Why colonize Mars and not the Moon?

[mfb]

You have the Budget, Will and Technology to build a bunker and self-contained slime-farm on Mars, yet you can't solve the simplest social problem on Earth:
Exponential Human Population Growth.

There is no exponential population growth in industrialized countries. A Mars or Moon colony would be the most extreme example of an industrialized "country".

This pointless distraction by Elon Musk is grotesquely offensive. We have such a beautiful Planet, and he is happy to entertain thoughts of of a forlorn existence in a sad dead wasteland. Instead he should devote all his time and effort to the improvement of humanity and the preservation of our planet. Travel to Mars would represent the ultimate failure of humanity.

Musk could start producing solar cells, batteries and electric cars for a better environment on Earth?

He is doing that already.

Was going out of Africa the ultimate failure of humanity as well?

Mars is not really terraformable. Too small and too low gravity means you can't keep a dense enough atmosphere without constantly re-supplying it.

Re-supply would be a potential issue millions of years into the future, probably solved with technology we cannot even imagine today. We could create an artificial magnetic field with (nearly) today's technology. If we manage to make a Mars colony that survives for a million years I can't imagine this to be an issue. Don't worry about atmospheric losses.

 

[Gardenman]

I haven't read all fifteen pages of posts, so this may have been addressed, but if not, I'm giving it a shot here. I think a lot of people assume terra-forming a planet will be more difficult than it may ultimately prove to be. There are bacteria that thrive here on Earth in nearly every condition imaginable. The right mix of bacteria inserted into a currently uninhabitable planet could transform it fairly quickly. In ideal conditions bacteria can spread quickly. Once the transformation starts different bacterial cultures could be inserted to refine the process until we eventually ended up with an Earth-like planet with a stable atmosphere. Finding the right bacteria that could survive in Mars as it exists now and that excrete what we want Mars to become is something of a challenge, but we know what the surface of Mars is like and we could simulate that in a lab to try and find a suitable mix of bacteria. I suspect the bacterial soup would need to be adjusted throughout the process as the conditions on the planet changed, but a thriving colony of bacteria on Mars churning out what we want Mars to become could transform the planet fairly quickly.

I strongly suspect we could transform Mars into a livable planet in a matter of a few decades if we got the bacterial cocktails just right. We could see a planet with a breathable atmosphere, oceans, storms, and a livable surface created at a relatively low cost within a relatively short window of time. The use of unmanned drones to seed the planet with the bacterial soup is possible and could speed up the process. The lack of water on the surface is a challenge for now, but I suspect it could be overcome.

If it's true that Mars had seas and oceans in the past, along with rainfall, then there are likely caves and caverns on Mars just as there are caves and caverns on Earth. If there's liquid water left on Mars, it would most likely be found in a deep cavern. If you could find a deep cavern or multiple caves/caverns with pools of liquid water, those would be good places to seed the initial bacteria. Bacteria and primitive life are the things that made Earth into the Earth we know. Rather than wait for them to evolve naturally on Mars, we could insert specific lifeforms to shape the planet to suit our needs. I don't think it would be too complicated or expensive and could be accomplished in a relatively short timeline.

 

[Corum10]

I haven't read all fifteen pages of posts, so this may have been addressed, but if not, I'm giving it a shot here. I think a lot of people assume terra-forming a planet will be more difficult than it may ultimately prove to be. There are bacteria that thrive here on Earth in nearly every condition imaginable. The right mix of bacteria inserted into a currently uninhabitable planet could transform it fairly quickly. In ideal conditions bacteria can spread quickly. Once the transformation starts different bacterial cultures could be inserted to refine the process until we eventually ended up with an Earth-like planet with a stable atmosphere. Finding the right bacteria that could survive in Mars as it exists now and that excrete what we want Mars to become is something of a challenge, but we know what the surface of Mars is like and we could simulate that in a lab to try and find a suitable mix of bacteria. I suspect the bacterial soup would need to be adjusted throughout the process as the conditions on the planet changed, but a thriving colony of bacteria on Mars churning out what we want Mars to become could transform the planet fairly quickly.

I strongly suspect we could transform Mars into a livable planet in a matter of a few decades if we got the bacterial cocktails just right. We could see a planet with a breathable atmosphere, oceans, storms, and a livable surface created at a relatively low cost within a relatively short window of time. The use of unmanned drones to seed the planet with the bacterial soup is possible and could speed up the process. The lack of water on the surface is a challenge for now, but I suspect it could be overcome.

If it's true that Mars had seas and oceans in the past, along with rainfall, then there are likely caves and caverns on Mars just as there are caves and caverns on Earth. If there's liquid water left on Mars, it would most likely be found in a deep cavern. If you could find a deep cavern or multiple caves/caverns with pools of liquid water, those would be good places to seed the initial bacteria. Bacteria and primitive life are the things that made Earth into the Earth we know. Rather than wait for them to evolve naturally on Mars, we could insert specific lifeforms to shape the planet to suit our needs. I don't think it would be too complicated or expensive and could be accomplished in a relatively short timeline.

I believe the biggest problem with the thought of Terra Forming is the lack of a viable atmosphere. It as been well stated that the water vapours of Mars have dispersed from the surface into space. How it could be possible to reverse that problem prior to the establishment of a bacteria solution is beyond me. It is a cart before the horse scenario. Many, when discussing Terra forming fail to perceive the immense volume of atmosphere we are talking about and an atmosphere that varies between just above 0C to minus 165?? or so. In addition, the many complicated steps in the Terra forming of Earth itself took place over millions of years. To think we could speed that up and compress it into a couple of decades is just wishful thinking.

 

[mfb]

Bacteria cannot revert losses to space, of course, but they could produce oxygen out of CO2 from the atmosphere (and ice caps, once sublimated) or water.

The sunlight Mars receives is more than sufficient to produce an oxygen-rich atmosphere within years, as calculated earlier in a different thread. We would have to find a way to cover the surface with algae or bacteria, however, and it is unclear how to do that.
A few decades don't look completely impossible.

 

[Corum10]

Bacteria cannot revert losses to space, of course, but they could produce oxygen out of CO2 from the atmosphere (and ice caps, once sublimated) or water.

The sunlight Mars receives is more than sufficient to produce an oxygen-rich atmosphere within years, as calculated earlier in a different thread. We would have to find a way to cover the surface with algae or bacteria, however, and it is unclear how to do that.
A few decades don't look completely impossible.

Agreed, however there is still the somewhat substantial problem of having no magnetosphere ergo no ionosphere. Don't get me wrong I am all for trying and spend much time trying to evaluate the various methods, but fear that people do not fully realize the need from every aspect for a magnetic field around a possible new home, which Mars will never have due to a lack of an molten core.

 

[mfb]

Agreed, however there is still the somewhat substantial problem of having no magnetosphere ergo no ionosphere.

It is not a problem, see post #301 for example.

 

[russ_watters]

Taking the most pessimistic estimate that takes cost overruns into account, and applying cost overruns to it again, sounds a bit pessimistic.But that is exactly what is done as part of spaceflight budgets.

I'm sorry, but I'm just not buying it. Even if what you say is true - that attempts were made to be extra pessimistic at 500 billion - that still doesn't mean it is pessimistic enough. No policy planner would try to make a realistic estimate and then multiply it arbitrarily by a factor of 10, even if that is what it needs. Cost estimators are handcuffed by the limitations of their job: They have to be "reasonable".

Cost estimators base their estimates on the scope of work in front of them and then add safety factors (20%? 30%? 50%?) for common escalations and missed scope issues. These types of issues are normal, rational and at least somewhat predictable.

But the what actually plays the biggest role in determining the cost of a mission to Mars is not reasonable. There is no "whim of Congress" factor that can be applied to a cost estimate. No "I thought this piece of technology would be easy to invent but it turns out it isn't so now we have to re-design the entire project" factor. No "Russia said they'd contribute but balked" factor. No "the first pre-supply mission crashed so now we have a 3-year setback to produce a new one" factor. These factors are inherently unpredictable and unreasonable to include in a cost estimate. But they are real. And in particular, the bigger the project the more likely the "Whim of Congress" factor is to be the one to do-in a project.

Space Station Freedom's demise was in large part due to the "Whim of Congress" factor. Congress demanded repeated re-designs ostensibly to cut costs, but the re-designs and delays themselves added to the costs. A complicated series of problems following that led to the cancellation of it and conversion to the ISS. No cost estimator in 1980 could possibly have had that captured in their budget.

 

[Al_]

Well potentially Mars would be terraformed, and it would be nice as a back-up plan, or as serving the expansion dream of humanity in space. But it would be a lot better investing that money on a class-M planet.
The only one around here, fortunately or unfortunately is earth! With all that money we could have made Earth a paradise!

Do you really think so? How many have tried and failed. How much effort, over millennia, has gone to create paradises or utopias.
There are really deep fundamental driver in human and natural processes that mess up such plans. No everyone wants the same end result. Are science people supposed to solve politics?
Come on, allow some techies the chance to escape the madness.

 

[Al_]

Deimos has a day/night cycle of 30 hours, that doesn't sound healthy.

In experiments where people were isolated from all day/night cycles and clocks in a cave, they naturally adopted a 30 hour cycle. People here on Earth have all sorts of odd sleep patterns, with known marginal health problems. 30 hours is far from the worst pattern we know of. As long as you are not tired, stay healthy and get enough sleep, does it matter?

 

[mfb]

@russ_watters: It is an estimate of the total costs, not for congress, but for a book ("The Scientific Exploration of Mars.").

ESA and Russia made a plan in 2002 and estimated that it would cost $20 billions (Reference).

Mars Society Germany suggested another mission profile, mainly based on existing rockets, with overall costs of 10-15 billion Euros (Reference).

SpaceX estimates $10 billion for development of ITS and something like a billion for a first mission (much less for subsequent missions).

And so on. Most estimates are somewhere between 10 and 50 billion dollars. And all those people making the estimates take into account that things can go wrong. They all know the history of cost estimates for previous programs much better than we do.

You picked the massive outlier, which is questionable on its own, and then you claim you know it better than the book author and go even further away from all other estimates.

 

[Al_]

This thread is not about a first mission. It is about a possible global, large-scale effort to establish a permanent and eventually self-sufficient colony.

Deimos colony could be huge!
In "Mining the Sky" by John Lewis, he reminds us that in the negligible g of an asteroid (or Deimos) you don't confine yourself to the surface of a planet. You inhabit the volume. If one person requires say, a luxury apartment size dwelling of 300 metres squared, by 3m high, round up to 1000 cubic, and the same for services such as food production. 2000m3 per person. Then some of that needs to rotate for gravity, so add maybe 3000m3 spinning space. 5000m3 per person. Very generous.
Diemos is roughly 1000000000000m3.
So roughly 200 million people. That's not a first mission.

Of course, where do the resources come from? Well, quite possibly Deimos has enough for a few thousand people. But for a bigger colony, in micro g, the most economic site for a colony is at a crossroads where all the resources will be transported by. And that will be a crossroads on the Interplanetary Superhighway. http://www2.esm.vt.edu/~sdross/superhighway/description.html
Deimos might be on such a crossroads one day? If so, why not buy it for a few glass beads?

 

[russ_watters]

ESA and Russia made a plan in 2002 and estimated that it would cost $20 billions (Reference).

C'mon, mfb; that is just plain garbage. It says in the link that the Russia made the plan, to include the ESA, but the ESA didn't buy it. 2/3 of the article is about how unserious it is.

SpaceX estimates $10 billion...
And so on. Most estimates are somewhere between 10 and 50 billion dollars...

I'm having a hard time believing you are taking this issue seriously, mfb. The ISS cost that much just to build it, so these numbers aren't even good as fantasies. They are lower and shake your head numbers. They aren't even in the right order of magnitude. Elon Musk is allowed to be P.T. Barnum because that is part of his schtick/aura that gets investors to invest in crazy projects that sometimes work out, but we can be better than that. I can't possibly fathom how you could believe a manned Mars mission could be done for $10-$50B.

More to the point, this "most estimates" you cite really aren't. Those are the outliers. All I did was take an estimate I thought you thought was realistic (and for the record, I think it is too, just without the "whim of Congress" factor) and double it.

It is an estimate of the total costs, not for congress, but for a book ("The Scientific Exploration of Mars."). ...and then you claim you know it better than the book author and go even further away from all other estimates.

No, I'm not saying I know better than the book author. What I'm saying is that I'm not constrained by the limitations of the book author. It's also worth pointing out that everyone has biases and motives here; almost everyone putting out a book or a low estimate has a bias toward a low-end estimate. My bias is the opposite: I'm biased against wasting money.

 

[Al_]

Ask not what the colony will cost. Ask what the colony can sell to Earth!

 

[Al_]

... and then ask what it will cost

 

[rootone]

Ask what the colony can sell to Earth!

That's really the central question.
Even if a colony was to provide stuff to Earth for FREE, the cost of maintaining the colony and transporting the stuff would be high.
Almost certainly much higher that producing the same stuff on Earth, unless it's something unique that can't be done on Earth.
A small manned base could provide useful scientific research, but no need of a fully self sufficient colony for that.
The argument for establishing a second home planet for humans is logical, but I think is politically unsellable except in a doomsday scenario.
Most people would I think probably prefer to see environmental degradation on Earth curtailed first,
or even uninhabitable regions on Earth made habitable, (at a fraction of the cost per inhabitant).

 

[mfb]

A mission to Mars would be smaller than the ISS, not packed with all sorts of different expensive microgravity experiments, and we learned a lot since the ISS started. And the mission wouldn't use the extremely expensive Space Shuttle. All those estimates are made by people who know the costs of the ISS program. Claiming (especially without evidence) that they didn't learn anything from it is an insult to the people making those estimates.

Elon Musk is allowed to be P.T. Barnum because that is part of his schtick/aura that gets investors to invest in crazy projects that sometimes work out

Sometimes? Look at his track record.

What I'm saying is that I'm not constrained by the limitations of the book author.

What exactly prevents a book author from making realistic estimates?

 

[wud-wurks]

Interplanetary travel is a useful technological goal that is likely to have multiple spin offs into regular lives on Earth. Colonising Mars is for the birds in my mind, putting a vehicle on the surface to explore it I applaud , but the logistics of supporting a colony on the surface is balmy.

I sense a running away from the problems on this planet by those who advocate such a dream, would it not be better to incrementally explore our nearest planets as we have been doing and apply our not inconsiderable skills to solving some of the issues on this one?

 

[wud-wurks]

I support the technological benefits of exploring space, of visiting other planets, of putting rovers on the surfaces equipped to analyse the environment, but colonising other planets is for the birds in my mind!

Would it not be more sensible, more realistic and more practicable to visit our nearest neighbours, maybe even with manned flight which stretches the current technologies and has major spin offs to our planet rather than try to solve the gargantuan logistics of supporting a planetary colony?

The idea smacks of running away from our own, and I would want to employ our not insignificant skills in solving some of the issues on our own planet, whilst pushing the technology envelope in a pragrmatic and practical way in parallel.

 

[lifeonmercury]

Would starting a self-sustaining colony of intelligent robots on Mars be a more viable option?

 

[Stavros Kiri]

Would starting a self-sustaining colony of intelligent robots on Mars be a more viable option?

That level of artificial intelligence isn't here yet, or is it?

 

[mfb]

Human-level artificial intelligence? At least decades away, with no upper limit. And the first one, if we manage to build one, will use a massive supercomputer with megawatts of power. A compact computer with human-level artificial intelligence is even more challenging. Much more advanced intelligence? If we manage to make a superintelligent computer, forget every prediction based on existing technology - the computer might be able to re-shape our world in ways we cannot even imagine.

 

[Stavros Kiri]

After the 5G internet (and 'internet of things'), by 2020, still pending the 5th generations computers, announced as a goal long time ago, still way to go ...

 

[rootone]

That level of artificial intelligence isn't here yet, or is it?

Not yet, at one point recently some kind of fully autonomous trading algorithms were tried for stock exchange trading.
It didn't work as expected and caused a few problems that required human interventions to stop it doing trades that made little sense, (to human traders)

 

[lifeonmercury]

The robots don't need to be as smart as humans for the colony to survive.

 

[mfb]

We don't have a self-sufficient robot industry even with human intellectual input. Reducing the available intelligence won't help. Sure, humans can still control things from Earth, especially for long-term strategic decisions. But robots that can build everything on their own don't exist at the moment, and it is unclear when we will get to that point.

 

[Stavros Kiri]

Do you really think so? How many have tried and failed. How much effort, over millennia, has gone to create paradises or utopias.
There are really deep fundamental driver in human and natural processes that mess up such plans. No everyone wants the same end result. Are science people supposed to solve politics?
Come on, allow some techies the chance to escape the madness.

In my post the key words are "could have", in a potentiality or modality sense. Always being an optimist, ... some day, I hope.

But human nature [and race] may be contradictory and self-destructive, although hopefully it slowly changes. Scientists can make logic prevail! I do in fact like and hope to see more and more physicists etc. in countries' goverments etc., because 1+1=2, and not 1 or else, for that matter, something that most fail to see ...

I am with Elon Musk, Robert Zubrin etc. , or whoever will actually take the step to space exploration and human expansion [to space], but:
1. I would't go. I like it here better! [Of course, you never know! (never say never) ...]
2. They (we) have to be very careful, not just bold, because, with a problematic and weak earth, if these attempts fail we are all in a worse shape, and not just one but several steps behind!
3. I hate to point out the obvious, but Earth is the only known class-M planet around here that we can actually inhabit (for now)! So first secure it (as a home base) and then move further, unless we want part of humanity to get stranted or lost in space!, because Mars, Moon etc. are just planetary and orbital corpse ..., and will remain that if these experiments fail! ...

Come on, allow some techies the chance to escape the madness

I am also big tech fan, so I say ... go for it!
[Go techies ... go! ...]

 

[Al_]

Even if a colony was to provide stuff to Earth for FREE, the cost of maintaining the colony and transporting the stuff would be high.
Almost certainly much higher that producing the same stuff on Earth, unless it's something unique that can't be done on Earth.

Platinum, Palladium, Gold, Silver, Strontium, Tellurium, Indium, Neodymium, Gallium. All these can be mined and launched back to Earth in heat-shielded boxes with parachutes to land in the desert. The low gravity enables you to use small rockets and just a few kg of fuel made from Lunar water. The rockets could be re-used.
The rarety and value of the metals makes this profitable.

Rocket fuel and spares for geostationary and other Earth satellites cost a huge amount of money to lift up from Earth, but from the Moon, very little. Water for the ISS could come from the Moon much more cheaply. And, as things get going on the Moon, food, spare parts, science kit, etc.
The Moon's "high ground" position makes this profitable.

 

[mfb]

Platinum, Palladium, Gold, Silver, Strontium, Tellurium, Indium, Neodymium, Gallium. All these can be mined and launched back to Earth in heat-shielded boxes with parachutes to land in the desert.

Where are those metals easier to extract than on Earth?
The moon is like a sample of Earth's crust, but without the chemical processes to enrich some metals in some places.

 

[Al_]

That's really the central question.
Even if a colony was to provide stuff to Earth for FREE, the cost of maintaining the colony and transporting the stuff would be high.
Almost certainly much higher that producing the same stuff on Earth, unless it's something unique that can't be done on Earth.
A small manned base could provide useful scientific research, but no need of a fully self sufficient colony for that.
The argument for establishing a second home planet for humans is logical, but I think is politically unsellable except in a doomsday scenario.
Most people would I think probably prefer to see environmental degradation on Earth curtailed first,
or even uninhabitable regions on Earth made habitable, (at a fraction of the cost per inhabitant).

Also the colony could provide tourism, astronomy, and entertainment. NFL's first Lunar game! What would the TV rights for that sell for?
In a doomsay scenario, it might be too late to start.
Earth's environment is going to take WAAAAY more money to fix. Seperate problem.
The are barely any completely uninhabitable regions on Earth. People move out of places where the living is thin, to the big city or a mining town, a tourist town, etc. The Moon could become a place where people choose to live because they can make some money, have a good life, maybe try to stake a claim to some precious metals or some ice deposits. That's a colony!

 

[Al_]

Where are those metals easier to extract than on Earth?
The moon is like a sample of Earth's crust, but without the chemical processes to enrich some metals in some places.

It's not about easier or harder. It's about rarity. Platinum is mined in both easy and tough places on Earth. Gold is just on the surface sometimes, and sometimes a mine goes deep down. The easy places make more money, is all.
Metals from meteorites are likely just lying around in lumps on the Moon, there being no (recent) tectonics or volcanoes to cover it.

 

[mfb]

It's not about easier or harder. It's about rarity.

Rarity is exactly what makes it hard.
A cubic kilometer of average Earth's crust has gold with a worth of a billion dollars. But extracting the gold out of that would cost much more than a billion dollars.

How frequent is platinum on Moon? How much does it cost to collect and extract it? How does that compare to Earth?
You have a few asteroids on the surface, but it is unclear how efficiently you can collect them, and how much extracting the interesting metals out of them would cost.

 

[Chronos]

The value of rare commodities is market driven. Vanity items will have little utility in a space based economy compared to oxygen, water and food. We need to ponder the economic realities of a space based society before we can anticipate supply and demand. I seriously question the market value of commodities, like rare metals and gems, far from earth. What do you think a mining company would offer for a solid gold asteroid beyond the orbit of Mars?

 

[Vanadium 50]

but Earth is the only known class-M planet around here

This is Star Trek, not science.

 

[Stavros Kiri]

This is Star Trek, not science.

True as a term, but in essence means :
"Earth-like planet, the Class M designation is similar to the real-world astronomical theory of life-supporting planets within the habitable zone."
[Normally requires atmosphere "composed of nitrogen and oxygen and an abundance of liquid water necessary for carbon-based life to exist."]
(source: wikipedia)

Obviously Mars and Moon aren't ...

P.S. the above explanation in terms of Astronomical and Astrobiological terms is science ... just longer to explain or quote ...
[But truly thanks for pointing it out!]

 

[Al_]

How frequent is platinum on Moon? How much does it cost to collect and extract it? How does that compare to Earth?
You have a few asteroids on the surface, but it is unclear how efficiently you can collect them, and how much extracting the interesting metals out of them would cost.

Asteroids, and meteorites, can contain raw metals that in some cases need no extraction or processing at all.
http://www.space.com/30074-trillion-dollar-asteroid-2011-uw158-earth-flyby.html
Such things have been collecting on the Moon's surface for the last, approx 4 billion years, since most of it was last molten.
There are spectral methods that can spot elements from great distances, say from low moon orbit. Then send in the robot digger.
Compare the cost to Earth? Well, I don't know. At what stage in the deveolpment of the colony?
But don't forget - precious metal mining can be extremely profitable. Costs can be far below sales prices. Sitting on a gold mine.

 

[Al_]

What do you think a mining company would offer for a solid gold asteroid beyond the orbit of Mars?

That depends on the cost to go get it.
Which depends on satellite costs and launch costs.
Which depends on satellite tech, and if you launch from a low g place like the Moon.
So, for a Moon colony with ice mines and fuel production, basic metal bashing for satellite bodies, and imported avionics and robotics, a gold asteroid looks like a good opportunity to make some big money.

 

[Al_]

Vanity items will have little utility in a space based economy compared to oxygen, water and food.

True, so maybe the Gold gets dumped to Earth for cash, the Silver is kept for wiring, some of the Platinum for use as a catalyst and the rest dumped, and all the water ice and other volatiles kept.

 

[Al_]

You have a few asteroids on the surface

Have you seen the Moon?

 

[Al_]

The moon is like a sample of Earth's crust, but without the chemical processes to enrich some metals in some places.

Yes, and no. There were different processes, and still are. The isotopes ratios are similar, but not identical.

 

[1oldman2]

As usual Jason has put together a good piece here.
http://www.planetary.org/blogs/jason-davis/2017/20170126-moon-vs-mars-hsf.html

 

[Al_]

As usual Jason has put together a good piece here.
http://www.planetary.org/blogs/jason-davis/2017/20170126-moon-vs-mars-hsf.html

He makes a good point about the abrasive nature of Lunar dust. I think that walking on the surface will come to be seen as an emergency procedure only. Robots can be made with hard abrasion resistant exteriors and rotary joints with extremely good dust seals, even in vacuum. I'm sure in future, in space generally, they will be the outside workforce. They will either work autonomously or under Virtual Reality telepresence control from a person in a sheltered habitat or on Earth.

In fact that is one big advantage that the Moon has over Mars - the signal delay is much less. Getting a robot to the Moon is one of the easier things considered here, and if that robot has arms and the ability to work there under Earth control, we have a huge asset to help various stages of development of Lunar activity.

 

[mfb]

In fact that is one big advantage that the Moon has over Mars - the signal delay is much less. Getting a robot to the Moon is one of the easier things considered here, and if that robot has arms and the ability to work there under Earth control, we have a huge asset to help various stages of development of Lunar activity.

=> Rovers to Moon, humans to Mars?

Even when controlled by a human, current rovers cannot do many things a human can. Picking up a rock? Yes, but only with a dedicated arm to do so, and it won't work if the rock has an odd shape. Breaking the rock free first? Better have an additional arm with a hammer. Picking up dust? Another tool. Cleaning solar cells? We don't have a tool for that yet. There are to many rocks in the way? You have to go somewhere else. Wheels getting stuck? Oops. Some other part has some minor technical defect? The tool won't be useful, or in the worst case break the whole rover (e. g. solar panels that don't deploy).

 

[1oldman2]

I realize the following pushes the limits of acceptable sources for this thread, I did find it relevant (as well as a little dated) enough to mention it though.
Its just possible there may be some points worthy of discussion as its in the general subject area of the thread.
http://blogs.discovermagazine.com/crux/2014/09/08/where-build-off-world-colonies/

 

[nikkkom]

Asteroids, and meteorites, can contain raw metals that in some cases need no extraction or processing at all.

These metals are usually Fe and Ni. We have them here on Earth in abundance. Even if pure Ni is lying on the Moon, merely packing it up and sending to Earth would cost more than producing it from Earth's ores.

But don't forget - precious metal mining can be extremely profitable. Costs can be far below sales prices.

Handwavium with not a shred of calculations. Show us reasonable economic estimates that any metal on the Moon is profitable to extract and sell on Earth.

 

[Stavros Kiri]

I realize the following pushes the limits of acceptable sources for this thread, I did find it relevant (as well as a little dated) enough to mention it though.
Its just possible there may be some points worthy of discussion as its in the general subject area of the thread.
http://blogs.discovermagazine.com/crux/2014/09/08/where-build-off-world-colonies/

Some interesting points there. Is the part about Venus reasonable though? Also, with just 0.38 of Earth's gravity on martian surface, they fail to mention that this creates also a problem for the atmosphere to be terraformed (something that needs to be dealt ...) , as discussed previously here about gravity on Mars (etc.) ...

 

[mfb]

The gravity of Mars is sufficient to keep the atmosphere. Over millions of years, we would probably want an artificial magnetic field to reduce losses due to solar wind, but that is irrelevant today. If humans are still around in a million years, they will solve that issue with technologies we cannot even imagine today.

The lower gravity and the lack of a magnetic field are no obstacles to terraforming.

http://blogs.discovermagazine.com/crux/2014/09/08/where-build-off-world-colonies/

The article is completely outdated in terms of plans to go to Mars.

 

[1oldman2]

The article is completely outdated in terms of plans to go to Mars.

True, thus my disclaimer. "I realize the following pushes the limits of acceptable sources for this thread, I did find it relevant (as well as a little dated) enough to mention it though. "
I do have to admit to a certain amount of "literary License" in post #343 but after reading some of the earlier posts regarding Nuking martian moons and comparing martian colonies to Dubai, well I figured what the hell... "Its just possible there may be some points worthy of discussion as its in the general subject area of the thread."

 

[1oldman2]

Some interesting points there. Is the part about Venus reasonable though? Also, with just 0.38 of Earth's gravity on martian surface, they fail to mention that this creates also a problem for the atmosphere to be terraformed (something that needs to be dealt ...) , as discussed previously here about gravity on Mars (etc.) ...

From a personal viewpoint, I don't know enough about terraforming to comment on Mars or Venus, (either one would have to be a very long term project and I would defer to mfb's opinion on the matter.) As for Mars it seems there are some environmental conundrums that science needs to work out besides the atmosphere, radiation, perchlorates (https://phys.org/news/2015-06-future-issues-perchlorate-poses-colonizing.html), transportation etc. For example there doesn't appear to be an explanation for, https://www.nasa.gov/feature/jpl/nasas-curiosity-rover-sharpens-paradox-of-ancient-mars
"Mars scientists are wrestling with a problem. Ample evidence says ancient Mars was sometimes wet, with water flowing and pooling on the planet's surface. Yet, the ancient sun was about one-third less warm and climate modelers struggle to produce scenarios that get the surface of Mars warm enough for keeping water unfrozen."

"We've been particularly struck with the absence of carbonate minerals in sedimentary rock the rover has examined," said Thomas Bristow of NASA's Ames Research Center, Moffett Field, California. "It would be really hard to get liquid water even if there were a hundred times more carbon dioxide in the atmosphere than what the mineral evidence in the rock tells us." Bristow is the principal investigator for the Chemistry and Mineralogy (CheMin) instrument on Curiosity and lead author of the study being published this week in the Proceedings of the National Academy of Science.

 

[Stavros Kiri]

The gravity of Mars is sufficient to keep the atmosphere.

How do you justify that? [If you already have earlier and I missed it you can just quote it ... ; it's been a long discussion ...] Are you sure that with a little over 1/3 of the gravity on Earth we can have on Mars a thick and high enough earth-like-terraformable atmosphere (including ozon layer etc ...)? I haven't done the math.

 

[nikkkom]

How do you justify that? [If you already have earlier and I missed it you can just quote it ... ; it's been a long discussion ...] Are you sure that with a little over 1/3 of the gravity on Earth we can have on Mars a thick and high enough earth-like-terraformable atmosphere (including ozon layer etc ...)? I haven't done the math.

The existence of current Mars atmosphere is a proof that rate of escape is low enough.

The key here is that thicker atmosphere, at the same temperature, generally does not escape faster than a thin one (as long as mean free path at the surface is such that molecules can't escape directly from surface).
IOW: if you add CO2 to Mars so that you have 1 bar pressure at the surface, this thicker atmosphere will survive for hundreds of millions of years, if not billions.
(O2/N2 atmosphere will evaporate somewhat faster, because these molecules are lighter than CO2.)