New Mars Forums

You can look at a map of the globe of the Earth, and see patterns.
In todays world, most space activity is with Asia.  Little or none with the other parts of the world.  They are sleeping now.  Not so much 500 years ago, it was the reverse.  A beautiful exception seems to be parts of Southern Europe still active when they should have fallen into darkness.  This may be because of the E.U.

As for North America, don't forget that we were Asian-Like before being invaded by so called western peoples with Africans.

Western has multiple definitions however.  Once upon a time when the world was flat (And it was in the human mind, still is in most minds),
the West was the Roman Empire, the East was east>>> of that.  Choose your flavor.

So, the North America you are looking at is currently in the bonds of Roman pretenders, but that will end.  We will find our Asian character again.  If you are wondering, I am not particularly African or Asian.

The point being that their are many America's/North America's.  At the moment because we are wrapped up in NATO due to history, the definition of Western is excessively tilted towards the Club Med faction, when in fact it should be balanced between northern and southern factions. 

America is in cultural wars just now, and that is not due to end for 10 more years.  We currently have a president who has an unusual concept of what we should do.  In a way it was good to have him shake things up, and see what shakes loose.  However, I think it is an aberration and that there is a very good chance that America will emerge with a new perspective, and will no longer be obsessed with protecting the Roman Empire (2000 years ago) from technological Asiatic hordes.

The Russians were our allies in WWII, and few know it, but in the Civil war, (Of America), Russians helped to keep the Europeans from joining the war against the Feds. (Like it or not).

Truth?  Well lets see in 10-20 years if we are still here to see.

OK Tom, your right, I will loosen up on it.  There are too many variables to say just what pattern will turn out to be the best fit.

However, I was trying to emphasize that from the Moon perhaps could come a very large quantity of Oxygen, and that perhaps, that would require a minimum human population to maintain the production and launch system.  In other words the Moon might be the best local area to get mass quantities of Oxygen.  The Linear electromagnetic accelerator and the catcher, whatever their structures might be, will have to actually work though in a practical way.  Lots of needs there.

Here it is again Tom.  Please consider reading it.
http://www.scientificamerican.com/artic … scribe=yes

I recall seeing quotes of a 25% savings of fuel.  It can come with a time price however.  Extra months perhaps in some cases.  However, for sending pre-positioned supplies the time issue may or may not be an issue.  However in one of my previous links, they cited a way, (Which I don't fully comprehend), where in the Martian, the supplies needed could have been sent sooner, significantly sooner than with a hohmann transfer.

Now, I am ignorant.  It will do no good for you to do a can-can't argument with me, because I actually don't know.  I can read however, and the material I am reading seems to indicate that a hohmann transfer is not necessarily the always best method.

Please dispute the links I have posted, and educate me about it if I need a further education.  Really.  I don't know if I am being trolled by Boeing and NASA   Perhaps they have nothing better to do with money than to BS me on this stuff for fun.

Gerard O'Neill also had pellet catchers in "L" locations if I recall.

If asteroid mining will start by bringing back water, I would suppose for large mining efforts eventually they might try to dump the Oxygen, and just bring back the Hydrogen.

And then there is the Moon, which is a big Oxygen tank among other things.

Just maybe you could all have what you said, if there were significant economic activity on the Moon.  I don't see Mass drivers as being worth while to launch humans off of the Moon.  Also, if metals are available from the asteroids for orbital construction, I don't think launching metals off of the Moon is a good plan, with or without Mass Drivers (Linear Accelerators).

But Gerard O'Neill also had pellet catchers in "L" locations if I recall.
and Terraformer said Coil Gun.
and I like Oxygen pellets, I presume that they are paramagnetic.https://www.google.com/search?q=Solid+Oxygen+paramagnetism&biw=1366&bih=673&tbm=isch&tbo=u&source=univ&sa=X&ved=0CCkQsARqFQoTCOSlmp6FtsgCFQTMgAodEM0Bfw
and Tom likes to launch spacecraft with a massive linear accelerator.
and antius likes to shoot objects out of a spaceship to propel it.

So do all of it maybe?

Add electromagnetism to Gerard O'Neill's pellet catcher. 
Also turn it into a Magnetic Plasma Bubble device.

The interior of the catcher must generally be kept below the freezing point of Oxygen?  Or can you hold some Oxygen in place with the plasma bubble?  Even temporarily might be enough if you eventually condense the gas inside the catcher.

So Terraformer is pushing pellets at the pellet catcher, but they might evaporate in the sunlight?  You might still catch the gas if it sticks together with magnetism.  I don't know if it would.  Anyway, perhaps the pellets need a minimal coating, to reflect sunlight, and to allow the interiors of the pellets to self pressurize.  That would be another method.  Another method would be to only shoot pellets when the Moon or Earth were blocking the sunlight.  Anyway...

If I recall the Gerard O'Neill concept of the collector, the pellets would slow down while climbing up the Moons gravity well, and would not impact at a very high speed.

They should shatter, and perhaps even partially vaporize and that vapor expand and rapidly cool, its heat radiated away.  The cup or cone shaped container, which would also be magnetic with one open end, might be able to retain much of the Oxygen.

Then if you have a spaceship to launch, you load it up with Oxygen as mass to propel it, (Per Antius), and then you might even give the ship a boost on it's way out, using Toms method, (Using the electro magnetism of the collector in a different way for the launch.

And the Oxygen liberated from lunar soil, leaving behind building materials on the Moon to build things on the Moons surface.

A variant of this plan would have a collector in low lunar orbit, Coil guns shooting Oxygen into the collector "Cup" from many locations on the Moon.  The collector cup maintaining orbit by the impacts, and also it can have it's own propulsion, where perhaps it also shoots out Oxygen.

Low Lunar Orbit:
http://science.nasa.gov/science-news/sc … _loworbit/
This would help in the case where you don't want your Oxygen pellets to vaporize, or the vapor to spread too far before impact, but your impacts from sub-orbital pellets might be rather high.

OK, at the end of my last post, I said something about radiation shielding which is not very good I now think.
The point being that if you are going to do a balistic injection into the advancing space-time well of Mars, it would be silly to put a radiation sheild into a circular almost Mars orbit, and to abandon the eliptical radiation shield for it.  Instead you would capture your radiation shield into Mars orbit along with your spacecraft.  The only savings you might have by exchanging shields would be to leave the shield in it's capture orbit, and move the spacecraft to another location of safety.   Most likely I would suppose you would land your humancraft on the ground, and use Mars as radiation shelter.  Other options would be to have some kind of lower orbital sheltering, if you were not going to land.  In that case using a moon for shelter.
Upon desire to return to Earth, the spacecraft would exit the surface of Mars, and re-aquire the radiation shield, and then exit the gravity well of Mars, hopefully to make a pass at Earth allowing a re-entry to Earth.
So, at least I have straitened that out in my head a bit.
Getting back on topic, I noticed that the main ship was rather grand in it's mass and structure.  Good for the imagination, and for the movie, not so practical for money.  However I will attempt to speek of already proposed methods to aid in having those capabilities, and will attempt to add to those capabilities with an item #3 which is included in what follows.
As far as advance supplying of the Mars location, I think the ballistic method is likely to prove great.  Likely to use electric rockets, and for the surface aerobraking, perhaps direct, and perhaps atmospheric grazing methods.  So efficiency is available, at the cost of the use of time consuming and tedious methods.  Likely to be worth the effort however.
1) I have wondered, and have been shot down before on the issue of leveraging the strenth of a electric rocket onto a chemical rocket.
An easy case is where you might send a chemical rocket booster into the orbit of Mars.  Then if it had a use, it would be more effectively prepositioned by the electric rocket than it would be by chemical rockets.  But it would need a use.  I guess the best use would be for a return trip to Earth, but perhaps it could also be a lander.  Can gravitational fly by methods also help?
2) I have wondered, and have been shot down before on the issue of leveraging the strenth of a electric rocket onto a chemical rocket.
A harder case would be to speculate on doing this with a solar orbit, with the intention of helping a mission to Mars.  Sending a chemical booster system into an eliptical orbit with resonance of Earth. 
In fact, if I understand correctly NASA is considering a concept where a radiation shield in a solar orbit could aid a trip to Mars.  If this is true, then such a shield could be moved and postioned into suitable orbits, using both electric rockets and gravitational assists.  If you are going to do that then why not also send other equipment.  a) Addional thrust power (I will not define this to a narrow inetrpretation at this point). b) General supplies (Bulk consumables). c) A centrifuge (Perhaps GWJohnsons baton method).
So, if I was correct and NASA is considering a solar orbit radiation sheild, I presume it will be incorporated into the flight to Mars, along the way, and will be taken into Mars orbit with the spacecraft.  So, this would require a deep space linkup between the Mars craft, and the radiation shield.
So, this suggests to me that there could be three pre-position locations for a Mars mission, that robots would collect materials to.
1) Mars surface. 2) Mars orbit. 3) A prefered eliptical solar orbit.
#3, if it were used would be an orbit which could be reaced relatively easily, which would be convenient for pushing on to Mars when ready to push on, and would offer much in the way of an abort back to Earth, if necessary.
The orbit ideally would offer a realtively "Free return" to the Earths vacinity, if the push to Mars was aborted.  The pre-positioned supplies should be sufficient either to support the effort to go to Mars, and they also should have sufficiency to offer life support and method of return to Earth for the safety of the humans.
So, if #3 were done, it would requre a launch to deep space, to connect with a collection of objects at a particular point in an eliptical orbit.  That eliptical orbit would have a significant part of the energy required to later aquire the solar altitude and space-time position to enter the Martian gravity well using a balistic entry method.  That orbit should also have the correct energy and shape, to make it compatable with most of what is required for a return to Earth abort, (Although that might require a loop around the sun first).
However, I do bend for new technology.  If the VASIMR shows up as practical, then electric rocket leverage rocket methods may not be a preference.

Anyway, there you go, no humans harmed, as this is play time, not an actual mission.

This might not be the direction you wanted but...
http://www.space.com/30749-the-martian- … -mars.html

So, in my own words, I would perhaps have said that this other method/new method, would have the spacecraft enter a trailing orbit of Mars orbit, but then add a bit of speed, and allow/assist the spacecraft to catch up to Mars, using the gravitation of Mars as an assist?  Perhaps I am close.  Of course I have just read this, I am a featherweight as it comes to these matters at least.

Comments on the movie:
I like to see the movie.  Movies have to sell, it is a business. 

I think the movie was at least reasonably brave.  Some movies, about space exaggerate danger, and in fact the moral of those stories is that moving from point A to point B is dangerous, and the best you can hope for is to circle back home, and end up in the primordial mud, run and hide.  Granted, real life sometimes wants that remedy.  Not all brave deeds are wise deeds.  However, since it is not a real space mission, but play acting about a space mission, the emphasis should be on "Play".

In play mammals in particular rehearse what they will do as adults.  Humans even more so.  Children should most likely be allowed to have heroic delusions, up to a point.  Sci-Fi, is part reality, and part fantasy.  One foot on the ground, one flying.

The movie was pretty good that way, and I was happy to see it ended with the notion that there was going to be yet another mission to Mars.

So, seeing that as in the reference I added some other people have additions that could have been made that would change the story, that's all very good.  Playtime, necessary for organisms with a greater mind capacity, the capacity to go beyond the emotions of fear, using problem solving.

At least that's how I see it.

An alternate habitation/terraforming scheme for Mars, based on the contents of the thread.
-First of all habitation and habitat are more important than terraforming, partial or full(good luck).
-Second, consider the atmosphere of Mars to be a conveyor belt for Carbon, first it is a container of Carbon, and when depleted, it will recieve more Carbon from other reservoirs.
    -Polar ice caps
    -Regolith
    -Asteroids
The Carbon is valuable, and is to be joined with Hydrogen from Martian ice, and other substances as well, to produce bulk materials such as plastics.
If a heliostat and tower system becomes the primary solar biosphere for the northern hemisphere, then free Oxygen would be released to the atmsphere.
I am inclined to think that Ozone will have a hard time existing in an atmosphere dominated by CO2, and further it is not compatible with Chlorine, so unless some type if UV resistant organism can be engineered, I don't really see a very big possiblity for an exposed biosphere on Mars unless that is modified.
So, I actually would like to see the Carbon and Chlorine pulled out of the atmosphere.   That would reduce the atmospheric pressure, so it would be good to add CO2 from the polar caps, and Regolith, at a steady pace, while eventually generating a O2 dominated atmosphere with just a pinch of CO2, and as little Chlorine as possible.
Once CO2 was a minor component, it would be necessary to extract CO2 at a greater expense.  One possible method could involve an organism with Hemoglobin, but we already have technologies to extract CO2 anyway.
At that point, I would hope an Ozone layer would occur, and small life might take root on the surface, Lichens, Cyanobacteria, bacteria, Algae, but not in great significance without nurturing.
Even at 6mb pressure, an O2 dominated atmoshere with an Ozone layer on high would have many benefits.  For instance any habitat or space suit with a power supply might be able to draw from it to provide breathing gasses for humans.  Also, the Ozone if not in contact with manufactured materials would help to protect them from deterioration from U.V. light.
I have mentioned a trickle of CO2 still going into the atmosphere.  That would be regulated thermally for the reseroirs of the polar ice caps, and the Regolith.
As for asteroids, the number of suitable asteroids made to encounter the atmosphere would determine that Carbon contribution.
With a trickle of Carbon Dioxide, and the extensive water ice that is now thought may lie below the surface of the northern hemisphere, it is reasonable that from a 6 mb atmosphere pressure, you might hope to rise to a fractional bar atmosphere almost entirely of O2.  That can be modified if a reasonable source of Nitrogen can be obtained to add to the atmosphere.  That is the goal would be an atmosphere humans could breath without a space suit.
At the point where the atmosphere is fully Oxidized for humans, the trickle of CO2 has to be turned off.  That would be done by lowering temperatures, and by of course stopping adding asteroid materials.
Thermal regulation should be possible by regulation of greenhouse gasses in the atmosphere, and also since the northen biosphere would be associated with a massive number of Heliostats, the Heliostats could be used to regulate the refectiveness of the northern hemisphere.
So, it would not be impossible to imagine with the existance of an Ozone layer, placing an artifical soil at locations in the northern hemisphere, that would support tundra or cold tiaga.
Since the Heliostats should be able to fine tune temperature in local areas of the northern hemisphere, for brief periods say a few months above freezing temperatures tollerated, to allow that sort of surface biosphere.
Otherwise, ice covered lakes are not ruled out and of course open water tundra and tiaga permafrost lined ponds.
As for the Southern Hemisphere, I would anticipate that such a Mars would have little trouble having mirrors in orbit that would add heat to the southern hemisphere.  That to create rivers and canals from the south polar ice cap, and to conduct that water to locations of irrigation, and lakes.

Louis said:

Solar then would appear to come in three flavors recognizable now.
1) Solar Photovotaic (Or similar).
2) Solar Thermal.
3) Solar organic.
I have previously focused on ice covered lakes, which could be considered partially 2 & 3.  The notion here was there is so much of Mars that is cold and icy like Antarctica, why not adapt to what it is more compatible to do.  The plan has some merit, and I do not abaondon it, but have always considered that it must come later, if there were any posibility to inhabit the equator effectively.  The limitation on habitation of the equator was a described lack of water there.
So we were left with mining ice, or drilling for aquifers as our methods to obtain water.  Those generally would have required heavy machinery.  Now, if it is possible that small quantities of water are collectible at certain locations around the equator, it is reasonable to think if a dispersed set of starter comunities at the equator, and from there seqwaying towards either or both drilling for aquifers, and adapting to high lattitude habitations utilizing large quantities of ice and water extensively.
I am begininning to think that in fact a likely situation at the equator is that aquifers that were charged thousands/millions of years ago by snowfalls, and ice deposites, may be gradually evaporating, and in the process, of the vapors traveling to the surface, the vapors condensing into ice pockets near the colder surface.  The brines then causing some of it to become visible from orbit.  That is a hope anyway. 
So, if this is true or not, but somehow such small pockets of water are availible, I certainly have to see the logic of starting at the equator.  But I see that as being a very sparse population.  Getting ahold of massive water supplies still will be the big prise.
So, I think a megacity is a good idea after the equatorial sparse population is established.  I was thinking of finding massive ice as close to the equator as possible.  However there is this!  Some of the kids out there have done a good thing.  I think you just hinted about this.
http://www.cnet.com/news/3d-printable-i … e-on-mars/
http://www.marsicehouse.com/introductio … vd8uoqguge
I was thinking of some nasty underground snail shell spiral chambered city, with ice or water for counter pressure.  However the idea in the link, does have greater attractiveness.  I would think that with the 3D printing you also could add a small amount of fibers to the ice, say carbon/plastic? something or other. Anyway, I want a megacity for economic efficiency.  Given that you could have ice covered lakes, ice houses, and ice tunnels, a city can be contemplated.  A massive multipart habitat where the inhabitants will normally not be involved in EVA's on the surface in suits.
Likely they will need Protective gear for construction, and for accessing areas with only partial life support.  Example: for working in very cold ice tunnels, you want arctic clothing, and perhaps if the confined space atmosphere is potentially toxic, you want breathing gear.
I see that if you really wanted to generate large amounts of economic activity a city like this would be suitable.
Per the link, happy circumstances could be available for the inhabitants. 
Connectivity: Ice tunnels like subways would link the various above ground buildings.
Other tunnels would be continuously expanded to provide make up water, and also to provide emergency survival habitat in the event of some above ground habitat problem.  Such a tunnel network would also provide long term storage for food, and fuel, Oxidizer.
Tunnels would also allow for connecting underground mines to this city.  While it will be diffacult to expect high grade ores to be present, they might be.  And for a relatively convenient situation such as the ice city, lower grade ores might be worked with.
But you stressed solar;
Tom, really started some thoughts in my head, when he suggested landing a water tower on Mars, so that people could take showers
It from previous discussions it did occur to me that you could do so.  At the equator and also at the ice city.
So, indeed, build a transparent bubble to grow Spirulina:
https://en.wikipedia.org/wiki/Spirulina … upplement)
Cultivation:
http://www.startupbizhub.com/growing-spirulina.htm

In diluted urine:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1361757/
A nice video:
https://www.youtube.com/watch?v=DfVmsUHJWaw
I guess if you have lots of food and Oxygen you can grow fish. But the settlers can have their choices.

Provide a tower to put your bubble on.  On the equator early towers could involve hills, or piles or rocks.
In the ice city, of course your tower can at least partialy be of ice.
In most locations of Mars, without solar concentration efforts, your bubble of water to grow Spirolina will be subject to freezing.  So when the sun goes down you will have to consider what to do about that.  A larger installation might be fine over a normal night.
Anyway, I am thinking Heliostats.  They would make the difference from having a silly attempt to grow Spirolina in a tower, and having a real potential to have economic gain.
https://en.wikipedia.org/wiki/Heliostat
A picture is worth a thousand words:

So, now you have a machine which can heat the water to temperatures the Spirolina best grows in, and you can incease the photon density inside your window bubble.  So, you potentially have a massive source of Oxygen, and perhaps biofuels, and of course food.
Further, if you build a power generating system into this you can play further games.
-Your power generation system not boiling water but some fluid with a lower vapor pressure.  You heat it is coils inside of your transparent bubble.  You then conduct the heated fluids to a power generating machine (Turbine?).  And of course you may use typical ambient Martian temperatures to provide the means to condense the fluid.
If done correctly then you can cool the waters inside your transparent bubble, and so may focus even more heliostats on the bubble, therefore increasing the photon density.  If you stir the Spriolina, then you can make best use of this photon density, since you would be presenting the organisms to breif intense exposures to photons, and then letting them "Rest" inside the group.  Of course there will be a limit of utility for this.  Spirolina may like lots of light but would not like too much light.  I don't know what the limits would be.  However, of course that can be determined.
So Heliostats would lend themselves to mass production.  Should they malfunction, an robot could move them into a pressurized garage for servicing.
As for the transparent bubble.  I have previously tended to try to use counterpressure measures to interface with the Martian environment.  However in this case, I am thinking tensile strengths, probabbly some type of "Plastic", that is not glass, something of a transparent film.  I think you know what I mean.  Better people than me can effictively figure out what would be best.
By using photon concentration with Heliostats, best economic benefits can be obtained, while minimizing the amount of differential pressure holding window you would have to provide.

Oh, also, of course if you have heated water you can have a method to heat your hab, and also in it's methods provide distilled water.

Louis, I hope you don't mind be posting on this thread.  Let me know if it is a problem for you, no bad feelings if so.
Alright, I pretty much figured this would happen.

http://phys.org/news/2015-10-mars-life- … hreat.html

So, the game is on.  While I support the morality of making stringent efforts to not contaminate Mars with Earth life, if there is a reasonable suspission of indignous life, I also believe that this situation will be used as a political football by entities which might want to exploit it for there purposes.  I believe that it is true that during the settlement of the America's at least one colonizer had a policy as shown here.  "If the natives come to you peacefully, then enslave them.  If they run away then kill them."  I do not believe that this is a current practice that I am aware of in the America's, but I do know that their are many peoples, both in my country, and even more so outside of my country who don't respect the personhood of others.  Some of them do in fact have doctrins that proscribe the formula mentioned above, or at least they are to block us from escape/expansion.  The notion being that we are to be subordinated.
And then again I also think there are always people who want to scrap other peoples projects.  Sort of the strip the copper out of the buildings mentality.  Some people like to make a profit by causing shipwrecks.
So, because I would like the question of life on Mars to be answered as soon as possible, I will attempt to propose a possible method that perhaps wiggles through the barriers reasonable people (Scientists, moralists), and our foes will place in the way.
I propose a multi-robot method.
1) Using catapult and fishing technology (Rod and Reel), I suggest a method to extract samples by forward casting into a presumed habitable area, and to deliver it to another robot by reverse catapulting it away further from the extraction site.  This particular robot, could be highly sterilized since it will have much less sensory devices on it.  How it gets to it's working location is open to options.  I presume several possiblities.
2) A mobile robot will at a distance go an get the samples, and take them away for analysis.  Taking them away might be; a) The lab is on the rover, b) The rover takes the samples to an even more remote lab, c) A sample return to orbit option.
In the process of casting the sinker might be a sample collecting device, or perhaps a cotton swab of some kind would be used, or something else.
The fish line and sample device would have the greatest level of sterilziation, but I assume that that entire casting and catapulting robot will be very sterile.
On Mars inertia is the same but gravity is .38 I believe, and of course air resistance is much smaller than on Earth.  I also presume that the robot that casts and catapults will be really well made, if the study of those technoligies on Earth done correctly.

So, I presume a fairly large set of isolation distances.
 
As for the sample return option, I suggest that that be part of a personed visit to Phobos and/or Demos, to attempt to find samples of rocks, in particular rocks thought to have been ejected from Mars over the history of the existance of those moons.  This of course will lay the groundwork for a future around Mars, with or without the existance of life on Mars.
Such a  set of coordinated methods might meet broad support, but you will never get support from those who's intention is to trip you up.  Some of them might pretend to support you, but of course you will also have to be on gaurd for sabatage.
The entire spectrum of potential human intentions have to be watched and considered.

Of course I am also expecting that more accessible sites of brine hydration will be found to practice this method on if the method proves to be worthwhile.

This is on topic for being a history of underground lakes which once existed on Mars apparently.

http://phys.org/news/2015-09-hypothesis … loods.html

That would have to be some very deep hidden canyons.  Not exactly the same as lake Vostok, and not likely either I think to still have liquid, but maybe.  Who knows.  If the Northern half of the planet is a sediment filled ocean basin, and the sediments are mud and ice mostly, perhaps if it really were an ocean floor, there might be hidden "Undersea" vents in a deep hidden canyon.

Lake Vostok:

https://en.wikipedia.org/wiki/Lake_Vostok

Vostok being glacial, and any canyon lake not quite the same, but perhaps there would be similarities.

One think would be very true, is that if you could find a remnant of such a lake, either with liquid water or totally frozen to the bottom, it is worth investigating if it can provide for needs for humans on Mars.  (And of course scientific data).

You could build very large buildings in it, where you dig down, (And get more water), to build a new floor below.  You could also expand out sideways for more space.  In some ways nature says that a large body is suited to a cold environment.

If radar determined that their was liquid water, then perhaps for science that would be drilled down to.

However to suit the building I suppose you would want a layer of ice ideal for your building.  That is where eventually you reached bedrock.

If you could also reach a suspected ore body by doing that so much the better, but detecting it might be a problem, except for perhaps Iron.

Anyway, someday sometime.  One big giant building/city.  Makeup water provided by expanding into more volume of ice.

Tom,

Our culture has always had a need for "Commons".  Not all property is owned individually.  Nor should it be.  I am very fond of individuality, but it has limits.  Even corporations have common areas for the employees.  For instance not every person has their own private bathroom, but they often have their own individual work spaces, even if temporarily.

I apparently am responsible for indicating that.  It was something I read recently. 

Actually, I have since read, that they could be allowed to send a machine, but the rigors of sterilization would be very very expensive.
Further, our machines would not actually be able to work in the areas where the water is found.  Too hard to land on and too rugged for the rovers.

It may be possible that more accessible water will be found in areas that machines could explore.