far from optimized for the requirements of a space power plant.

((edit): Your jet engine analogy is apt: a turbojet is a highly miniaturized version of the same type of turbine used in gas power plants. It'd be quite a mistake to look at a power plant turbine and analogize from that that jet airplanes are impossible, because, well, just look how huge those turbines are!)

In theory you can build a low capital cost and compact nuclear reactor that operates at high temperature with a closed-cycle gas turbine powerset

https://ntrs.nasa.gov/api/citations/20140016755/downloads/20...

It could be a molten salt reactor or a liquid metal fast breeder reactor or a high temperature gas cooled reactor (carbide fuel in prismatic or pebble form) It could be highly competitive with solar as a carbon free energy source for terrestrial use but it is not a bird in the hand.

(I think the robots in Gundam use a power plant like that which is why Zakus blow up when you hit them)

I imagine the reactor, powerset and all, would be packed up into one Starship load but would have some civil works (cooling system) assembled on site. In another comment I point out Casey is accounting for 1 Starship launch of powerplant for 1 Starship load of colonists so this could scale OK from that point of view.

Presumably they use a closed fuel cycle which is more like

https://www.youtube.com/watch?v=KEfhx5ovuYk

than Sellafield.

- "but it is not a bird in the hand."

Kind of amusing to read this in the context of a "city on Mars" discussion :)

- "Presumably they use a closed fuel cycle which is more like"

I doubt this. Nuclear fuel reprocessing is a very invasive thing—a difficult industrial process that's hard to get working even on Earth, let alone resource-constrained environments like a putative Mars settlement. I doubt metal-fuel reprocessing like what you linked with the EBR changes the equation much.

Reliability and maintenance would be the top drivers here. You'd end up with something like the nuclear submarine solution: tiny, self-contained systems that (in the sub case) are just replaced once every 30 years for refueling. This drives you to choose 90% HEU as your fuel. Beyond what submarines have as their requirements, you're, in addition, critically constrained on mass. That, I think, strongly drives you to unmoderated fast reactors: small, dense cores with lightweight coolants like sodium. From memory, I believe all of the 30+ space reactors that were actually built were HEU fast reactors with Na or NaK coolant. (There's actually droplets of radioactive NaK in Earth orbit right now, according to Wikipedia, because one of them leaked).

(This is not my field of expertise; I just spend a lot of time reading NTRS).

It's hard to say.

HEU cores can go to a high burnup in a fast reactor (and leave very little actinide behind) but the burnup is limited because U235 depletion will drop reactivity. If you are breeding new fuel that reduces the reactivity drop.

Modern FBR cores can get maybe 30% burnup of fertile material without reprocessing. Rather than the low-latency reprocessing cycles that people thought about 1950-1970 martians might not think of reprocessing for 20 years or so.

If they really need to ship 1000+ Starship sized reactors they are going to have a different attitude about reliability (e.g. a 5% failure rate that don't make a mess is no problem)

I could be wrong but I think space colonists would be fanatical about a circular economy. If they had 1.5 million people on the ground they could not count on getting a new reactor for every citizen every 25 years. I've done some modelling of an asteroid colony where I'd expect people to not waste a wisp of carbon dioxide, for instance, martians on the other hand would have no problem venting it to the atmosphere because they will source it from the atmosphere.

An in-space power plant isn't the proposal, though. It would be on Mars, and have similar requirements for containment, cooling, maintenance, etc. We are unlikely to want to spew radioactive hydrogen all over the landscape.

It's a fascinating topic, isn't it?

The hydrogen exhaust in nuclear thermal rockets isn't actually radioactive (well, in practice it was, because the rockets they actually built had a tendency to fall apart and eject bits of their nuclear fuel in the exhaust, but on paper that shouldn't happen). But the power-plant versions are closed gas loops anyway—you're driving the hydrogen or helium through a turbine, it's a sealed system.

I don't think you'd choose to build any serious containment building on Mars. The baseline risk of death on Mars is extremely high; nuclear accident risks don't appreciably move the needle. My understanding is what you'd actually do is put a biological shield—maybe a pile of Martian rock—on the line-of-sight between the reactor and the astronaut base, and, simply, never walk that way.

Cooling is substantially easier on Mars than in space, since there's an atmosphere that functions as a heat sink. The space version (i.e., in the nuclear electric propulsion context) has a more difficult challenge, with radiation as the sole heat dissipation mechanism.

You're right that a space reactor would have to be designed for zero maintenance, else it'd be a non-starter.

Westinghouse recently announced a mini-nuclear reactor capable of powering several hundred homes (https://info.westinghousenuclear.com/news/first-canadian-evi...). The reactor itself is the size of small apartment and would fit aboard a spaceship (the now defunct Space Shuttle) and is light enough that a large rocket (like the Saturn) could carry it into space. The reactor plant would be constructed around the reactor at its final destination (in this particular case, Saskatchewan Canada, but for purposes of this discussion, Mars).

As a side benefit of the design, it uses the heat of the reactor to provide heating, which a Mars colony would need a lot of.

The guy missed a third option for powering Mars vehicles: compressed "air" engines. On Mars the "air" is CO2, but the actual gas is not that important. On Earth compressed air vehicles were tried, and they mostly failed, but that's because there are other more efficient alternatives, like the plain old gasoline powered cars. But on Mars, the simplicity of spinning a turbine with CO2 coming from a pressurized tank is hard to beat. You would then let the CO2 vent in the atmosphere.

I would love someone with more knowledge to fully explore what a similar sized space station could achieve compared to the arduous task of going down martian gravity well that has half the solar energy and on top of that a night cycle which halves your solar output again.

Any viable colonisation strategy would need to overcome the yet unknown downsides of lunar/martian dust and many other potential threats. What you get back is a rock like earth but without any of the useful infrastructure. I just dont see any scenario where a mars base would outperform a space station above mars/earth/moon/lagrange point with the ability to recover asteroids of a few metric tons. Even microgravity issues could be solved by making a massive rotating habitat that could serve hundreds of people easier than you could keep 10 people alive on mars.

> I would love someone with more knowledge to fully explore what a similar sized space station could achieve compared to the arduous task of going down martian gravity well that has half the solar energy and on top of that a night cycle which halves your solar output again.

Issues:

First, the solar energy at the surface is much the same as it is in orbit, because of Mars' very thin atmosphere -- unless a dust storm kicks in. This means there's no justification to use orbital solar with the attendant high capital costs and conversion losses.

Second, being able to live below the surface in any of the existing lava tubes as protection against high surface radiation levels and wide temperature extremes, thus eliminating all the complexities of an orbital presence, makes the orbital option a non-starter.

Third, an orbital presence would require generating artificial gravity to prevent known and serious health issues, less true for a surface colony (Mars' surface gravity is 38% that of Earth).

Fourth, a carefully chosen lava tube site would have much better control over environmental temperatures than a surface or orbital colony. Remember that Mars surface temperatures regularly drop to -100F overnight. Temperature extremes would also be an issue in a lava tube, but with less severity if the site were carefully chosen.

I think a Mars colonization project at scale will choose a surface colony over an orbital presence on multiple grounds.

> I just dont see any scenario where a mars base would outperform a space station above mars/earth/moon/lagrange point with the ability to recover asteroids of a few metric tons.

If the mission is to collect or mine asteroids, that would change everything. All the above assumes some other purpose -- for example, Mars surface mining.

>If the mission is to collect or mine asteroids, that would change everything. All the above assumes some other purpose -- for example, Mars surface mining.

If we had the ability to mine mars, that would change everything. But this is precisely why I'm suggesting that a station in space might be superiour to any mars base. A station doesn't have to be near mars, lots of locations, asteroids and points of interest are closer to us than the surface of mars. Even going to mars will be easier if you have the station first.

>there's no justification to use orbital solar with the attendant high capital costs and conversion losses

Are you talking about orbital solar for a non-existent mars base? A space station can have 100% uptime of their solars cells without the problems dust brings. Mars is the one with conversion losses if they need to store any power for any length of time.

>being able to live below the surface in any of the existing lava tubes as protection

Radiation protection is just a cost figure for a station. Converting lava tubes into something we could use seems like a herculean effort without even knowing any safety aspects. You're just limiting your own space on a dead planet.

>artificial gravity

We could spin the habitat. It would be easier than testing lava tube methods of engineering.

>Remember that Mars surface temperatures regularly drop to -100F overnight. Temperature extremes would also be an issue in a lava tube, but with less severity if the site were carefully chosen.

Stations win again as we've already solved this.

The advantage of being on Mars is that as your population expands you mostly need to just dig more tunnels for them to live in. With a space station you have to build more space stations or somehow add on to your existing one, which is very difficult with artificial gravity setups. The explosive failure modes of a space station are less of a concern on an underground Mars colony as well.

But this of course raises the question as to why you would do either instead of staying on Earth. Elon Musk talks a lot about a multi-planetary species, but it's extremely unclear how long it would take for a Mars colony to become self sufficient. And anything you can do underground on Mars you can do underground on Earth but with fewer catastrophic failure cases. The only threats a Mars colony protects against are a dinosaur killing asteroid strike and a completely runaway greenhouse effect turning Earth into a second Venus. Even worse, if Elon were serious about the Mars colony he should have multiple fully self-sufficient test colonies on Earth vetting out the technologies now, but if he had that it negates the need for the Mars colonies.

underground tunnels on earth the day after an asteroid strike would still be more hospitable than tunnels on mars

mars is an insurance policy for essentially a 100% extinction event (save maybe a bio-weapon targeted against humanity). Anything much less than 100% and I imagine a pocket of humanity would survive. That would be like the entire surface of the planet getting liquefied or a gamma ray burst directly hitting Earth.

A gamma ray burst that sterilized the Earth would also wipe out Mars.

In addition the surface of Mars has lots of radiation which would require you to live under some sort of shielding or in a cave.

>The average radiation level on Mars is 24–30 rads (240–300 mSv) per year, which is 40–50 times higher than Earth's.

Everything on Mars is designed to kill you. I don’t understand the appeal either except for ultra rich on earth that are looking for a new exclusive neighborhood to move into, away from the serfs funding it.

Earth is boring, Mars is exciting. Why solve the immediately available, mundane and sometimes hard issues we have on earth, rather than to entertain one's intellect in a purely theoretic grapple with the most interesting few of the distant problems we'd have on Mars?

> Why solve the immediately available, mundane and sometimes hard issues we have on earth, rather than to entertain one's intellect in a purely theoretic grapple with the most interesting few of the distant problems we'd have on Mars?

Because Earth is boring, Mars is exciting. More pointedly: on Earth you’re fixing problems amidst a tightly-regulated status quo. On Mars you’re pioneering. We have way more people in the computer sciences than stewardship roles because human nature prefers to explore.

> Earth is boring, Mars is exciting. Why solve the immediately available, mundane and sometimes hard issues we have on earth

Why must they be mutually exclusive?

The space race that started seven decades ago brought immense benefits to humanity as a whole. Any progress made in the pursuit of colonizing Mars would undoubtedly have positive repercussions for us Earthlings.

>10,000 people at 100 kW each... 150,000 T of reactors ... 1500 Starship flights...

It would seem much more practical, given the way AI and robotics are going, to send a bunch of robots down there to build the Mars base. Then subsequently humans could go visit to avoid an asteroid or take selfies or whatever.

Earth solar cells are thick and heavy mostly because of the protective glass, frames, etc.

The actual silicon is under a millimeter thick, and presumably could be made even thinner.

On Mars, with a super thin atmosphere, there may be no need to protect the cells. Just laying plain cells on the ground might prove cheapest. Sure, they'd be super fragile (imagine potato chips the size of a person and how hard they would be to lay flat on the ground without breaking) and you'd probably have to come up with special techniques to lay them whilst breaking as few as possible.

Wiring is probably the next heaviest component. But with no atmosphere, there is no need for wires to be waterproof or have insulation. Wires could be bare aluminium.

It's probably the martian dust and not the thickness of the atmosphere that creates the need for protection.

absolutely need dust protection on Mars, more than on earth

wind speeds are generally lower, but the dust is thermostatically charged, tends to stick to everything, and is incredibly abrasive — wires would also need to be insulated from Mars dust because it's conductive

it's a very hostile environment for solar, dramatic temperature changes are also a factor

mars dust is conductive? Thats news to me.

it's incredibly dry so not hugely conductive, but any moisture will cause perchlorates within it to dissociate into ions

I wouldn't want to bury a bunch of unshielded wire in it, especially if the wires ever get hot (which can produce moisture given the presence of specific minerals)

News to me as well, but it makes sense at least on the surface. Mars is red because it's covered in rusty iron.

There are folding camping solar panels that are designed to balance portability with reasonable durability.

~200MWt reactors are common in large nuclear submarines and weight about 2000 tons, not sure how much of that (if any) is shielding, but the figures for reactor weight sound high. I’d imagine for joules/kg nuclear would be hard to beat.

One thing I never understand with these terraforming startups is: instead of terraforming Mars, isn't it much more economically valuable to terraform chunks of Earth?

At the end all of this boils down to economics, and instead of spending trillions to terafform Mars, you can buy large swathes of unproductive land on Earth and try to develop that...

The author of this blog is also very into terraforming Earth! https://caseyhandmer.wordpress.com/2024/10/26/we-can-terrafo...

It's nothing to do with economics. Was landing people on the moon economics?

Why climb a mountain?

There is a difference between climbing a mountain and living on top of a mountain. Going to Mars and exploring it is a good goal. Colonizing Mars is a bad idea because it is so hard.

> Was landing people on the moon economics?

No it was an investment. Military and civil research (in so many fields), as well as propaganda (to USSR, US and the world). It was the cold war.

See also: https://en.wikipedia.org/wiki/National_Aeronautics_and_Space...

> Why climb a mountain?

Sports, hobby, in some cases I am sure also inferiority complex.

Neither were done by companies though, so the question still holds, when there appear to be more viable options.

I am not going to judge what makes economic sense, but these questions really don't seem related.

I'm not sure there's much of an economic case for terraforming Mars so much as it seeming kind of cool to be multiplanetary. I'm not sure what the startups are selling.

That said I think I'd prefer they kept it more as national park / site of special scientific interest rather than a construction site.

It looks great, I hope Musk moves there soon.

Why oh why do such flights of fancy focus on heavy bodies when the high-atmosphere clouds of Venus are comparatively so much more inviting. It's all dreams with our current techno-industrial trajectory, but I find the venus cloud cities story more appealing somehow.

> [ ... ] The second reveals that beaming power to the lunar base region with microwaves from Earth is by far the cheapest, most flexible option – for operations on the Earth facing side of the Moon.

Sorry, this fails several tests of common sense. Compare the alternatives:

   * A suitably large solar array near the Moon's north or south pole, with DC transmission lines to the point of use, able to provide continuous power during all lunar phases.

   * A solar array on Earth, then a microwave converter, then a phased-array beam of microwaves to the moon, then an equal-sized phased-array microwave receiver on the moon, then a converter from microwaves to DC, finally a lunar transmission line of some length to (a) avoid the area immediately beneath the microwave high-flux area and (b) convey the power to the point of use.

Let me re-emphasize this one line: "... beaming power to the lunar base region with microwaves from Earth is by far the cheapest, most flexible option ..."

Well, no. Not really. Not remotely. Even geostationary microwave power stations have multiple-conversion and beam-width power loss issues, and that's a small fraction of the Earth - Moon distance.

You’re ignoring the mass-transmission losses of moving heavy panels to the Moon. Concluding the author’s back-of-the-envelope math is a “non-starter” with zero numbers, just hand waiving, is heavy with hubris.

> You’re ignoring the mass-transmission losses of moving heavy panels to the Moon.

I passed on that because both options require a lot of mass transfer -- either solar panels or microwave antennas.

?

> A growing Mars base has a prodigious need for power.

Has it?

Or will it?

Or might it?