New Mars Forums

You bring up a good point about temperature.  Generally cementious type materials lose the ability to form good bonds
if the temperature goes below 40 F.  As far as heating goes, you might want to use enclosures with electric heating elements to maintain the temperature somewhere between 60 and 80 F if you use the standard Portland type cement materials.  You can also add "antifreeze" admixtures to the concrete/mortar to insure that it sets up at a lower temperature.  Good point about moisture loss also.  You don't want to lose water very quickly or the strength of the concrete goes down.  Your probably right in that such a structure might have to be built and allowed to cure under a properly heated/pressurized "tent."  I get the feeling Martian construction will chuck many of the standards and practices we use here on Earth and develop its own unique building methods.

Taking Martian gravity into consideration, I'm not sure if an outer retaining wall would be absolutely necessary, but you'd probably need a lot more soil to make up for the tendency of material to just slump out horizontally when it's piled up.  It might be ideal to build something like this inside a huge crater because then you'd have natural  retaining walls enclosing the structure.  Or you could just dig a massive pit in the ground and then fill it back in once you build the structure considering your going to have to dig one anyway to get the covering material.

It'd be nice to see NASA or somebody else try to seriously attempt to develop some of the more technologically exotic ideas floating around.  I think the reason a lot of people, including a number of spaceflight enthusiasts, find the International Space Station such a boring waste of time and money is because it just has that "been there, done that" feel to it.  I'd whole heartedly support taking the money that goes into dubious projects like the space station and instead use it to do heavy research and development on technology and science that pushes the envelope.  Either that or we can just take about 2/3 of the Pentagon's budget and fund such projects with that instead.

Wow, I had no idea they were planning to build robotic probes that flew by flapping wings.  I'd love to see one of these things in action.  I wonder if such a design could be scaled up into a craft capable of transporting human passengers.  Flying in something like that would feel truly alien.  Who knows, in the distant future when someone mentions Mars, entomopters might spring to mind since these vehicle will probably be unique to Mars.

I'd be willing to bet the military budget could be cut by a third, probably two-thirds, and we'd still have the biggest, most powerful killing machine on the planet.  I hate to see the military given such a bloated budget at the expense of good research projects like that super collider they were going to build in Texas, etc.  Of course, being the semi-pacifist that I am, I'd much rather see money being funneled into pure research and "civilian" technology than to build some stupid bomber.

One of the advantages of having a randomly selected Duma is that such a body wouldn't have to pander to wealthy, self-interested groups in order to campaign for office.   It would also prevent self-interested groups from convincing their own puppets to run for office since the drawing would be purely random.  I don't think the framers of the Constitution, as you hinted at, thought we'd have Phillips Morris and Enron bankrolling candidates that are more interesting in protecting Corporate America than they are in protecting the rights of citizens.

Updated by Moderator 2021/09/22

      I'm gonna have to check out this article.  If this machine actually has the potential to reduce the weight of objects in an economical way it'll probably turn out to have as big of an impact on space exploration as the liquid fueled rocket engine did.  A gravity reducing machine might make delivering payloads to space via railguns a good possibility and thus very cheap.  It feels a little odd talking about it because it has that pseudo-science feel about it, but it's best to keep an open mind.  Who knows, when gravity becomes well understood we'll probably be able to control it as easily as we control electricity.

Updated by Moderator 2021/09/22

      If your numbers pan out I get the feeling that Phobos will ultimately prove more valuable in outfitting missions to mine
the asteroid belt than Mars itself will be.  Phobos's practically non-existant gravity and composition make it that much more economical.  I had never thought of extracting water from Phobos, if that turns out feasible, it might be better to just create a small space station around Mars for the purpose of agriculture if missions to the asteroid belt and beyond become manned and routine.

Updated by Moderator 2021/09/22

   The only way I can think of to inflate a dome would be to use powerful aircompressors, particularly if its very large. One of the problems I wonder about is how to insure that the you have the proper ratio of oxygen, etc, if you compress the air directly out of the Martian atmosphere.  I guess once you set up the proper air pressure you could introduce plant life into the dome to process the atmosphere, but it seems that if you want the dome to be inhabitable the instant you build it you'll have to bring along a giant aerosol can full of the proper air mixture you need.  In addition, since these aircompressors will probably have to always be working to compensate for leakage, it seems you'll have to insure that they don't poison the air with excess carbon dioxide.  As far as whether to use strips or one giant sheet of material to build the domes out of, I think strips would be the most practical way since, like you said, it would be difficult to manufacture and handle a giant sheet of material especially if your going to build something large enough to house an entire town.  I think with the use of epoxies and sealants the strips could be made nearly as leakproof as if you had one giant sheet composing the dome.

    I didn't realize Mars was mostly bedrock.  Yeah, that would definately make compaction a mute point.  I had often wondered about soil on Mars given that it hasn't had 5 billion years worth of abundant life living and decomposing on its surface.  I think I see what you mean about the adjacent holes inside the perimeter of the trenches to keep the dome
staked to the ground.  I had often thought that a way to build domes would be to build a light weight frame on which to tack strips of the enclosing materials, something similiar to a tent frame. 

    I like that image of laying back on a hammock and looking up into the night sky to see Earth and the moons.  I imagine Earth would appear to be a bright blue star.  Would you be able to see both Deimos and Phobos at the same time?  Since you mentioned only Phobos, I kinda get the feeling my question has already been answered.

Building massive vehicles which amount to houses on wheels would have very good uses for exploration or prospecting purposes but I'm not sure if they'd be practical for colonists who have no great need to frequently roam long
distances from any one place.  I imagine the energy and materials that would go into producing and running one would better be spent on building a permanent colony.  I like the maglev idea however.  They'd probably be a more efficient and safer means of running around Mars than through the use of private transportation, at least in the beginning.  Come to think of it, these giant Winnebagos would be perfect for housing the crews that lay down the tracks for the maglevs.

One of the reasons I like domes is that they seem to be the easiest way to encapsulate large areas of land.  I imagine they'd also be more efficient at keeping air inside instead of allowing it to leak out.  Not only does it seem like it would be more work to build extremely large "brick and mortar" type structures, but despite all the caulk you take along, they'd probably require more energy to keep the atmosphere up to specs due to leakage.  I think a combination of the two is the best since the vault-like buildings could end up being necessary to protect colonists from radiation (would that be a problem on Mars?) Then again I guess you could just take prefabricated buildings parts and assemble them.

Even though I can't really defend myself with any facts, I get the feeling a transparent dome would be better from a psychological standpoint than an opaque one, especially if the dome is meant to cover a large area such as enough to cover a small town.

Whenever I tried to register and edit my profile I kept running into the error "Cannot Open File:  Calendar.cfg (no such directory or file)."  It still let me register but the program
didn't indicate that I had successfully registered since it threw up that error.  It wasn't until I tried to re-register that I realized that the program had in fact successfully registered me.  Might be something for you to look into.