# Big Water On Mars!



## Stephen Palmer (Mar 6, 2015)

Major news, I'd say.


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## J Riff (Mar 6, 2015)

Uh-huh. Yup. Now to discover intelligent life on the Earth. )


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## BAYLOR (Mar 6, 2015)

J Riff said:


> Uh-huh. Yup. Now to discover intelligent life on the Earth. )



There's no such thing.


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## BAYLOR (Mar 6, 2015)

Stephen Palmer said:


> Major news, I'd say.



I wish that version of Mars with an ocean existed right now.


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## Harpo (Jul 25, 2018)

There's a huge subterranean lake of liquid water on Mars


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## thaddeus6th (Jul 25, 2018)

Hmm. Will we be destroyed by vengeful Martian otters, or simply the brute extermination of the Great Filter, I wonder...

Sorry, I meant, "Gosh, how exciting!"


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## night_wrtr (Jul 25, 2018)

Harpo said:


> There's a huge subterranean lake of liquid water on Mars



_"They suspect that dissolved salts from nearby minerals prevent the water from freezing, despite the low temperatures."_

Is this basically Mars' version of the Dead Sea? I wonder what the salinity level is, and if that could limit the ability for life to actually survive there...


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## Stephen Palmer (Jul 25, 2018)

There are lots of species of Archaea that love salty water.


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## Onyx (Jul 25, 2018)

...


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## mosaix (Jul 25, 2018)

Mars: huge underground lake raises prospects of life on planet, astronomers say

_Astronomers have found compelling evidence that there is a huge reservoir of liquid water buried a mile under the ice near the south pole on Mars.

Radar measurements taken from the European Space Agency’s Mars Express orbiter spotted the 12 mile-wide stretch of water at the base of a thick slab of polar ice in a region known as Planum Australe.

It is the first time that researchers have identified a stable body of liquid water on the red planet. The finding raises the likelihood that any microbial life that arose on Mars may continue to eke out a rather bleak existence deep beneath the surface._


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## Vertigo (Jul 25, 2018)

Stephen Palmer said:


> There are lots of species of Archaea that love salty water.


But, from the article, possibly not quite as salty as this is likely to be. Where apparently one of the biggest challenges would be to prevent the desiccating effect of the salt sucking all the water out of the cells.


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## Venusian Broon (Jul 25, 2018)

I've tried to find out how salty they think it is, but I can't find what sort of levels they are talking about - possibly way above 30% salinity, which is perhaps why they are somewhat negative on life's chances there!

However, one must also factor in the pressure of the ice sheet on top of these pools of water, which complicates things. Plus, just because it is minus 68 deg C on the surface, does not mean that it is minus 68 deg C down there. 

And it may not be a pocket of water like a lake, so perhaps the saltiness would not matter??? 

From Underground Lake Found on Mars? Get the Facts.
_
"But not everyone is convinced that the “lake” is actually a lake. Even according to the team, it could instead be a deposit of dampened sludge, more like muddy sediments than a pocket filled with liquid. Determining the exact nature of the structure will require a different instrument, Pettinelli says.
“We can’t choose between one or the other. We don’t have enough information to say this is a lake or saturated sediment like an aquifer,” Pettinelli says. “The lake will be more interesting.”_

Still, I think damp sludge could be interesting too.


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## Onyx (Jul 25, 2018)

Conditions that are necessary to create life from scratch could be incredibly different from conditions that life might adapt itself to. So if Mars had a warm and wet period to create life, some of it could have survived if the changes in temperature and salinity were gradual enough for evolution to keep pace. With the right evolutionary pressures you could end up with life that "flourishes" in salty permafrost.


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## Vertigo (Jul 25, 2018)

Venusian Broon said:


> I've tried to find out how salty they think it is, but I can't find what sort of levels they are talking about - possibly way above 30% salinity, which is perhaps why they are somewhat negative on life's chances there!
> 
> However, one must also factor in the pressure of the ice sheet on top of these pools of water, which complicates things. Plus, just because it is minus 68 deg C on the surface, does not mean that it is minus 68 deg C down there.
> 
> ...


Sadly it's a log colder at the surface I think. "At the bottom of the ice at the Martian south pole, the temperature is estimated to be about -68C. "

On balance I think it's possible but unlikely. I still think somewhere like Enceladus is a more likely prospect.


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## Brian G Turner (Jul 25, 2018)

I take a positive view on (eventually!) finding life throughout the universe - but I struggle to be optimistic about Mars. The only reason we seem to focus on it is because it's the nearest body, rather than because it suits any conditions conducive to life as we know it. Europa and Enceladus seem to be far, far better prospects.


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## Venusian Broon (Jul 25, 2018)

Brian G Turner said:


> I take a positive view on (eventually!) finding life throughout the universe - but I struggle to be optimistic about Mars. The only reason we seem to focus on it is because it's the nearest body, rather than because it suits any conditions conducive to life as we know it. Europa and Enceladus seem to be far, far better prospects.




The reason we focus on it, is that of all the celestial bodies that we have hard data on, it is the most suitable for us as a species to attempt to live on and terraform.

The other bodies are, I agree, are fascinating as they seem much more favourable for native species to still be around today, but would make awful colonies for us humans.


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## Onyx (Jul 25, 2018)

Venusian Broon said:


> The reason we focus on it, is that of all the celestial bodies that we have hard data on, it is the most suitable for us as a species to attempt to live on and terraform.
> 
> The other bodies are, I agree, are fascinating as they seem much more favourable for native species to still be around today, but would make awful colonies for us humans.


I really don't understand that notion. Mars is a terrible place to live. It has no magnetic protection against cosmic rays and the atmosphere is too thin to make good use of aerodynamic lift devices while being just thick enough to make ballistic space launches impractical and sandstorms a reality. The gravity is too low to effectively trap an atmosphere.

As off world bases go, the moon or other airless bodies would be better choices due to the relative ease of travel to and from and the lack of weather. If you have to live under heavy shielding anyway, why choose such a difficult place like Mars?

I think Mars is just low hanging fruit - Venus is too problematic to explore, Europa and Ganymede are in Jupiter's radiation belt, but Mars is close and presents few hazards. And we can't quite shake the feeling that it had canals and Martians - the only specific alien life word that has ever stuck. I really think the Mars thing is romantic tomfoolery. Ceres would be a much more interesting place to put people if you feel the need to get out of town.

I'd like to see more robotic exploration of Mars while we build some actual infrastructure someplace useful.


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## mosaix (Jul 25, 2018)

Venusian Broon said:


> The reason we focus on it, is that of all the celestial bodies that we have hard data on, it is the most suitable for us as a species to attempt to live on and terraform.
> 
> The other bodies are, I agree, are fascinating as they seem much more favourable for native species to still be around today, but would make awful colonies for us humans.



I agree. Also some of the pictures sent back by the rovers look like they could have been taken here on Earth. It’s probably the most ‘non-alien’ looking planet in the solar system. It’s the place we could come closest to feeling ‘at home’.


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## Robert Zwilling (Jul 26, 2018)

Until I hear a good explanation of where the life came from that inhabits deep sea hydrothermal vents I am inclined to believe there is some kind of life under the surface of Mars, the Moon and a few other locations around the gas giants. 

The life systems at hydrothermal vents make the life living in the hot springs in Yellowstone National Park look like child's play. Extremophile  just means living in a place we can't live in. It's ordinary life in extreme conditions for us, not for them. The narrow range we live in could be the exception, perhaps a place where all the rules get broken. 

The hydrothermal life either adapted to the situation, which seems likely, for how could similar looking life pop up like that. Or they started from scratch and developed without ever having seen a molecule of free oxygen, right from the get go they were using chemosynthesis to get what was available. Either way it shows a versatility we're having a hard time imagining. That's the problem, it's there whether we can prove it or not. If you want cold with some pressure there's always the life carving out an existence in the undersea methane hydrate deposits. 

Once life gets started it might be very hard to kill it at the single cell level. Macro stuff like us are probably just flowers off a budding blob that's been in existence for 4 billion years. The smaller stuff might have builtin genetic libraries that can function and adapt to changes most anywhere in the solar system where there is water in some form, even thick perchlorate sludges that were once salty waters. 

The flip side is that this particular underground sea will turn out to be like a coal or oil deposit containing once living matter. If so, I will just continue figuring you just got to go deeper below the surface to find something living. Maybe the deeper you go the more water you find. If nothing else, they should have no problem constructing fuel cells the size of small skyscrapers on Mars. Then the contamination will follow in our footsteps the same way it ended up inside nuclear facilities and loving it.


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## Venusian Broon (Jul 26, 2018)

Onyx said:


> I really don't understand that notion. Mars is a terrible place to live. It has no magnetic protection against cosmic rays and the atmosphere is too thin to make good use of aerodynamic lift devices while being just thick enough to make ballistic space launches impractical and sandstorms a reality. The gravity is too low to effectively trap an atmosphere.
> 
> As off world bases go, the moon or other airless bodies would be better choices due to the relative ease of travel to and from and the lack of weather. If you have to live under heavy shielding anyway, why choose such a difficult place like Mars?
> 
> ...



I don't why having a place that can ballistically launch space craft easily makes it easier to live on. The Earth is pretty shockingly bad in this regard.

However, just off the top of my head:

Mar's soil contains water to extract, it's not too cold or too hot, we can use solar panels there because there's enough sunlight and it has a day/night cycle that is very similar to ours.

On top of this, although the atmosphere is thin, that still offers a modicum of protection from cosmic rays and sunlight compared to somewhere as barren as the moon/Ceres.

The gravity, again quite low, is still sufficiently large so that humans_ may_ actually be able to adapt to. Again a place like the moon may just be far too low for us to ever be healthy on - therefore a place like Cere's would be a permanent hospital for us.

From 'aesthetic' reasons Mars also wins, in my book, because of some of the factors above, it is the closest cousin to Earth - true it looks mostly like a desert - but I think a degree of familiarity would help tremendously. Again compare to the much more desolate places you've mentioned - although in those cases people would likely have to buried to protect themselves from solar radiation and other factors - so you'd just be living in boxes. (Which

While trying to make a breathable atmosphere for Mars is still SF, it doesn't require much and we wouldn't need pressure suits on the surface. Again good luck even trying to get close to that on Moon/Ceres.



> If you have to live under heavy shielding anyway, why choose such a difficult place like Mars?


 Yeah there's lots of tech you'd need to live there, but you'd need even more shielding and tech everywhere else. It's by far the _easiest _place we know to live on. I agree it's tough but that just goes to show how hostile the universe is to human life outside the Earth.

The moon itself has far fewer vital resources, problems with it's gravity as I've stated, can't be terraformed - at least with tech that we can probably come up with, and the various other points I've already brought up.

The only benefit I can really think for the moon is it's extreme closeness. However at least Mars is probably next on the list as regards contact from Earth.

If all your doing is just making an outpost that spits out spacecraft to go further into the solar system or to act as refuelling dumps for spacecraft - why have humans living there long term at all? You probably want autonomous robotic manufacturing that can be adapted to living to the much harsher conditions.

Now, you could probably make the same argument for Mars, but if humanities long term future is to get out and live on other planets (if you don't believe this, then fair enough, it's a waste of time even looking into this), Mars is a good 'practice' in how we would need to adapt and terraform.

Personally, I'd like to see us able to handle our own ecosystem first on planet Earth and learn to actually live on that without causing ecological catastrophe - the jury is still out on that. The cost of actually having to terraform an 'easy' target such as Mars and having significant numbers of humans on it is, as Neil Degrasse Tyson points out, is so huge, that it should be much easier to fix _any_ problem we have on Earth _first_.

But as a SF reader/writer and a trained scientist I can dream a little beyond this, past out troubles and imagine humans as explorers. Mars would be a good first step.


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## Justin Swanton (Jul 26, 2018)

If it's going to cost something in the region of several hundred billion to a trillion dollars to get a handful of astronauts to Mars for a short stay then I can't conceive how the Earth's economy could sustain terraforming the planet, keeping in mind it would be a gigantic expenditure of resources for no returns for hundreds of years. I just can't imagine the political will to do it, barring certain knowledge the Earth was going to die in a few centuries.

We love Mars basically because it's close and on ground level it looks rather like the Earth (love those Martian sunsets). One forgets that Mars is just as hostile to life as the Moon, and the Moon is far better for us as it is close enough to Earth for rescue missions to get there in time. It's just that there's all that white-grey rock bleached in harsh sunlight with razor-sharp black shadows, under a black and starless sky. Yuk.


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## Vertigo (Jul 26, 2018)

Robert Zwilling said:


> Until I hear a good explanation of where the life came from that inhabits deep sea hydrothermal vents I am inclined to believe there is some kind of life under the surface of Mars, the Moon and a few other locations around the gas giants.
> 
> The life systems at hydrothermal vents make the life living in the hot springs in Yellowstone National Park look like child's play. Extremophile  just means living in a place we can't live in. It's ordinary life in extreme conditions for us, not for them. The narrow range we live in could be the exception, perhaps a place where all the rules get broken.
> 
> ...


I can only recommend you read The Vital Question: Energy, Evolution, and the Origins of Complex Life by Nick Lane which addresses a number of your questions with regard to hydrothermal vents and that it is quite likely they are where life originated. The book explains the biochemistry of it far far better than I could attempt. Lane posits at the end of the book that life will be likely anywhere in the universe that has (or had) the equivalents of our hydrothermal vents (more specifically alkaline hydrothermal vents).


Justin Swanton said:


> If it's going to cost something in the region of several hundred billion to a trillion dollars to get a handful of astronauts to Mars for a short stay then I can't conceive how the Earth's economy could sustain terraforming the planet, keeping in mind it would be a gigantic expenditure of resources for no returns for hundreds of years. I just can't imagine the political will to do it, barring certain knowledge the Earth was going to die in a few centuries.
> 
> We love Mars basically because it's close and on ground level it looks rather like the Earth (love those Martian sunsets). *One forgets that Mars is just as hostile to life as the Moon*, and the Moon is far better for us as it is close enough to Earth for rescue missions to get there in time. It's just that there's all that white-grey rock bleached in harsh sunlight with razor-sharp black shadows, under a black and starless sky. Yuk.


I think @Venusian Broon quite clearly explained why Mars is less hostile than the moon. Still hostile, yes, but much less so. Another reason for that hostility would be the unweathered dust found on the moon that can be so injurious to our health, causing significant problems for all the astronauts that visited the moon's surface. As highlighted in a recent thread here on Chrons.


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## Serendipity (Jul 26, 2018)

Onyx said:


> I really don't understand that notion. Mars is a terrible place to live. It has no magnetic protection against cosmic rays and the atmosphere is too thin to make good use of aerodynamic lift devices while being just thick enough to make ballistic space launches impractical and sandstorms a reality. The gravity is too low to effectively trap an atmosphere.
> 
> As off world bases go, the moon or other airless bodies would be better choices due to the relative ease of travel to and from and the lack of weather. If you have to live under heavy shielding anyway, why choose such a difficult place like Mars?
> 
> ...


What about Callisto?


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## Serendipity (Jul 26, 2018)

Justin Swanton said:


> If it's going to cost something in the region of several hundred billion to a trillion dollars to get a handful of astronauts to Mars for a short stay then I can't conceive how the Earth's economy could sustain terraforming the planet, keeping in mind it would be a gigantic expenditure of resources for no returns for hundreds of years. I just can't imagine the political will to do it, barring certain knowledge the Earth was going to die in a few centuries.
> 
> We love Mars basically because it's close and on ground level it looks rather like the Earth (love those Martian sunsets). One forgets that Mars is just as hostile to life as the Moon, and the Moon is far better for us as it is close enough to Earth for rescue missions to get there in time. It's just that there's all that white-grey rock bleached in harsh sunlight with razor-sharp black shadows, under a black and starless sky. Yuk.



I don't dispute your current costs for getting a handful of astronauts to Mars and back in the near future. 
Farther into the future, I suspect it'll be another matter. For instance we could at the appropriate time hitch a ride on Cruithne or similar for a large part of the journey to Mars - which mitigates quite a few problems of space travel etc. 
As for terraforming Mars - it depends how long you can allow it take as to how expensive it will be.


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## Justin Swanton (Jul 26, 2018)

Vertigo said:


> I think @Venusian Broon quite clearly explained why Mars is less hostile than the moon. Still hostile, yes, but much less so. Another reason for that hostility would be the unweathered dust found on the moon that can be so injurious to our health, causing significant problems for all the astronauts that visited the moon's surface. As highlighted in a recent thread here on Chrons.




Well...



> Mars' soil contains water to extract, it's not too cold or too hot, we can use solar panels there because there's enough sunlight and it has a day/night cycle that is very similar to ours.



The Moon has plenty of water as well. If one can profitably extract from Mars one can profitably extract it from the Moon.



> On top of this, although the atmosphere is thin, that still offers a modicum of protection from cosmic rays and sunlight compared to somewhere as barren as the moon/Ceres.



Mars has no magnetic field and its atmospheric pressure is 1% Earth's, which means it provides virtually _*no*_ protection against Cosmic rays and Solar flares. You might take fractionally longer to die unprotected on Mars but that's about the only difference.



> The gravity, again quite low, is still sufficiently large so that humans_ may_ actually be able to adapt to. Again a place like the moon may just be far too low for us to ever be healthy on - therefore a place like Cere's would be a permanent hospital for us.



We don't actually know the long-term effects of low gravity on human health, just the effects of zero-gravity. Does the body cope better in 1/3 gravity or 1/6 gravity? The jury remains out.

Mars has one real problem: its soil. Less abrasive than lunar regolith it contains significant amounts of highly-reactive *perchlorate* that is probably toxic for humans (sorry Mark Watney). You don't want to breathe the stuff in for any length of time. Lunar regolith is chemically inert but very abrasive, however the lungs can cope with it at least for a few days.


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## Justin Swanton (Jul 26, 2018)

Serendipity said:


> I don't dispute your current costs for getting a handful of astronauts to Mars and back in the near future.
> Farther into the future, I suspect it'll be another matter. For instance we could at the appropriate time hitch a ride on Cruithne or similar for a large part of the journey to Mars - which mitigates quite a few problems of space travel etc.
> As for terraforming Mars - it depends how long you can allow it take as to how expensive it will be.



All scenarios for terraforming Mars involve landing a lot of large machines on the Martian surface that are capable of transforming the atmosphere - and maintaining those machines for decades or centuries whilst they do the job. I can just imagine the President's televised Message to the Nation:

"Good news folks, your taxes are going up 50% with immediate effect. At the same time we're canning public health care and anything else that looks too expensive, to initiate a two-century-long Martian terraforming project that will see your great-great-great-great-great-great-grandchildren live on Mars! Make America the Greatest Nation in the Solar System! Vote Trump!"


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## Vertigo (Jul 26, 2018)

As I understand it, the Moon is _thought _to have a fair bit of water but mainly at the poles and it's yet to be determined just how much. The presence of _some _water has been determined but not the quantity.


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## Stephen Palmer (Jul 26, 2018)

Enceladus or Europa the most likely, imo.


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## Onyx (Jul 26, 2018)

Venusian Broon said:


> I don't why having a place that can ballistically launch space craft easily makes it easier to live on. The Earth is pretty shockingly bad in this regard.


We're already on earth. And the earth is shockingly bad to get out of its gravity well. But it does have a thick enough atmosphere to assist in returning.

The ability to receive materials and to engage in trade is going to be vitally important to establish a colony of any size. A moon base with easy launch facilities isn't just a jumping off point for other exploration, but a place with the easiest access to raw materials found in other places in the solar system. And the moon appears to have some useful water, as do many asteroids. And the moon has a lot of aluminum.



Venusian Broon said:


> While trying to make a breathable atmosphere for Mars is still SF, it doesn't require much and we wouldn't need pressure suits on the surface. Again good luck even trying to get close to that on Moon/Ceres.


Mars pressure is less the tenth of the minimum pressure required for human blood to not boil - so you definitely need a pressure suit. Average Martian air pressure is about the same is 100,000 ft altitude on earth. At 100,000 feet, military pilots wear space suits and have almost no atmospheric cosmic ray protection. But at least they have the magnetosphere.


Ultimately, anyone living on Mars or the Moon is going to be living indoors. That's a necessity of the lack of cosmic ray protection in either place - plastic domes simply aren't going to cut it. And while going outside might seem more attractive on Mars, it will be an EVA that is just as serious and possibly a lot more dangerous on Mars because of factors like sandstorms, higher gravity and shifting sands. All of that makes it harder to build surface installations and maintain solar collection. The decreased effectiveness of a mass driver means a Martian colony would have to spend part of its resources on propellent to launch any sort of trade goods or mining effort outside of Mars.

So the hundreds or thousands of years required to terraform would be lived largely indoors, and that's assuming it is possible to generate an atmosphere that doesn't just boil off into space since the gravity is only .37 of Earth's. It is a real question whether even the thickest atmosphere would remain for any useful length of time.

In contrast, places with low gravity and easier access to solar energy are great places to hollow out. Excavations of city size caverns in the moon's more homogeneous soil would be possible and stable. Hollow asteroids could be built with carousels or spun themselves if sufficiently fused enough.


That's why I don't get it. The Martian atmosphere is all hazard and no reward, major projects on Mars are going to be much more difficult and the atmosphere that is there makes ferrying materials to and from the gravity well much more costly. That doesn't seem worth it to be able to look out of a several feet of glass at the Martian surfaces when you could build an indoor paradise other places. And the moon already has accessible lava tubes that could be quickly occupied. One found so far is 50km long and 100m wide.

This is what the view "out the window" of a Lunar lava tube colonist would look like:





This is the scale of what could be done over time:






Or maybe this:


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## Onyx (Jul 26, 2018)

Stephen Palmer said:


> Enceladus or Europa the most likely, imo.


The radiation belt that Europa is in is 1,000,000 times that of the dangerous portions of our Van Allen belts. Once you get far enough under the ice you'd be reasonably safe, but even operating robotic spacecraft around Europa is a problem.


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## Vertigo (Jul 26, 2018)

Onyx said:


> The radiation belt that Europa is in is 1,000,000 times that of the dangerous portions of our Van Allen belts. Once you get far enough under the ice you'd be reasonably safe, but even operating robotic spacecraft around Europa is a problem.


I think you'll find that comment was with reference to finding life rather than human habitation.


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## J Riff (Jul 27, 2018)

Oh gee, oh gosh, can we go?


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## Serendipity (Jul 27, 2018)

Oh sky-diving pussy-cats.... this thread has given me a crazy, absolutely out of the box of impossibilities that aren't, idea about how to sort out the radiation problem on Mars. Must put it into a short story.

(I'm never going to forgive C.A.T. for this... he kind of in his bumbling way, pointed the way).


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## BAYLOR (Jul 28, 2018)

To make Mars habitable again,  someone has to come up with a sure fire way to heat up the core of Mars and  somehow get volcanic activity  going again.  Because  an active core means an active magnetic field which in turn mean there wil be no solar winds to strip  away any atmosphere you might put around the planet.  Next problem , you need to find a proper moon for Mars and one proportionate  to the size of the planet ( those two dinky little so called moons have to go)  Maybe one of  the giant planets  in the solar  system could spare Mars one of their moons ?  Of course this  brings up the logistics how to drag a moon  all the way to Mars and put it into proper balances orbit? _Hm, Ill have give that last one some more thought.  _As to getting water onto the surface of Mars. Well, compared  to the Herculean task of making the planet livable. The solution to this one is easy by comparison . Some person way more brilliant and more imaginative them  me will need to find a way to  divert ice comets at Mars   so that they  will crash on the surface and give Mars all the water it needs.


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## Venusian Broon (Jul 28, 2018)

BAYLOR said:


> To make Mars habitable again,  someone has to come up with a sure fire way to heat up the core of Mars and  somehow get volcanic activity  going again.  Because  an active core means an active magnetic field which in turn mean there wil be no solar winds to strip  away any atmosphere you might put around the planet.  Next problem , you need to find a proper moon for Mars and one proportionate  to the size of the planet ( those two dinky little so called moons have to go)  Maybe one of  the giant planets  in the solar  system could spare Mars one of their moons ?  Of course this  brings up the logistics how to drag a moon  all the way to Mars and put it into proper balances orbit? _Hm, Ill have give that last one some more thought.  _As to getting water onto the surface of Mars. Well, compared  to the Herculean task of making the planet livable. The solution to this one is easy by comparison . Some person way more brilliant and more imaginative them  me will need to find a way to  divert ice comets at Mars   so that they  will crash on the surface and give Mars all the water it needs.




1) I've just seen an article where someone is arguing that it would be easier to put a big magnetic 'generator' - think of it as a shield - on the Lagrange point between Mars and the Sun. This would intercept and shield the main problem - the solar wind. Honestly, this idea is still science fiction, as the generator would be likely be huge and require masses of energy, but probably, by many orders of magnitude more doable than fiddling about with the core of a planet.. (And I point out, we still don't really know how the Earth generates it's field, so there's that.)

2) Why do you need a proper moon? A while back it was thought that something like the moon, in the Earth-moon system, provided a degree of stability that stopped far too much variability, i.e. keeping the axis of rotation fairly 'tight'...however that study was done a long time ago with a pretty simple model, and other studies and research has shown that actually it doesn't require much for a planet to be 'bound' to a fairly restrictive range of variability. In the case of the solar system this means that the orbit of Jupiter is the biggest timepiece that regulates many things...

3) We are finding out that there is a lot more water on Mars that we used to think. We don't need to divert huge amounts of ice comets to the place. Just warming it up will do some amazing stuff. Still, this level of terraforming is in the realms of SF


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## Onyx (Jul 28, 2018)

Venusian Broon said:


> 1) I've just seen an article where someone is arguing that it would be easier to put a big magnetic 'generator' - think of it as a shield - on the Lagrange point between Mars and the Sun. This would intercept and shield the main problem - the solar wind.


Is solar wind the main problem? 



> The greatest threat to astronauts en route to Mars is galactic cosmic rays--or "GCRs" for short.


NASA -  Can People Go to Mars?



Venusian Broon said:


> Why do you need a proper moon?


Not for anything I can think of.


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## Robert Zwilling (Jul 29, 2018)

Does anyone think the next generation of space vehicles will be large robust vehicles capable of lifting off from Earth or is it going to be lightweight utility craft that are assembled in space. Maybe the equivalent of tug boats.

The first time around it was just people thinking of how to get to the Moon, which didn't take all that long. There was no real follow up because there was no followup in the building of a space fleet to manage everything that comes after the landings were made. Everything was just left there on the surface after it was over, with no plans of having anything left behind to function as remote sensing stations. It was just a three day trip.

Would it be easier to maintain an orbiting space station as a shelter/work station or would a permanent installation on solid ground be more practical.

Seeing as how people think they can get to the Moon or even Mars in the next 10 years, when they manage to do it, after landing, what would they be using for shelter? From a practical point of view would a fleet of vehicles first have to go at the same time to carry everything needed. The starting vehicles would be small in size to get off Earth. Perhaps a bigger, simple cargo type ship without an atmosphere could be put together outside of Earth's gravity to carry equipment and supplies to the Moon. It would be easy to accelerate by having another vehicle pushing it. There could only be a few people involved to start with because of the lack of suitable shelter upon arrival.

Once on the Moon or Mars, would the best bet be to use existing vehicles as temporary shelter or does the shelter need such things as thick shielding which would be added after landing to minimize damage from a rough landing. The simple cargo carrier would be the equivalent of a semi trailer that is pulled by the tractor unit. Pushing seems like it would be easier. Adding the shielding after landing seems like it would also be easier to minimize the physical damage from the landing.  Buildings with multiple air locks or dust rooms (mud rooms) would be needed to minimize the damage from the dust. This probably wouldn't be possible on the current vehicle designs due to size constrictions. I'm thinking this stuff would have to be cheap construction, I can't see anyone building an expensive space shuttle and then leaving it on the surface of the moon as a quick fix housing solution. But maybe they will.

Living underground has its advantages. Bigger shelter areas, isolated entry/exit rooms to keep the dust out. The shielding would be achieved by the depth underground the structure was placed. The problem with this scenario is the equipment needed to dig underground, and it would have to be going into solid rock. How hard would it be to get tunneling equipment to the Moon. Would that situation force the use of semi-permanent temporary surface shelters to start with because of the difficulty of transporting tunneling equipment that would be capable of creating instant shelters. Would smaller excavation units be used first by people living in surface shelters. Their motto could be we built this city out of rocks which kept rolling away.


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## Onyx (Jul 29, 2018)

Robert Zwilling said:


> Does anyone think the next generation of space vehicles will be large robust vehicles capable of lifting off from Earth or is it going to be lightweight utility craft that are assembled in space.


I'd like to think that dedicated space vehicles are much more useful than atmospheric craft. And the most efficient current engine ideas for deep space don't produce the thrust necessary to leave the Earth.



Robert Zwilling said:


> Everything was just left there on the surface after it was over, with no plans of having anything left behind to function as remote sensing stations.


What would the sensing stations be looking for, and how sophisticated could they have been in 1972 AND fit in the landers? The moon has no weather or techtonics - we can see it really well from here.



Robert Zwilling said:


> Would it be easier to maintain an orbiting space station as a shelter/work station or would a permanent installation on solid ground be more practical.


The only orbit that is safe from radiation is near earth orbit. Anytime you are sitting on the surface of something your cosmic ray exposure is at least half because the ground is shielding you from below. A crater is better than that, then a chasm and finally a cave.



Robert Zwilling said:


> Once on the Moon or Mars, would the best bet be to use existing vehicles as temporary shelter or does the shelter need such things as thick shielding which would be added after landing to minimize damage from a rough landing.


I would imagine that if the trip to wherever is mass limited, the vehicles are likely to little more than origami. But if you did have the option of combining the base with a large vehicle with full shielding, that would allow mobility with the least risk. I think such vehicles would be short, wide and tall with self leveling chassis so they can go more places. Long, narrow vehicles are great for roads and wind resistance, neither being much of a factor on the moon or Mars. 

Alternately, the base craft could fly where the gravity is low - especially if local frozen water or gas are available to use as propellant.




Robert Zwilling said:


> The shielding would be achieved by the depth underground the structure was placed. The problem with this scenario is the equipment needed to dig underground, and it would have to be going into solid rock.


As I mentioned earlier. the moon has relatively accessible lava tubes that could be used as shelter. An oversized "inner tube" would be required to make it air tight, and that would provide structure, radiation protection and possibly even parking and service area for rovers and shuttles.

But you don't need to tunnel. Mars and the moon have a lot of dust and sand, so inflatable or other semi-rigid structures could just be buried using the equivalent of a snowblower. Add CO2 or water vapor if you want the final product to be structural.


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## Onyx (Jul 29, 2018)

Another possibility for building materials is moon dust or sand packed into molds and heated until the grains fuse, like metal injection molding is done. You'd bake the wall section in the equivalent of a huge solar oven. With a large mirror array and vacuum, heating the material would not be much of a problem; cooling might be, though.


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## Vertigo (Jul 29, 2018)

Onyx said:


> Is solar wind the main problem?
> 
> 
> NASA -  Can People Go to Mars?
> ...


That articles is only putting cosmic rays forward as a problem during the voyage between Earth and Mars and the relevant post was only concerned with radiation on Mars itself. Now I'm not denying that radiation protection will be necessary on the surface of Mars, of course it will and I've always considered it the greatest problem to any kind of habitation there. However regarding Galactic Cosmic Rays (GCRs) NASA seem to be focused on the voyage rather Mars itself and there they have some intriguing ideas up their sleeves:
How to Protect Astronauts from Space Radiation on Mars


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## Onyx (Jul 29, 2018)

Vertigo said:


> That articles is only putting cosmic rays forward as a problem during the voyage between Earth and Mars and the relevant post was only concerned with radiation on Mars itself. Now I'm not denying that radiation protection will be necessary on the surface of Mars, of course it will and I've always considered it the greatest problem to any kind of habitation there. However regarding Galactic Cosmic Rays (GCRs) NASA seem to be focused on the voyage rather Mars itself and there they have some intriguing ideas up their sleeves:
> How to Protect Astronauts from Space Radiation on Mars


I realize what the article is about, but the point the article makes is that both Galactic and Solar cosmic rays are dangerous. And the point I made is that building a lagrange magnetic shield against just Solar cosmic rays isn't going to shield those on the surface of Mars from Galactic cosmic rays.

What will shield people on Mars from both kinds are thick building materials, since there is no magnetosphere or real atmosphere. So given the need for GCR shielding that would also block SCR, why would anyone construct a huge magnetic shield for just the SCR when it doesn't solve the radiation problem?

I just don't understand the point of the lagrange shield you mentioned since it doesn't make anything safe on Mars. It's like an umbrella with a big hole.


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## Justin Swanton (Jul 29, 2018)

I suspect that if NASA gets the funding to keep people on Mars for long periods of time then it needs to find a few good caves. That's the cheapest (i.e. cost-free) way of getting the protection you need. The thing is to find the caves and that's what rovers are for.

To misquote Genesis: from the cave you emerged and to the cave you will return.


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## BAYLOR (Jul 29, 2018)

Justin Swanton said:


> I suspect that if NASA gets the funding to keep people on Mars for long periods of time then it needs to find a few good caves. That's the cheapest (i.e. cost-free) way of getting the protection you need. The thing is to find the caves and that's what rovers are for.
> 
> To misquote Genesis: from the cave you emerged and to the cave you will return.



Sustainability of colony . That's where it gets complicated and costly.


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## Onyx (Jul 29, 2018)

Justin Swanton said:


> I suspect that if NASA gets the funding to keep people on Mars for long periods of time then it needs to find a few good caves. That's the cheapest (i.e. cost-free) way of getting the protection you need. The thing is to find the caves and that's what rovers are for.
> 
> To misquote Genesis: from the cave you emerged and to the cave you will return.


I would think there are better ways using ground penetrating radar satellites of finding caves than driving rovers around.

But I would be unsurprised if Mars' lack of recent volcanic activity and four billion years of sandstorms has filled, buried or collapsed the sort of lava tubes that are the only real way of a having a cave in a place with no flowing water.


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## Vertigo (Jul 29, 2018)

Except of course that all the indications are that it did have flowing water and for quite a long time.

Another approach is to go into some of the canyons which will limit the exposure to immediately above you.


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## BAYLOR (Jul 29, 2018)

Vertigo said:


> Except of course that all the indications are that it did have flowing water and for quite a long time.
> 
> Another approach is to go into some of the canyons which will limit the exposure to immediately above you.



Oceans. lakes and rivers . Lost about 2 Billion years ago.


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## Onyx (Jul 29, 2018)

Vertigo said:


> Except of course that all the indications are that it did have flowing water and for quite a long time.
> 
> Another approach is to go into some of the canyons which will limit the exposure to immediately above you.


Mars had a huge ocean at one time. But I had thought that there hasn't been significant running water near the surface for over a very long time, while their had been forces that destroy or bury caves during the same period.

When was the last heavy flowing water on Mars?


My overwhelming impression of Mars is a place that has its surface shaped by the movement of sand over a very long period. I wouldn't expect to find any particularly concave feature that hasn't been either filled it or worn down, including steep sided canyons. Caves and canyons are formed by things like fast moving water, earthquakes and lava. Mars is mostly wind erosion and the slow flow of sand, brine and dry ice.


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## Onyx (Jul 29, 2018)

Looks like I was wrong about the Galactic Cosmic Rays on Mars:


> "From MSL RAD measurements, ionizing radiation from galactic cosmic rays (GCRs) at Mars is so low as to be negligible. Intermittent solar proton events (SPEs) can increase the atmospheric ionization down to ground level and increase the total dose, but these events are sporadic and last at most a few (2–5) days. These facts are not used to distinguish Special Regions on Mars." (A "Special Region" is a region where Earth life could potentially survive.)


Water on Mars - Wikipedia

I don't know what the mechanism is, but maybe there is just enough atmosphere to make a difference, making SCR protection more important.


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## Robert Zwilling (Jul 29, 2018)

I never thought about the irony of going back to cave dwelling while utilizing the latest technology to stay alive. Spraying foam insulation inside an existing cave seems like a pretty low tech way of creating a large living space. The main things to bring would be prefabricated doors, equipment to maintain and recycle the enclosed environment, and a good entertainment theater.  That would make people think settling on the Moon wouldn't seem too difficult.


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## Justin Swanton (Jul 29, 2018)

Onyx said:


> Looks like I was wrong about the Galactic Cosmic Rays on Mars:.



The amount of Cosmic radiation that reaches the Martian surfaces varies quite a bit but on average it is 300 mSv a day, the equivalent of 24 CAT scans. Of a crowd of people subjected to a little over ten times this amount of radiation - the amount absorbed in less than two weeks - half will die in 60 days. Mark Watney did not have a snowball's chance of surviving on Mars. Neither did the rest of the crew come to think of it.


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## Brian G Turner (Jul 29, 2018)

In the Discovery Channel's series _How the Universe Works_ they mentioned using existing lava tubes on Mars as a possibility for habitation, to escape dangerous radiation.


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## Onyx (Jul 29, 2018)

Justin Swanton said:


> The amount of Cosmic radiation that reaches the Martian surfaces varies quite a bit but on average it is 300 mSv a day, the equivalent of 24 CAT scans. Of a crowd of people subjected to a little over ten times this amount of radiation - the amount absorbed in less than two weeks - half will die in 60 days. Mark Watney did not have a snowball's chance of surviving on Mars. Neither did the rest of the crew come to think of it.


Is that GCR specifically or the sum of GCR and SCR? If it is mainly from SCR than the lagrange magnetic shield could work.


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## Onyx (Jul 29, 2018)

Brian G Turner said:


> In the Discovery Channel's series _How the Universe Works_ they mentioned using existing lava tubes on Mars as a possibility for habitation, to escape dangerous radiation.


Did they make it sound like these tubes are empty and open to the surface where a lightly equipped ship's crew could get at them? Or were they talking about a large effort using excavating machines to bore down to them or clean them out?

I'm sure all sorts of geological formations might be present on Mars, I just doubt many are easily accessible from the surface because of the amount of time the surface has been eroding.


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## Robert Zwilling (Jul 30, 2018)

Looked up lunar lava tubes. Article in Space, based on Lunar Reconnaissance Orbiter images in Jan, used the SETI Institute interpretation that says the lava tubes might be filled with frozen water and come right up to the surface. The article talked about leaving the water in the lava tubes as storage containers for ice. On Mars, it said the lava tubes could provide a warmer and wetter environment to live in. 

Article in Smithsonian Air and Space said LOR images wrong kind of geology for lava tubes in the Philolaus crater. Seemed like they were saying there wouldn't lava tubes in any craters. Any ice exposed ice deposits would be small pits, a few meters in diameter. They were of the impression that hauling a nuclear reactor to the Moon would be the best bet for a suitable power source at locations away from the poles. However, they also said a suitable nuclear reactor would not be built for several decades. Their recommendation was to erect simple shelters at the bottom of polar craters and bury them with moon rubble. There would be plenty of easily accessible water and solar energy at the poles.


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## Onyx (Jul 30, 2018)

Robert Zwilling said:


> There would be plenty of easily accessible water and solar energy at the poles.


They could also put the solar satellites in orbit using microwave downlinks for when the surface is in darkness. But there's no strong reason not to settlements at the poles.


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## Danny McG (Jul 30, 2018)

I dunno why there's so much fuss over a liddle pool of water, everybody knows Mars has got canals full of the stuff


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## Justin Swanton (Jul 30, 2018)

How much would it cost to set up a permanent moonbase? Optimistic estimates put it at US$40 billion or less but I don't buy that. A good yardstick is the ISS. It cost US$150 billion to construct and costs a little under US$3 billion a year to maintain, which includes getting crews to and from it. It will probably be necessary to double or triple those figures for the moon:

1. All lunar structures will need adequate shielding from Solar and Cosmic radiation. To build a shelter using lunar regolith or convert a cave will require fairly hefty construction machinery - you can't do it with a robotic trowel - and everything for the moonbase has to be landed by rocket power on the moon, not just boosted into LEO from Earth.

2. Crewing the moonbase will be much more expensive than the ISS as you have to get the crews to the moon, land them on the moon, and get them off the moon when it's time to go home. That's all additional rocket power, more weight, more cost to get into space.

3. Supplying the lunar base will be more expensive than the ISS for the same reasons.

Let's say a conservative US$300 billion to set up a base that can house as many crew as the ISS - 6 astronauts tops - and US$6-10 billion p/a to maintain it. $300 billion is nearly 10% of the US annual Federal budget. Does the United States have the political will to pay this tab?


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## BAYLOR (Jul 30, 2018)

Justin Swanton said:


> How much would it cost to set up a permanent moonbase? Optimistic estimates put it at US$40 billion or less but I don't buy that. A good yardstick is the ISS. It cost US$150 billion to construct and costs a little under US$3 billion a year to maintain, which includes getting crews to and from it. It will probably be necessary to double or triple those figures for the moon:
> 
> 1. All lunar structures will need adequate shielding from Solar and Cosmic radiation. To build a shelter using lunar regolith or convert a cave will require fairly hefty construction machinery - you can't do it with a robotic trowel - and everything for the moonbase has to be landed by rocket power on the moon, not just boosted into LEO from Earth.
> 
> ...



All of which is a good argument for international cooperation and funding for such a venturer.


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## Onyx (Jul 30, 2018)

Justin Swanton said:


> To build a shelter using lunar regolith or convert a cave will require fairly hefty construction machinery - you can't do it with a robotic trowel - and everything for the moonbase has to be landed by rocket power on the moon, not just boosted into LEO from Earth.


How much conversion does a lunar lava tube require? Some go right to the surface, and the moon doesn't have sandstorms. It seems like that requires some ramps/ladders and a tent.

With more space, some gravity and much better radiation protection, crews could volunteer to stay for years at a time.

And a mass driver could also be used to land supply ships, so you don't necessarily need rocket propellant to land.


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## Brian G Turner (Jul 30, 2018)

Onyx said:


> How much conversion does a lunar lava tube require?



Once you get Health & Safety and government lawyers involved? I'd say a lot. 



Onyx said:


> Some go right to the surface, and the moon doesn't have sandstorms. It seems like that requires some ramps/ladders and a tent.



I presume you're not seriously suggesting the next Moonbase would be little more than a few tents? 



Onyx said:


> With more space, some gravity and much better radiation protection, crews could volunteer to stay for years at a time.



In other words - if the Moon wasn't anything like the Moon and more like Earth? 



Onyx said:


> And a mass driver could also be used to land supply ships, so you don't necessarily need rocket propellant to land.



You're going to need something to control any landing, though. I'm curious, though - do you see mass drivers as replacing launch vehicles to the ISS?


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## Vertigo (Jul 30, 2018)

Onyx said:


> And a mass driver could also be used to land supply ships, so you don't necessarily need rocket propellant to land.


As far as I'm aware mass drivers could be used for launches but not for landings.


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## Onyx (Jul 30, 2018)

Brian G Turner said:


> I presume you're not seriously suggesting the next Moonbase would be little more than a few tents?


As I mentioned earlier, if you already have a structure (lava tube) that provides radiation protection and some insulation, the main thing you need to convert that space to a habitat is to make it airtight and regulate the temperature. Call it a "tent", inner tube, airtight lining, whatever you want. But nature already provided walls, ceiling and floor.



Brian G Turner said:


> In other words - if the Moon wasn't anything like the Moon and more like Earth?


Since the comparison is between the moon and ISS, I'd say a lava tube on the moon is considerably more like the earth than ISS is. Gravity, fewer space restrictions, more radiation protection, etc. So astronauts may be physically and mentally better able to withstand life there from much longer periods than the cramped zero G, higher radiation ISS environment.

And thinking more about the gravity problem, a simple way to "train" while living on the moon is to wear an enormously heavy vest to load the muscles and skeleton like they would be on earth. A 200kg led vest would make it feel like you were standing in earth gravity.



Brian G Turner said:


> You're going to need something to control any landing, though. I'm curious, though - do you see mass drivers as replacing launch vehicles to the ISS?


Not unless the earth suddenly loses the 100km of atmosphere that any sort of ballistic launch system would have to contend with, or the gravitational pull of the earth dropped to something lower than the moon's:

"Mass driver" is a term for a ballistic launch device, usually one that works magnetically, but it could also be something like a cannon. For a mass driver to work on earth with no atmosphere, the launch velocity would have to be mach 33. With an atmosphere it would have to be mach 33 plus whatever extra velocity is required to make up for the velocity loss due to air drag, which is considerable at mach 33.

And just to make this obvious - mach 33, or thirty three times the speed of sound - is not a speed that anything we could make could withstand the air friction. It would simply burn up as soon as it exited the evacuated barrel of the driver.

In contrast, the moon has 1/6 earth gravity and no atmosphere. So its escape velocity is only mach 7, or 8568 kph. Which isn't really much of a problem when you don't have an atmosphere.

If you wanted to build a mass driver that would accelerate a manned capsule up to lunar escape velocity at no more than 9Gs, it would have to 32 kilometers long. But if you planned to use any fuel, then whatever velocity the driver gave you would add to the stored delta vee in the rocket fuel. Or you could use a shorter, higher G driver and put the passengers in a water bath to mitigate the acceleration. Of course, a US Air Force officer once endured 46 Gs for a few seconds without being buoyant.


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## Onyx (Jul 30, 2018)

Vertigo said:


> As far as I'm aware mass drivers could be used for launches but not for landings.


You would need to have a landing craft that would strip velocity off fired slugs magnetically to scrub its inbound velocity. Once its velocity is low enough, the driver could toss it a locally made landing booster (aluminum and oxygen motor).

Or, the incoming ship simply falls into the barrel of the gun and decelerates in the opposite way of the launches.


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## Vertigo (Jul 30, 2018)

Onyx said:


> You would need to have a landing craft that would strip velocity off fired slugs magnetically to scrub its inbound velocity. Once its velocity is low enough, the driver could toss it a locally made landing booster (aluminum and oxygen motor).
> 
> Or, the incoming ship simply falls into the barrel of the gun and decelerates in the opposite way of the launches.


Sorry I don't really see either of those as practical. For the first part you'd have had to lift all of those slugs in the first place in order to throw them away later, and capturing them for reuse would use as much fuel as you saved in the first place. Fuel seems simpler and more effective.

For the second considering the speeds that would be involved the slightest fault/wobble/misjudgement in the system and you have a major disaster on your hands.


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## Onyx (Jul 30, 2018)

Vertigo said:


> For the first part you'd have had to lift all of those slugs in the first place in order to throw them away later, and capturing them for reuse would use as much fuel as you saved in the first place. Fuel seems simpler and more effective.


You could manufacture the slugs on the moon. They don't have to be iron - you could induce a magnetic field in aluminum wiring wrapped around moon rock. If they are fired at just over escape velocity, they will fall back to the moon once a significant amount of their velocity has been transferred to the incoming ship. Or, they can cargo bound for somewhere else.




Vertigo said:


> For the second considering the speeds that would be involved the slightest fault/wobble/misjudgement in the system and you have a major disaster on your hands.


That really just sounds like a lack of faith in technology. There are no crosswinds in space. If the ship is aligned 10,000 kilometers out will remain aligned from there on. Aligning the ship and the open magnetic driver lattice isn't any more difficult than aligning the docking rings on 1970s spacecraft.

Also, the mass driver doesn't have to be a tightly fitted barrel. It will take more electricity, but it could be much larger in inner diameter than the incoming ship. And the magnetic system of the driver would pull against the ship asymmetrically as needed to keep it aligned with the curvature of the moon's surface. If there was a failure the lattice could pop open and the ship would continue in a straight line away from the moon's surface.

A lot of things that seem difficult become simpler when you aren't dealing with atmospheres. You could orbit a satellite a few inches above the highest point on the moons equator if you wanted to. With the right sort of pre-planning a regular system of rising and falling masses around the moon could allow a lot of things to happen without more than steering propellant.


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## Brian G Turner (Jul 30, 2018)

Onyx said:


> That really just sounds like a lack of faith in technology.



Sounds like realism to me.


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## Robert Zwilling (Jul 30, 2018)

If people go to the Moon with the idea that they will be staying there for a long time to cut down on costs, that would put a lot of pressure on the infrastructure to immediately perform as planned. 

Can the effects of low gravity be offset by working out in a gym 2 hours a day. If the floors were magnetic, would walking around in magnetic boots provide a good workout? 

If geological features could be sealed up cheaply, that  could offer some savings on the cost. Seems like the Mayflower experience could be up for a reboot. Ironically in the land of plenty, the Mayflower colonists couldn't find anything to put on the return ship trips, they were too busy trying to survive. If you spend over 60 percent of your time trying to survive I don't think you can get much accomplished. Besides low gravity manufactured products are there any known items that could be brought back from the Moon to help offset the costs? Could there be gem pockets on the Moon worth enough to spend time looking for them.


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## Onyx (Jul 30, 2018)

Brian G Turner said:


> Sounds like realism to me.


Landing a rocket on earth vertically takes much greater precision and control than getting two inert bodies in space to line up with each other. But no one is claiming that SpaceX's vertical landing rockets are doomed. A Patriot missile is working much harder when it cuts through the cockpit of an evading fighter jet at mach 4, and they do that very reliably. 

At some point we're going to have to do this sort of trick fairly often if we want to move things around the solar system without constantly mining everything for propellant.


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## Onyx (Jul 30, 2018)

Robert Zwilling said:


> If the floors were magnetic, would walking around in magnetic boots provide a good workout?


Not really, they would just get a little workout from pulling their feet free. But putting weight on their shoulders would work their body from neck to feet. 



Robert Zwilling said:


> If you spend over 60 percent of your time trying to survive I don't think you can get much accomplished. Besides low gravity manufactured products are there any known items that could be brought back from the Moon to help offset the costs? Could there be gem pockets on the Moon worth enough to spend time looking for them.


No one on the moon is going to be spending all their time learning to hunt turkey and deer. There would be a struggle to get the aquaculture or whatever kind of farming set up, but the main occupation would be assembling automated refineries to extract aluminum, silicon, oxygen and iron out of the soil, plus water ice and smaller amounts of CO2, methane and ammonia. All of that would be useful for the construction of near earth space stations and ships to go to other places in the solar system.

There has long been an assumption that the best way of getting large projects done in space is by capturing an asteroid to mine. But the moon is a big mineable asteroid we already have, and it looks like it has some structures built in that would make it easier to get labor in place than anywhere else in the solar system.


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## Brian G Turner (Jul 30, 2018)

Onyx said:


> Landing a rocket on earth vertically takes much greater precision and control than getting two inert bodies in space to line up with each other. But no one is claiming that SpaceX's vertical landing rockets are doomed.



I'd love to share your optimism that just because the Moon is a less complicated place to launch from means accidents are less likely - but that doesn't make the process necessarily safe, especially considering that even modern rocket launches are prone to fail explosively: Rocket developed by Japan startup in flames after liftoff

Even the robust Ariane 5 rocket has a 5% failure rate: Ariane 5 - Wikipedia

Setting up all the necessary equipment on the Moon is bound to be challenging at the best of times, and any system that might be completed may introduces its own degrees of error. 



Onyx said:


> And thinking more about the gravity problem, a simple way to "train" while living on the moon is to wear an enormously heavy vest to load the muscles and skeleton like they would be on earth. A 200kg led vest would make it feel like you were standing in earth gravity.



That wouldn't negate the problems of weightlessness on human biology, though. I linked through to a good piece on space surgery than ran through some of the problems - it's not just about muscle wastage and bone loss: https://onlinelibrary.wiley.com/doi/full/10.1002/bjs.10908

In the meantime, I think we were discussing water on Mars.


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## Onyx (Jul 30, 2018)

Brian G Turner said:


> I'd love to share your optimism that just because the Moon is a less complicated place to launch from means accidents are less likely - but that doesn't make the process necessarily safe, especially considering that even modern rocket launches are prone to fail explosively: Rocket developed by Japan startup in flames after liftoff
> 
> Even the robust Ariane 5 rocket has a 5% failure rate: Ariane 5 - Wikipedia
> 
> ...


Moon gravity and Mars gravity isn't microgravity. We don't really know how little gravity it takes to maintain healthy fluid distribution in the body. Is 1/6 too little by 1/3 enough?

But the mass catcher I was talking about isn't a rocket and wouldn't suffer the kind of failures chemical rocket motors can. It is more analogous to getting a bearingless electric motor to work correctly - it is a control problem. Just because the closure rate is high that doesn't mean that the degree of control isn't also high while the factors causing error are relatively few. Space is a very controlled environment - the Russians figured out how to place a small satellite in a stable orbit for 3 months using an ICBM in the 1950s. Putting a missile through a hoop on the moon with no atmosphere and multiple ways of checking and controlling alignment should be a relatively simple task - little different than a laser guided bomb.

Sorry about Martian water.


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## Brian G Turner (Jul 31, 2018)

And on-topic about terraforming Mars - apparently there's not enough CO2 to make that possible at the moment: Terraforming Mars might be impossible due to a lack of carbon dioxide



> Right now Mars has an atmospheric pressure of about six millibars – tiny compared to the one bar at sea level on Earth. ...  At one bar, the temperature would be just above 0°C, allowing liquid water, and thus life, on the surface.
> 
> ...
> 
> But Jakosky and Edwards found that there’s probably only enough carbon dioxide in the Martian polar ice caps, dust and rocks to raise the pressure to 20 millibars at most. So we can’t terraform Mars with existing technology, because there simply isn’t enough carbon dioxide. “It’s not that terraforming itself isn’t possible, it’s just that it’s not as easy as some people are currently saying,” says Jakosky. “We can’t just explode a few nukes over the ice caps.”


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## Robert Zwilling (Jul 31, 2018)

Still off course here, since there isn't enough carbon dioxide on Mars, would carbon be valuable enough to make  it practical to export carbon from Earth? If it was exported what would be the best form of it. There is carbon in asteroids but anything of size are few and far between. Would there be more value in collecting the dust than the same effort expended flying around to gather up asteroids of any size?


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## Robert Zwilling (Oct 22, 2018)

Underground water deposits on Mars could contain contain oxygen

Underground Martian water deposits might have plenty of oxygen in them.
Microbial life on Mars is back on the front pages again. It is surmised it would be under the surface where it would be protected and it's resources would also be protected by a thick covering of the upper surface. There could be a reservoir of readily accessible oxygen for microbial life dissolved in a brine solution. I think more likely what is growing under the surface is microbial but not necessarily oxygen based. The physical components of microbial life works in a way similar to mechanical fashion and can use different fuels to to achieve the same results. There is plenty of stuff here on Earth that isn't oxygen or sunlight based and survives perfectly fine. They are called extremophiles, meaning living in extreme conditions compared to normal Earth life. It wouldn't be unlikely if oxygen based life was the extremophile life for for the rest of the solar system, or even the galaxy, and all the stuff we call extreme is the majority format for life in general.

Life on Mars, having evolved under such conditions and knowing that there are organisms that can "eat" metal and plastic on Earth, it might not be unlikely that spacesuits would be on the Martian microbes menus as a tasty after dinner treat.


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## BAYLOR (Oct 22, 2018)

Robert Zwilling said:


> Underground water deposits on Mars could contain contain oxygen
> 
> Underground Martian water deposits might have plenty of oxygen in them.
> Microbial life on Mars is back on the front pages again. It is surmised it would be under the surface where it would be protected and it's resources would also be protected by a thick covering of the upper surface. There could be a reservoir of readily accessible oxygen for microbial life dissolved in a brine solution. I think more likely what is growing under the surface is microbial but not necessarily oxygen based. The physical components of microbial life works in a way similar to mechanical fashion and can use different fuels to to achieve the same results. There is plenty of stuff here on Earth that isn't oxygen or sunlight based and survives perfectly fine. They are called extremophiles, meaning living in extreme conditions compared to normal Earth life. It wouldn't be unlikely if oxygen based life was the extremophile life for for the rest of the solar system, or even the galaxy, and all the stuff we call extreme is the majority format for life in general.
> ...



Life has a tendency to find a way to survive in harsh conditions.


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## Robert Zwilling (Oct 23, 2018)

I always think of Jurassic Park when Life has a tendency to survive in harsh conditions.


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