New Mars Forums

I'm not against anything that works.  The next unexpected breatkthrough is what will likely get us to a new chance, and I think we can agree that we want that.  Expected breakthroughs, they typically just lead to more chains.

The status quo is death.  I am also skeptical of the cold fusion thread I started, more so than this one, but someday someone is going to find a way, and it won't be a conventional dogma scheme.  1 in 1000 might work, but still, it is important to keep trying.

Thank You,

Rusakof

It is nice to get an answer.

Of course I have made a complex and perhaps unressonalble request, but you gave me part of what I wanted. As did GW. 

Really thanks.

Thanks for the reply on the Nuclear part.

However, given an energy source nuclear or non nuclear, does it make sense that a "Mix" could be useful as a propellant?

One part which expands more with the application of heat, and one part which has greater mass per volume.

The example of water with Hydrogen bubbles in it, becomming water steam at a high temperature, and also Hydrogen which expands more, pushing the water steam to expand more.  I have woried about the Hydrogen becomming disolved into the steam but I believe that at least for liquid water, you can saturate it and then add more.

Obviously if you have water, you can have Hydrogen.  What you do with the excess Oxygen beyond breathing it of couse is another issue.  I have tried to consider if it can provide propulsion by being expelled with a linear accelerator (Magnetic), or if you could inject it into the steam stream as well.  Perhaps not only normal nuclear heating could be applied, but could you also boost the thrust by applying some microwave energy to expand the down stream flow just a bit more at the outlet?

Of course handling plasma might be something you would not want to go to.  Just superheated gasses?

I need some further understanding on the use of nuclear propulsion in space.

Typically I have read that Hydrogen is the prefered propellant, because of it's expansion properties.

I have also seen reference to water as the propellant mass, because it is availble many places in space.

I am wondering about a hybrid.

What might be possible where you would have a pressurized tank, and pumped water into it and also Hydrogen in a compressed gas form.  An agitator would be needed to mix it into a slurry of water and compressed Hydrogen bubbles.

Having that could you heat it in a nuclear propulsion system, and get the advantage of Hydrogens expansion properties, and also the mass of the water?

(I am guessing that cavitation might be a problem with the metal parts).

I am thinking of a bullet.  The rifle recoils when the burning explosion pushes the bullet out of the gun barrel.  So the water is the bullet, but it also vaporizes and expands in the rocket nozzle, and the Hydrogen is an even more expanding gas.

I understand that water could be corrosive, but could the Hydrogen counteract that as well?

Alternately you could push heated steam out of the nozzle, and inject liquid Hydrogen?

I am thinking go with the microbe with the sugar.

An inflated plastic bag on the surface partially filled with water could maintain a relatively gentle habitat for the bacteria, since if there is enough thermal inertia, ice phase can be avoided.  (I would think you would cover these balloons with a UV protective plastic tarp draped over them.

Yeast(O2 + Sugar) = Protein & Alcohol.

Alcohol could likely be feedstock for oil and plastics.

Mushrooms(O2 + Oil & Biowaste) = Certain Nutritions humans can use (Mushrooms can grow in a warm damp cave).

So, you would already have a good start.

After that you would only need a relatively small greenhouse to provide the rest of the needed nutrition.

Of course turning yeast into an appealing food might take some work.

I would start like that, and hope that they also engineer some complex plants for great efficiency.

That's a notion to consider.  Be useful if you can.  That's pretty much the requirement to play ball.

I don't want to interupt your worthwhile conversation, but I have a notion of an item of hardware to propose which might be useful to an interplanetary mission where water is a large source of propulsion mass.

Here is my simple cross section diagram for it:

The notion is to use a "Bigelow Expandable Activity Module, or BEAM" as a rigid container.

http://abcnews.go.com/Technology/inflat … d=18240124

Inside a flexable/foldable/elastic bag filled with air.  Inside of that a pole or a pannel to attach equipment or sleeping persons to.

As the water gets used up as propellant, the area filled by air gets larger.

Upon a refueling, it gets smaller.

I think the circular Bigelow BEAM might be quite good, if it is not too mass heavy.  That is something I do not know.

I do not expect that the travelers will have only this to dwell in, but would have an attached crew compartment.  However for various reasons it might be useful to be able to habitate the air filled volume as well at times.

-Cramped space in a crew module.
-Radiation storm.
-Radiation protection during sleeping.
-Crew module becomes temporarily marginal for habitation.

I have indicated two modes of use, the pure water mode would be where you do not want to monkey with purifying the water in the volume before using it for propulsion.

The other mode would allow you to grow plants in the water if the air bag was transparent.  This would allow you to use LED's mounted on the pole or pannel to illuminate the interior, and that would be to produce Oxygen, purify Urine, and just maybe grow food.  That whole process would be an additional complecation, and would require also that the water be purified, perhaps by distillation before being processed for propellant.

It is worth noting that one of these would be a novelty, but several joined as a unit could be a space station around Mars, and also a propellant depot.

Anyway, it is a direction to consider perhaps.

Those points, and also the two asteroid (NEO) mining organizations.

If the asteroid mining operations work, then it sort of dampens the notion of the Moon for non-Moon resources.

So, the Moon is an object in itself, perhaps a bit like Antarctica, but with space tourism?

I would think that an item of research might be how the human body holds up in the Moons gravity field, so perhaps tourists could get a discount, if they agree to be part of such a study.

That information might give clues on how humans might do in the Martian gravity field.

An interesting notion might be if there may be people who would want to live on the Moon long term, as a sort of home for a awhile.  Artistic type people.

Of couse Scientists would likely have actions such as Telescopes on the far side?  Or would that actually be automation with a few repair people on hand?

Perhaps it is OK, due to the lack of current activity if I should suggest an optional deviation from that plan.

I have considered a "First Step" to neutralize the PH of Venus and make it more machine friendly.

A second step would be to reduce or eliminate the cloud cover, letting a large part of the heat potential out.

Metals inserted into the atmosphere would most likely move the PH towards neutral.  I expect it would take less metals than to dissapear the whole atmosphere into metal compounds.

It might be a perference if the Sulphuric Acid reacting with metals would leave behind some H20, but that may not be a subsidiary feature of such a process.

At any rate if you can dump metals into the atmosphere of Venus, perhaps not just Magnesium, but other metals, and Silicon.

I have speculated on a shell in the atmosphere previously, where below it is the bulk of the CO2, and also >3/4 ths of the Nitrogen.

Above the shell, Nitrogen at 58%, and if obtainable 42% Oxygen.  (500 MB?, about right for Venus with Times 2 sunlight?)

I am aware that Venus has ferocious winds.

However such a shell would "Float" on a layer of mostly CO2 like the surface of a waterbed.  Should it bulge, the weight of the bulge would draw it back down, because the above layer is approximately 1/2 as dense as what is below.  The shell would also need to be lighter than the mix below, which requires hollows with a light gas.

The sequence of building might be:
1) Get rid of the acid PH.
2) Get rid of most of the clouds.
3) Wait for the turbulence from this change to settle down.
4) Floating habitats, and high temperature robots on the surface.
5) Perhaps the Hall weather machine?  Refelctive bots?
6) More cooling if 5 is available.
7) Have a robotic system build a shell,  hives of very small robots. 
8) Begin separating the atmosphere above from that below.
9) Thicken the shell.
10) Habitate the surface of the shell.

It is all far fetched, but not the most far fetched ever mentioned here.

After all that either export atmosphere by some means, or indeed continue to import metals from Mercury, and reduce the volume of the atmosphere.  The falling materials of course would have to be fashioned into shell materials, or pushed under the shell.

If I remember, you like shell worlds also.

I can also say that if this was done, then the "Shell" could generally be highly reflective, and would have only 1/2 bar of atmosphere above it which would help cooling, the lower layers below the shell would eventually cool more.  Of course that would then require that the shell adjust it's size, so it's not all that easy, but I am guessing you are enterained a little bit by my response.

Venus is the really hard one.

Edited 01-Feb-2013 (I don't care much about the spellings, but I had the wrong N2 to O2 ratio I think).  Verbal is my one of my weakest abilities.

Well, as manufacturing goes 3D printers are a generalist, on the first few missions, the unexpected might be a factor, so I would want some generalist capabilities supported by innovative solutions (Software) from Earth.

The personal though?  Specialized as far as a narrow purpose, most efficient at that.  The 3D printer might save them, if events go outside of their specialized efficient abilities.

If you are talking exploration, then the scheme to escape danger might focus on leaving early.

If you are talking about the first construction crew, then maybe you send a drone/warehouse with robotic hard landers into orbit around Mars, with spare parts, 3D printers, and whatever, before sending the crew.

Then you send a split crew, some in orbit, and some early landers.

The early landers, set up the prelimary habitat and life support.  As they need it, additional supplies from the drone are dropped down by the orbital crew.  Spare parts, a 3D printer. 

Supposing that it starts as a experiment, and they do a final evaluation.  Is this location going to be worth building on.  Are the resources expected actually available and usable?  In the case of yes, then you send down more of the materials.  Otherwise abort and relocate at a later date.

If the location is confirmed and the construction crew intend to stay permanently, then after the hard landers are all used up, the orbital crew lands also, and the drone and unused parts remain in orbit, to be sold to anyone wanting them to set up a different base.

I am presuming that the drone would have been propelled to Mars not by chemical rockets, but perhaps efficient and slow electrical or solar sail or solar wind methods.

This after all would be a construction project, not the first landing.

Here are some thoughts about bringing plastic raw materials:
-What if the fuel tank of the hard lander were Plastic?  Could Kerosene be suitable for a lander fuel?
-What if such a parts lander had a cushion of crushable honeycomb made of plastic? 

Then those materials could be scavenged to feed into the 3D printer.

Where it might seem like I am proposing that I am not being real about the amount of materials that could be available in orbit, I would suggest that by the time such an activity like this were actually done, humans would have already been capturing small asteroids/rocks, and moving them the the Earth/Moon area, and in that situation, I do not think that the mass delivery to Mars orbit budget will be nearly as strict as if we were supposing a delivery from the Earths surface to the Mars surface.

Lewis said:

I agree, that the probability of a lavatube being located at an advantage, and particularly finding one under ice is currently diffacult.  But the person who initiated this thread had a specific set of requests, and I have tried to move forward on them.

However, I am thinking of a network of ice caves, sandstone caves, and lava tube caves (If lava tube caves are convenient).

The lavatube caves would be natural.  The ice caves and sandstone caves would be manufactured, slight chances exist for sandstone caves, but in their natural state they would likely not be of much value.

For ice caves, I am thinking of skyscrapers embeded in ice, with airlocks on the top, and connection to a sandstone deposite below.  The ice walls would help hold the structure's pressurization needs.

Here are some links to artificial sandstone caves.  For some sandstone, but not all, they might be possible:

http://www.environmentalgraffiti.com/ar … ve-temples

http://www.faribaultdairy.com/tourthecaves/

http://news.nationalgeographic.com/news … mers-hole/

http://www.google.com/search?q=californ … 93&bih=491

http://en.wikipedia.org/wiki/Wine_cave

http://www.napanow.com/wine.caves.html

I have no expectations, that we would want to first settle the high lattitudes, unless a submerged cave of convenience offered some unusual advantage, which I do not expect.

However, for all the intentions of terraforming Mars, it is also not practicle in my opinion to have a strong efficient Earth type habitat which covers a large scale of area in any realistic time frame.

We need a plenum.  On  Earth our plenum is the surface with a suitable atmosphere above it.

That will not be available on Mars any time soon.

Mice and other rodents, are helped by a snowfall in the winter.  They are small and will freeze without it.

I guess what I am looking for is a large scale network which can be expanded to great expanses.  I have said verticle ice caves filled with a verticle building.  I have also said sandstone caves which could be stable if the right sandstone pockets existed, and I think some will.  Beyond that for bulk transportation, on long distances, I suppose surface trains and roads with robotic trucks make sense.  However it might also be possible to have horrizontal subways in the ice (Which will require supports), or maybe even in the sandstone, and in some cases harder rock, which may not require support.

Solar collectors would need to be on the surface of course with robots to construct them from parts manufactured. (Above or below, depending on economics).  The verticle buildings in the ice would be the location to route power cables down to the caves.

In this case your water supply would be mined, either tunneling, or open pit.

I believe that solar collection will continue to become more efficient, and also lighting devices would be better.  So, it is not unreasonable to me to suppose that in some sandstone caves, you could have trees, most likely for fruit.  The trees would also be for human happyness.  The spectrum of light could be only that that the trees use when people are not visiting, but better light could be provided for those occasions when people want it.

Even more efficient will be chemosynthesis, where chemicals manufactured can drive a biological system.  Mushrooms will grow on soil contaminated with oil for instance.  I expect that the oil would have to be manufactured.

A harder to handle method would involve Hydrogen and Oxygen, which could be obtained from water and energy.

And of course their can be greenhouses on the surface as well.

I guess I have deviated from the "Initial Foothold" theme, but maybe "Initial foothold of a planetary civilization could be supposed".

I beleive that manufacturing materials for building a large scale plenum on the surface could be largely unprofitable, and sandstone under ice may exist in large quantities.  I think that large scale of pressurized space many be more profitable with this scheme.

I would want to figure out how to find lava tubes submerged under ground ice.  Tunnel down to them through the ice, and set up shop.  I would think that they would already be sealed by ice (Lava tubes have cracks), so they could be pressurized.  They could be warmed to a reasonable temperature that does not melt ice, and building methods more similar to what we do on Earth could be used, to provide accomodations for living and for factories.

Finding them would be hard, and I suppose it would almost have to be at high lattitudes.

Could some type of rover with a sonar which pings into the ice work to search for them?  I suppose you would have clues from the geology, to know that you were in a location where ice lies above a possible ancient volcanic location.