Author Topic: The best ways to get around Mars  (Read 124583 times)

Offline MP99

Re: The best ways to get around Mars
« Reply #20 on: 08/22/2013 05:58 AM »
I dont like the idea of wasting water just to burn it (as methalox) in I/C engines.

Carbon dioxide can be broken down to carbon monoxide and oxygen, and will burn - though not as good as methalox. Feedstock is easy to gather straight from the atmosphere, of course.

I'd prefer to see this used for powering the rolligons.

Well you're free to disagree with Steven on the matter, Martin.  I was under the impression that he was counting on a prodigious energy source, like nuclear power, to allow large-scale ISRU.  I also was under the impression that Mars the water wouldn't be escaping Mars' atmosphere any more than it does today.  There are Cirrus clouds over Mars for a reason, after all!  I will agree that Carbon Monoxide-Oxygen engine would be an easier thing to resupply though. 

I believe that water is a "fossil"resource, like oil here, not renewable like water here. Will replenish slowly, if at all. [Edit: or expensive to ship in, as above.]

Question, therefore, is whether "wasting" water to make rolligon fuel would hasten the day when water is exhausted at a location and the settlement has to abandon the area and move on.

Cheers, Martin
« Last Edit: 08/22/2013 06:00 AM by MP99 »

Offline QuantumG

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Re: The best ways to get around Mars
« Reply #21 on: 08/22/2013 09:21 AM »
Why? There's water cycle on the Moon, why wouldn't there be one on Mars?
I hear those things are awfully loud. It glides as softly as a cloud. What's it called? Monowhale!

Offline guckyfan

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Re: The best ways to get around Mars
« Reply #22 on: 08/22/2013 09:34 AM »
I believe that water is a "fossil"resource, like oil here, not renewable like water here. Will replenish slowly, if at all. [Edit: or expensive to ship in, as above.]

.............

Cheers, Martin
Why? There's water cycle on the Moon, why wouldn't there be one on Mars?

I believe, both is right. It is a limited resource locally, as water ice in the ground. This resource will not be replenished in any meaningful way.

But the water will eventually freeze out as a reusable resource at the pole caps. As it is more difficult to get water from the poles rather than from a source near the research station or settlement it would be sensible to use local water as little as possible.

Once an extended industry is established, getting water from the poles may be feasible and become necessary sooner or later. But even then it will be easier to set up settlements or camps when local water is available.


Offline gbaikie

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Re: The best ways to get around Mars
« Reply #23 on: 08/22/2013 09:54 AM »
I dont like the idea of wasting water just to burn it (as methalox) in I/C engines.

Carbon dioxide can be broken down to carbon monoxide and oxygen, and will burn - though not as good as methalox. Feedstock is easy to gather straight from the atmosphere, of course.

I'd prefer to see this used for powering the rolligons.

Well you're free to disagree with Steven on the matter, Martin.  I was under the impression that he was counting on a prodigious energy source, like nuclear power, to allow large-scale ISRU.  I also was under the impression that Mars the water wouldn't be escaping Mars' atmosphere any more than it does today.  There are Cirrus clouds over Mars for a reason, after all!  I will agree that Carbon Monoxide-Oxygen engine would be an easier thing to resupply though. 

I believe that water is a "fossil"resource, like oil here, not renewable like water here. Will replenish slowly, if at all. [Edit: or expensive to ship in, as above.]

Question, therefore, is whether "wasting" water to make rolligon fuel would hasten the day when water is exhausted at a location and the settlement has to abandon the area and move on.

Cheers, Martin
Say you have an asteroid which 400 meter in diameter. That is about 33 million cubic meters. Or about 50 million tons and if 5% is water, then 2.5 million tons of water. If you consider that the water is worth $1 per kg, then it's 2.5 trillion billion dollars of water.
There is probably more than 100 space rocks which are 400 meter in diameter or larger, and have 5% water, and would require less than 100 billion dollars to move so hits Mars at velocity that most of the water would not escape from Mars after impacting and vaporizing.

So in terms of the planet Mars, one could restore water to the planet for less than $1 per kg. And most likely do for far less than $1 per kg.
Of course I don't mean delivering water to people for such a price.

On Mars it thought there vast areas of frozen water with high concentration- permafrost/frozen mud.
Wiki:
 "A significant amount of surface hydrogen has been observed globally by the Mars Odyssey Neutron Spectrometer and Gamma Ray Spectrometer. This hydrogen is thought to be incorporated into the molecular structure of ice, and through stoichiometric calculations the observed fluxes have been converted into concentrations of water ice in the upper meter of the Martian surface. This process has revealed that ice is both widespread and abundant on the modern surface. Below 60 degrees of latitude, ice is concentrated in several regional patches, particularly around the Elysium volcanoes, Terra Sabaea, and northwest of Terra Sirenum, and exists in concentrations up to 18% ice in the subsurface. However, above 60 degrees latitude, ice is highly abundant. Polewards on 70 degrees of latitude, ice concentrations exceed 25% almost everywhere, and approach 100% at the poles."

Obviously one could find liquid water on Mars, but suppose one were doing it the hard way, and getting 20% concentration in 1 meter deep by 1 km square area. So 20 cm of water per one meter depth. So that's .2 million tons of water in 1 km square area. The next meter down might have as much or more.
Mars is nearly a vacuum, if make it more of vacuum, H20 will boil at 1 C.
So the hard part making an area having a slight vacuum and having enough thermal energy to boil water- the latent energy of: 2,270 kJ/kg.
So per square meter one has 200 kg of water: 454 million joules.
Suppose one has 600 watts of sunlight: assume it can give 400 watts of thermal heat. So in a hour: 1.44 million joules of heat per square meter.
And in month there is 720 hours. And say 1/3 is useful daylight: 240 hours. So enough energy in less than 2 months. And this just sunlight- one concentrate the sunlight to speed it up.
So cover and seal the vast area of 1 km, with fans suck atmosphere out and in daylight one with the fans, one would draw out water vapor. And in two month get about .2 million tons of water.

So on earth we have 14.7 psi or 1000 mb and Mars is 0.087 psi or 6.36 mb. 12" square window of container which had vacuum on earth would have 144 times 14.7. Or 2116.8 lbs of force. Same thing on Mars has 144 times 0.087 is 12.5 lbs of force.
A brick on Earth weighs about 6 lb. The force of complete vacuum on Mars would same as placing 2 bricks on 12" square piece of glass on Earth.
Hmm. More than thought:). What is it for square km. "Km: 10,763,910.417 Sq. Feet"-  http://www.asknumbers.com/square-kilometer-to-square-feet.aspx  Times 12.5 is 135.5 million lbs of force.
Wow. So, need smaller "boxes". And might not need to make a complete vacuum- but even 1/2 pressure it's 60+ million lb of force.
So you use separate boxes which are 10 meter square or less. 100 square meters being 1/10,000th of force. Which 13,550 lb of force. Doable.
So 1 meter square glass/plastic framed in steel support. Each 1 sq meter
getting 135.5 lb of force. And to require less strength of steel support have jacks in middle area [3 meter square area in middle] reducing span that bearing load from 10 meter to less than 4 meter. And weight of structure plus weight of atmosphere should seal it.
So box could be 6" or less in height. So each side could be 1/8" thick aluminum 12 cm by 10 meters. And 10 meter circumference is 3.18 meter diameter- and probably made into tighter circle if needed. Braces don't need to longer than 4 meter in length and something like 1 cm by 4 cm.
Plexiglass- about 1/2 ton of it. So whole thing somewhere around 1 ton or more.
So 1 km in two months makes .2 million tonnes. 10 meter square is 1/10,000 of that area.  So 10 meter square make 20 tons of water in about 2 months.
So to your question. With something like the above, one probably put in a area, and a few days or week, and then you would move it. And would dry the surface of area it was on down to by less than a foot. You could remove the dried regolith, and thereby dry lower in depth. Or simply go to different location. And seems that within a year or so the dried area would collect more water. Or if wanted wanted to dig, could you remove the dried area and dig down to bedrock.
Sometimes the Mars surface ices over with thin frost:
http://www.nasa.gov/multimedia/imagegallery/image_feature_1160.html#.UhXe1H9FbzY
So that tend to make a dry area, damper. But just small amount vapor and atmospheric pressure should also allow it to collect more moisture if given enough time.
« Last Edit: 08/22/2013 07:03 PM by gbaikie »

Offline MP99

Re: The best ways to get around Mars
« Reply #24 on: 08/22/2013 11:50 AM »
First para - billion, not trillion.

And it's only worth that if someone is willing to invest $2.5b, otherwise you flood the market. (Flood the market, get it? Ah, OK, never mind, then.)

Cheers, Martin
« Last Edit: 08/22/2013 11:53 AM by MP99 »

Offline Dalhousie

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Re: The best ways to get around Mars
« Reply #25 on: 08/22/2013 12:03 PM »
How limited is limited?

We don't know how thick the water ice layer is, but we know it is probably everywhere within a couple of metres of the surface (or less).  Assuming it's two metres thick about averages 50% of the regolith that's a million tonnes per square km.  That's 111111 tonnes of hydrogen.  Reacted with CO2 it would make 444444 tonnes of methane.

If the ice is 5 m thick it would produce over 1.1 million tonnes of methane.  I am not sure what scale production we envisage, but that is substantial. That's about twice Australia's (population 23 million) consumption of LNG last year

That water is not lost either, it ends up in the atmosphere and will freeze out at the poles. You could of course mine the polar caps which are nearly pure ice several km thick.  One square km mined to a depth of 10 m would produce over 4.4 million tonnes of methane. 

I suspect there would be a market for both CO and methane as fuels.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline gbaikie

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Re: The best ways to get around Mars
« Reply #26 on: 08/22/2013 07:24 PM »
First para - billion, not trillion.

And it's only worth that if someone is willing to invest $2.5b, otherwise you flood the market. (Flood the market, get it? Ah, OK, never mind, then.)

Cheers, Martin

Corrected. Thanks.
And said this is only adding water to planet Mars, not delivering to persons or parties. The money amount is to illustrate the effort involved. Or no one makes billions or trillions of dollars by adding water to Mars- unless some government is paying for this to be done [probably unwise and unnecessary government program].

Just saying fairly cheap [little effort per quantity added] to add water to Mars by directing an impactor- as most asteroids have some water. At Mars distance should be more water in asteroids than Earth distance and more asteroids are near Mars as compared to near Earth.
One could plan to add water to Mars via impactors, or one have impactor crashed on Mars for other reasons, and as byproduct of doing this, add water.
Earth's oceans are thought to be created by two process, active plate tectonic and asteroid impacts.
Mars lacks plate tectonic activity- and this could explain Mars lack water because beneath it's surface in it's thick mantle.
« Last Edit: 08/22/2013 07:33 PM by gbaikie »

Offline Hyperion5

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Re: The best ways to get around Mars
« Reply #27 on: 08/22/2013 11:19 PM »
So let's say it's been two decades after first landfall and we've got some substantial infrastructure in place.  The martian authorities discover a big deposit of water 150 km away and decide they need to build a settlement nearby.  What's the best way of both taking materials and the power required to build it there? 

CO/O2-powered trucks?
Methalox-powered trucks?
Electric trucks? 
CO/O2-powered trains?
Methalox-powered trains?
Electric trains? 
Nuclear-powered trains? 

Now I know what you're thinking--that last one sounds crazy.  But bear in mind, you can set rails to whatever gauge you want on Mars!  A nuclear-powered locomotive or two would give you complete operating independence, allowing rapid construction of the line there, massive haul capacity, no worries about resupply, and it'd be able to power the settlement up in the early days before it's connected to the grid.  I wouldn't use it for much else, but there is something to be said for taking a massive, reliable source of power with you to the building site.  I've said my part, so I'll let everyone else conjecture as to the best way to bring a settlement into being using martian transport means. 

Offline Dalhousie

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Re: The best ways to get around Mars
« Reply #28 on: 08/23/2013 01:15 AM »
So let's say it's been two decades after first landfall and we've got some substantial infrastructure in place.  The martian authorities discover a big deposit of water 150 km away and decide they need to build a settlement nearby.  What's the best way of both taking materials and the power required to build it there? 

CO/O2-powered trucks?
Methalox-powered trucks?
Electric trucks? 
CO/O2-powered trains?
Methalox-powered trains?
Electric trains? 
Nuclear-powered trains? 

Now I know what you're thinking--that last one sounds crazy.  But bear in mind, you can set rails to whatever gauge you want on Mars!  A nuclear-powered locomotive or two would give you complete operating independence, allowing rapid construction of the line there, massive haul capacity, no worries about resupply, and it'd be able to power the settlement up in the early days before it's connected to the grid.  I wouldn't use it for much else, but there is something to be said for taking a massive, reliable source of power with you to the building site.  I've said my part, so I'll let everyone else conjecture as to the best way to bring a settlement into being using martian transport means. 

It depends on how much you want to move over what period of time.  But only 20 years after landing I would go for trucks. Terrestrial road rains can move 250 tonnes over fairly basic roads, on Mars they could move a lot more.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Hyperion5

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Re: The best ways to get around Mars
« Reply #29 on: 08/23/2013 01:53 AM »
So let's say it's been two decades after first landfall and we've got some substantial infrastructure in place.  The martian authorities discover a big deposit of water 150 km away and decide they need to build a settlement nearby.  What's the best way of both taking materials and the power required to build it there? 

CO/O2-powered trucks?
Methalox-powered trucks?
Electric trucks? 
CO/O2-powered trains?
Methalox-powered trains?
Electric trains? 
Nuclear-powered trains? 

Now I know what you're thinking--that last one sounds crazy.  But bear in mind, you can set rails to whatever gauge you want on Mars!  A nuclear-powered locomotive or two would give you complete operating independence, allowing rapid construction of the line there, massive haul capacity, no worries about resupply, and it'd be able to power the settlement up in the early days before it's connected to the grid.  I wouldn't use it for much else, but there is something to be said for taking a massive, reliable source of power with you to the building site.  I've said my part, so I'll let everyone else conjecture as to the best way to bring a settlement into being using martian transport means. 

It depends on how much you want to move over what period of time.  But only 20 years after landing I would go for trucks. Terrestrial road rains can move 250 tonnes over fairly basic roads, on Mars they could move a lot more.

I forgot that, given you could make martian roads however big you wanted, that it should be possible to haul some really big items by road.  You might even be able to haul a small nuclear reactor across the martian plains provided you had a big enough truck.  Btw, since you mention road trains and trucks, just how big ought the standardized size of martian trucks ought to be?  Surely they'd be more efficient if they were larger than they are on Earth, no? 

For everyone's enjoyment, I've attached an image of how a martian nuclear locomotive might look that I can only wish I'd drawn.  He gets a big thumbs up for the "Hyperion" splashed across the design.  :) 

Offline gbaikie

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Re: The best ways to get around Mars
« Reply #30 on: 08/23/2013 02:25 AM »
So let's say it's been two decades after first landfall and we've got some substantial infrastructure in place.  The martian authorities discover a big deposit of water 150 km away and decide they need to build a settlement nearby.  What's the best way of both taking materials and the power required to build it there? 

CO/O2-powered trucks?
Methalox-powered trucks?
Electric trucks? 
CO/O2-powered trains?
Methalox-powered trains?
Electric trains? 
Nuclear-powered trains? 

Now I know what you're thinking--that last one sounds crazy.  But bear in mind, you can set rails to whatever gauge you want on Mars!  A nuclear-powered locomotive or two would give you complete operating independence, allowing rapid construction of the line there, massive haul capacity, no worries about resupply, and it'd be able to power the settlement up in the early days before it's connected to the grid.  I wouldn't use it for much else, but there is something to be said for taking a massive, reliable source of power with you to the building site.  I've said my part, so I'll let everyone else conjecture as to the best way to bring a settlement into being using martian transport means. 

Pipes.

Offline Dalhousie

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Re: The best ways to get around Mars
« Reply #31 on: 08/23/2013 02:44 AM »
Btw, since you mention road trains and trucks, just how big ought the standardized size of martian trucks ought to be?  Surely they'd be more efficient if they were larger than they are on Earth, no? 

On Earth we have light, medium and heavy rigid trucks, all can come with a dog and trailer and all wheel drive.  Then we go to the articulated trucks, add trailers and you have road trains.

The main dimension limits for trucks Earth are to do with infrastructure, widths and axle loadings, also length.  These might be relaxed on Mars.  After all you can carry nearly three times the mass for the same loading, or therabouts.  I suspect width would be greater, because of the need for greater stability.

A lot depends on rolling resistance too.  Ifroads can be made that allow low rolling resistance then articlated trucks would be attractive.  if not, then there would be a need for large all wheel drive vehicles, perhaps not unlike the large Russian rocket carriers.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Dalhousie

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Re: The best ways to get around Mars
« Reply #32 on: 08/23/2013 02:45 AM »
Pipes.

Good suggestion! Any idea on the economics of pipelines, as opposed to rail or road?
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline spectre9

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Re: The best ways to get around Mars
« Reply #33 on: 08/23/2013 08:19 AM »
I still like my trucks that run on overhead power lines.

You can't just burn oxygen like on Earth which means you either carry oxidizer or you carry batteries.

Why not just transmit the energy from a far away power plant?

That way you could run on nuclear if you wanted without taking the reactor with you. Giant fields of solar panels might do the job.

Why not a train?

Laying rail is harder than stringing a power line. I'm not sure how you would build a train line on Mars. You can't use wooden sleepers. What do you use? Metal? The expense would be enormous.

Offline gbaikie

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Re: The best ways to get around Mars
« Reply #34 on: 08/23/2013 11:31 AM »
Pipes.

Good suggestion! Any idea on the economics of pipelines, as opposed to rail or road?

Well a rail is a road [with rails:)].
And a pipe doesn't require a road.
Though obviously in some cases roads can fairly easy to make- one doesn't have make it, just drive somewhere.
Generally a road or rail can carry a wide variety of stuff. So if invest in construction of railroad it could carry people, coal, or cows. Pipes don't have such diversity of stuff transported.
But it seems if you have a lot of stuff, like lots of water to move then one would choose pipes.
Very little water is moved on Earth with rails or roads. And water pipes are generally buried.
In US, rail is cheaper than road transport. And ship transport per mile is cheapest transportation in the world.
Most oil and petroleum products in US is transported with pipeline:
http://www.aopl.org/aboutPipelines/
Probably most significant aspect with pipeline transportation is safety and
reduced rail or road traffic.
So above link 71% of oil and petroleum products is moved by pipeline, 22% is transported over water, 3% by rail and 4% by road.
So I guess if had a river [or ocean route] you might choose barge over pipeline.

An average household uses: "Americans use large quantities of water inside their homes. The average family of four can use 400 gallons of water every day, and, on average, approximately 70 percent of that water is used indoors."
http://www.epa.gov/WaterSense/pubs/indoor.html
A gallon of water is 8.34 lbs. 400 gallon is 3336 lbs.
If wanted it, one get about 20 gallons a minute or 28820 gallons [240,192 lbs] a day.
From say 3/4 inch pipe at +60 psi.

As for on Mars.
Probably wouldn't need to bury it if it's a constant
flow.
Actually come to think of it, burying it could be more of problem,
because on Earth under ground is usually above freezing and constant
temperature. Mars underground may be well below freezing as it's constant temperature.
You could use larger pipe and lower pressure.
So, you could use clay pipe.
So needing kiln and pipe length depends on kiln size.

You have lots of iron on Red Mars. Iron doesn't require much energy to make and one could make longer lengths so that would make building pipeline easier than clay.
And if have a modest settlement you would making steel/iron in simple shapes [plate, rods, wire for cable] and making pipe would also be fairly simple fabrication.
 
« Last Edit: 08/23/2013 11:37 AM by gbaikie »

Offline MP99

Re: The best ways to get around Mars
« Reply #35 on: 08/23/2013 11:36 AM »
So let's say it's been two decades after first landfall and we've got some substantial infrastructure in place.  The martian authorities discover a big deposit of water 150 km away and decide they need to build a settlement nearby.  What's the best way of both taking materials and the power required to build it there? 

CO/O2-powered trucks?
Methalox-powered trucks?
Electric trucks? 
CO/O2-powered trains?
Methalox-powered trains?
Electric trains? 
Nuclear-powered trains? 

Now I know what you're thinking--that last one sounds crazy.  But bear in mind, you can set rails to whatever gauge you want on Mars!  A nuclear-powered locomotive or two would give you complete operating independence, allowing rapid construction of the line there, massive haul capacity, no worries about resupply, and it'd be able to power the settlement up in the early days before it's connected to the grid.  I wouldn't use it for much else, but there is something to be said for taking a massive, reliable source of power with you to the building site.  I've said my part, so I'll let everyone else conjecture as to the best way to bring a settlement into being using martian transport means. 

Pipes.

Avg temp is below zero, so water in pipes would freeze, I'd think?

Cheers, Martin

Offline Hyperion5

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Re: The best ways to get around Mars
« Reply #36 on: 08/23/2013 04:15 PM »
I still like my trucks that run on overhead power lines.

You can't just burn oxygen like on Earth which means you either carry oxidizer or you carry batteries.

Why not just transmit the energy from a far away power plant?

That way you could run on nuclear if you wanted without taking the reactor with you. Giant fields of solar panels might do the job.

Why not a train?

Laying rail is harder than stringing a power line. I'm not sure how you would build a train line on Mars. You can't use wooden sleepers. What do you use? Metal? The expense would be enormous.

Oh I don't think so.  Here's a bit of NASA testimony about martian soil:

"If you look at the soil composition of Mars, the one thing that really strikes you is that it's 5 to 14 percent iron oxide," said Dr. Peter Curreri, a materials scientist at NASA's Marshall Space Flight Center. "It's almost ore-grade material."


http://science1.nasa.gov/science-news/science-at-nasa/1999/msad03mar99_1/

While I won't say it will be no problem producing steel on Mars, it will be far easier to produce than almost anything else and probably pretty cheap.  As it happens railroads use steel tracks and a number use modern steel ties.  Steel ties are lighter in weight than concrete and able to stack in compact bundles unlike timber. Steel ties can be installed onto the existing ballast, unlike concrete ties which require a full depth of new ballast. Steel ties are 100% recyclable and require up to 60% less ballast than concrete ties and up to 45% less than wood ties.  So all in all, I don't see where the enormous expense is coming in if the building materials are all around.  In fact, you can make a good argument that even if Mars did have a wet climate and trees, they'd still be the best option available. 


Online Robotbeat

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Re: The best ways to get around Mars
« Reply #37 on: 08/23/2013 05:59 PM »
There's a heck of a lot of meteoric iron sitting right on the surface in plain view. Doesn't even have to be refined necessarily.

But yeah, you can use concrete (or something similar) for ties.
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Offline Hyperion5

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Re: The best ways to get around Mars
« Reply #38 on: 08/23/2013 10:41 PM »
There's a heck of a lot of meteoric iron sitting right on the surface in plain view. Doesn't even have to be refined necessarily.

But yeah, you can use concrete (or something similar) for ties.

Now I know Mars has a thin atmosphere and you might be able to use a water-ammonia mix to go along with your aggregate and cement (Calcium Oxide & sand/dirt) mix to create concrete (especially indoors).  The issue with building a road with concrete are the temperatures seen on Mars.  I've seen people mention that builders in Antarctica avoid using concrete whenever possible because it's less than an ideal building material for their extremely cold environment.  Now although Mars and Antarctica share a similarly cold climate (remarkably similar in temperatures in places), I'm not sure how big a difference that much thinner atmosphere will make.  One would think that getting your martian concrete to set would be a tough thing to pull off.  Steel, in contrast, can be made indoors and endlessly recycled. 

Railroad ties might be a different matter if you poured them indoors and then let them set a few days before transporting them to the rail line.  The key is figuring out how to find the right mixture of materials that are common on Mars and can substitute for limestone. 
« Last Edit: 08/23/2013 10:47 PM by Hyperion5 »

Offline RocketmanUS

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Re: The best ways to get around Mars
« Reply #39 on: 08/24/2013 01:17 AM »
Railways and tunnels only go between to points.
Off road vehicles go in all directions there is ground under them.
So use trucks with trailers behind them.
No maintenance of rails or tubes. Just smooth out the path and if it is damaged could just go around it till fixed later unlike a damaged rail track.

Easy to move a small colony if there is not to much infrastructure.

At some point if the population grow and there was to colonizes to go between or and space port then they might install a tunnel made if iron ( seems to be plenty of that lying around ). Large enough diameter could add power lines, water, gas, ect. Don't think it would be pressurized above surface atmospheric pressure.

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