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#26 2004-06-05 02:10:40

MarsDog
Member
From: vancouver canada
Registered: 2004-03-24
Posts: 852

Re: Terraforming the Moon - Your opinion, please

Plasma in an experimental fusion reactor is confined magnetically. I wonder what kind of space based arrangement would confine or collect charged particles ?

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#27 2004-06-05 16:19:56

tricky1992000
Member
Registered: 2004-06-05
Posts: 3

Re: Terraforming the Moon - Your opinion, please

After reading mbastion's links:

Although it takes a long time to loose the Hydrogen, it takes longer still to loose the CO2 which gets left behind, as in the case of Venus. What gets left behind might be very hard to repair later. Just think of the Moon as a miniature Venus, CO2 atmosphere, H2SO4 clouds.
-
The effort and longer term consequences are not worth the short term result.

Water is much heavier than pure hydrogen, even vaporized, and it builds clouds in a thick atmosphere.

If Venus was given a "good" atmosphere and enough water it would stabilize and if the water cycle is created it would stay. Same with the Moon. Too much CO2 creates a runaway greenhouse effect. What if there was only 1-10% of it originally and the rest of it nitrogen, oxygen and water?

i have a point about hydrogen, hydrogen usually will combine with other substances before it gets the chance to escape, one of the concerns about the future hydrogren economy is that the extra hydrogen will attack the ozone layer.

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#28 2004-06-05 23:02:40

Shaun Barrett
Member
From: Cairns, Queensland, Australia
Registered: 2001-12-28
Posts: 2,843

Re: Terraforming the Moon - Your opinion, please

I think we're going to have trouble persuading the Moon to hang onto an atmosphere for as long as we'd like it to.
    I read somewhere of estimates of 3000 years for an atmosphere to leak away from the Moon, and some people here have read figures of 100,000 years.
    I have a feeling even the 3000 year figure is optimistic.

    Here at 'Terraformation', over in the 'Water not CO2' thread, I've been discussing leakage of helium, and by extension hydrogen, from Earth's gravitational field. In the process, I've had to look into various facts and figures and use them in a few calculations.
    It occurred to me to examine the situation of atmospheric loss from Luna, using the same kinds of figures. But this time, I've looked at the rate of loss of a mix of gases such as we have on Earth - i.e. 78.08% N2, 20.95% O2, and 0.93% Ar - with an average molecular weight of 28.94. This assumes we would be able to somehow import such an atmosphere in the first place (the O2 might be present in the regolith but I don't know about the nitrogen.)

    I have made some rough assumptions, which may be vulnerable to attack by those among us with better knowledge and data (I'll risk it! ). Firstly, I've assumed the exosphere of any new lunar atmosphere will be at a similar altitude above the lunar surface as Earth's is above terrestrial sea-level - about 800km. Secondly, since the Moon receives much the same insolation as Earth, I've assumed the kinetic temperature of gases at that altitude will be much the same as gases in Earth's exosphere - about 2000K.
    Using the formula for escape velocity:-
  V.esc = Sq. Rt. of (2GM/R)
            Where G is the Gravitational Constant
                      M is the mass of the Moon (kg)
                      R is the dist. from Luna's centre to 800km (m)
    And the formula for particle velocity in a gas:-
  V = Sq. Rt of (2kT/M)
            Where k is Boltzmann's Constant, 1.38066*10^-23
                     T is temperature (K)
                     M is the mass of a particle
    I have inserted the figures into the equations and the escape velocity 800km above the Moon is 2147m/s, while the average velocity of an air molecule at that altitude (i.e. at 2000K) is 1073m/s.

    These figures make it look as though the Moon will retain air molecules indefinitely but Maxwell and Boltzmann discovered that, in any gas of a given temperature, while the majority of particles (molecules, atoms etc.) move at speeds commensurate with the average temperature of the gas, a significant number of particles at any given moment will be moving much faster. (See the Maxwell-Boltzmann Distribution curve)
    From this, a scale has been developed based on the ratio of the escape velocity of a body, V.esc, to the average particle velocity of a gas, V.av, to give an estimate of how long the gas in question can be retained by that body (planet, moon).

    In the case of Luna, according to my figures above, the V.esc/V.av ratio is 2147/1073 = 2
    According to the scale of ratios (see the other thread at 'Water not CO2'), this means the Moon would lose an N2/O2 atmosphere in much less than 3000 years - perhaps not much more than 300 years!
                                                sad

    I admit some of my parameters are only assumptions and perhaps nobody really knows how gases would behave in an artificially constructed lunar atmosphere, but I think most of the figures I've seen for the Moon are looking way too optimistic.
                                                   ???


The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

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#29 2004-06-06 12:20:08

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming the Moon - Your opinion, please

Could a significan degree of cooling of only the exosphere be done?
What tech could be used for such job?

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#30 2004-06-27 12:52:34

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming the Moon - Your opinion, please

I have inserted the figures into the equations and the escape velocity 800km above the Moon is 2147m/s, while the average velocity of an air molecule at that altitude (i.e. at 2000K) is 1073m/s.

According to Gerald Nordley in his "Surface Gravity..." (a link is posted by Atitarev in "Mercury terraforming") if the termal velocity of the particles is 20% or lower than escape velocity in the (artificial atmosphere`s) exobase, than the body could retain earth-like atmosphere for billions of years.

If we find effective (plasma control, electromagnetical...?) method of 'refrigerating' the exobase + way of preventing the direct solar wind blow to graze out the atmosphere, than moon-size and smaller bodies, really could keep air on them indeffinitelly long.

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#31 2004-06-27 19:43:08

Martian Republic
Member
From: Haltom City- Dallas/Fort Worth
Registered: 2004-06-13
Posts: 855

Re: Terraforming the Moon - Your opinion, please

It sound like it will near to impossible to terraform the Moon. Unless we can generate some kind of magnetosphere and/or electromagnetic containment field and/or artificial bubble that we can fly through to hold the Lunar Atmosphere in, then we won't be able to get past building either underground chambers or specially built city's under glass above the lunar surface. There appear to be no apparent way to terraform the Moon.

Larry,

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#32 2004-06-28 12:22:35

MarsDog
Member
From: vancouver canada
Registered: 2004-03-24
Posts: 852

Re: Terraforming the Moon - Your opinion, please

Make the Moon into Earth's sister planet.
Just keep crashing objects, till it has the same mass as the Earth.
Wont be able to do it soon, but over the longer term
we could use another nearby planet.

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#33 2004-06-28 14:46:37

atitarev
Member
From: Melbourne, Australia
Registered: 2003-05-16
Posts: 203

Re: Terraforming the Moon - Your opinion, please

Make the Moon into Earth's sister planet.
Just keep crashing objects, till it has the same mass as the Earth.
Wont be able to do it soon, but over the longer term
we could use another nearby planet.

I don't think it's a good idea. There's a balance between Earth and the Moon, we don't want to break it. Also, the dust created after such measure will last for eons. Terraform what's terraformable. The Moon can be to a degree - need to create a magnetic field, dump a lot of ice asteroids and see what happens. It may hold to the atmosphere for a significant time - in some people's opinion indefinitely. In the worst case scenario, we can dome Luna.

Low Surface Gravity - Terraforming (read me)


Anatoli Titarev

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#34 2004-06-28 15:11:47

Martian Republic
Member
From: Haltom City- Dallas/Fort Worth
Registered: 2004-06-13
Posts: 855

Re: Terraforming the Moon - Your opinion, please

Make the Moon into Earth's sister planet.
Just keep crashing objects, till it has the same mass as the Earth.
Wont be able to do it soon, but over the longer term
we could use another nearby planet.

I don't think it's a good idea. There's a balance between Earth and the Moon, we don't want to break it. Also, the dust created after such measure will last for eons. Terraform what's terraformable. The Moon can be to a degree - need to create a magnetic field, dump a lot of ice asteroids and see what happens. It may hold to the atmosphere for a significant time - in some people's opinion indefinitely. In the worst case scenario, we can dome Luna.

Low Surface Gravity - Terraforming (read me)

Then we could use an elevator system to get away from lunar shuttles that might crash into those domes.

But, I still favor magnetic field and possibly some kind of bubble technology that you could still fly through, but could be use to argument the lack of gravity on the Moon. Maybe I just been watching too much Science fiction, so never mind.

Larry,

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#35 2004-06-28 18:13:25

MarsDog
Member
From: vancouver canada
Registered: 2004-03-24
Posts: 852

Re: Terraforming the Moon - Your opinion, please

I like the "fully tidally evolved", Pluto-Charon,  "double planet" system.
Similarly, Earth and sister planet Moon, would have advantages.
The Earth has excessive oceans and some of the water could be space elevatored to the Moon.

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#36 2004-06-29 08:45:28

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming the Moon - Your opinion, please

But, I still favor magnetic field and possibly some kind of bubble technology that you could still fly through, but could be use to argument the lack of gravity on the Moon.

Anyway, some kind of active or passive atmosphere-protection mechanism must be applicated on Moon and other 'smaller bodies' terraform. Constant replenishing and leaving the atmosphere to escape is not so long-run and economical solution.
-
About the passive ones: There were proposed during the years many types of doming the entire world -- even incrementaly widened plastic envelope which to be lied on surface, pumped with air underneath and grown wider-and-wider untill it covers whole the planetary body -- finally hovering by the contained atmosphere, This is in the middle between 'parateraforming' using big towers with ropes run between them with tent cloth over and mere atmosphere contra-leakage measures. In the world-blanket concept we see way of simple mechanical deflecting the particles trying to escape -- and we should recognise that such method has some advantages -- it is power-supply independent, but needs constant repair; or even big hole in it, really substantial part of the canopy`s area loss would not mean immediate getting worse of the biospheres conditions. Repair it or rise new one and stop the leak. I met a proposal the blanket to consist of hexagonal grid of ropes with specially designed transperant plastic 'windows' -- a plastic which polimerizes and is quite rigid under UV radiation, but liquid in storage. Repair robots, like spiders run over the grid, and sqeeze the plastic to fill the gaps from meteors or passing SHIPS which 'dries' like soap bubble afetrwards...
-
The bubbling could be done by even not so rigid material. It couold consist of something like the Utility Fog -- countless thiny smart-dust particles which to interact (say creating by solar power mini-magnetospheres and to regulate the exchange of light and gass around the body.). Such swarm could consist either from quite big meso-units (cantimeters, or even meters wide) or host or real mature tech self-replicating nano-robots. The last version could be as sophisticated as the lower human-compatible protoplasmic biosphere and to amplify the homeostatic Gaia effect to super-extremes: to collect light from the necessary area for the distant world and to create hyper-greenhouse effect unachievable with any kind of gas, or vice versa to deflect the light, to filter it, to change it colour, to produce light, to arrange overall mag-field with very complex topology... Such way a habitable world could be very close or remote with accordance to any central star -- a nanotech multipurpose soletas!!!
-
But, AGAIN, the Moon is big enough so only artificial magnetosphere (generated by single equatorial superconducting ring -- a 'landed mag-sail') + exobase cooling should be enough the volatiles on it to stay indeffinitelly long - comparable with the rest of the Sun`s lifetime and longer.

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#37 2004-06-29 08:54:54

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming the Moon - Your opinion, please

I like the "fully tidally evolved", Pluto-Charon,  "double planet" system.
Similarly, Earth and sister planet Moon, would have advantages.
The Earth has excessive oceans and some of the water could be space elevatored to the Moon.

Making Earth-Moon systems 'twin geosinchronous' is not at all economical. Such projects would be done by very bored and very rich societies OUT of the Solar system.
-
About Pluto-Charon: Indeed, the deorbiting of the tidally locked Charon on Pluto in controled manner, in little doses by Orbital rings` momentum exchange mechanism, could provide a society of billions with all the necessary industrial energy, including the garden type biosphere to be illuminated, too for geological eras long time, absolutelly independent from the Sun or nuclear fusion. On Pluto the landscapes could be light-lit from huge lamps floating very high in the produced and heated atmosphere... powered by incrementaly falling Charon.
-
Such scheme is applicable for free-floating planetary systems without central star in the interstellar void -- ejected or such formed ones.

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#38 2004-06-29 15:20:13

Martian Republic
Member
From: Haltom City- Dallas/Fort Worth
Registered: 2004-06-13
Posts: 855

Re: Terraforming the Moon - Your opinion, please

But, I still favor magnetic field and possibly some kind of bubble technology that you could still fly through, but could be use to argument the lack of gravity on the Moon.

Anyway, some kind of active or passive atmosphere-protection mechanism must be applicated on Moon and other 'smaller bodies' terraform. Constant replenishing and leaving the atmosphere to escape is not so long-run and economical solution.
-
About the passive ones: There were proposed during the years many types of doming the entire world -- even incrementaly widened plastic envelope which to be lied on surface, pumped with air underneath and grown wider-and-wider untill it covers whole the planetary body -- finally hovering by the contained atmosphere, This is in the middle between 'parateraforming' using big towers with ropes run between them with tent cloth over and mere atmosphere contra-leakage measures. In the world-blanket concept we see way of simple mechanical deflecting the particles trying to escape -- and we should recognise that such method has some advantages -- it is power-supply independent, but needs constant repair; or even big hole in it, really substantial part of the canopy`s area loss would not mean immediate getting worse of the biospheres conditions. Repair it or rise new one and stop the leak. I met a proposal the blanket to consist of hexagonal grid of ropes with specially designed transperant plastic 'windows' -- a plastic which polimerizes and is quite rigid under UV radiation, but liquid in storage. Repair robots, like spiders run over the grid, and sqeeze the plastic to fill the gaps from meteors or passing SHIPS which 'dries' like soap bubble afetrwards...
-
The bubbling could be done by even not so rigid material. It couold consist of something like the Utility Fog -- countless thiny smart-dust particles which to interact (say creating by solar power mini-magnetospheres and to regulate the exchange of light and gass around the body.). Such swarm could consist either from quite big meso-units (cantimeters, or even meters wide) or host or real mature tech self-replicating nano-robots. The last version could be as sophisticated as the lower human-compatible protoplasmic biosphere and to amplify the homeostatic Gaia effect to super-extremes: to collect light from the necessary area for the distant world and to create hyper-greenhouse effect unachievable with any kind of gas, or vice versa to deflect the light, to filter it, to change it colour, to produce light, to arrange overall mag-field with very complex topology... Such way a habitable world could be very close or remote with accordance to any central star -- a nanotech multipurpose soletas!!!
-
But, AGAIN, the Moon is big enough so only artificial magnetosphere (generated by single equatorial superconducting ring -- a 'landed mag-sail') + exobase cooling should be enough the volatiles on it to stay indeffinitelly long - comparable with the rest of the Sun`s lifetime and longer.

You talking about putting the Moon in a plastic bubble around the entire Moon. Like you said, it going to be very high maitaince, but you would probably want two or three layer, because of the high maitaince of it and patch each of the separate layer. But, in a system like that, you would defenetly want an elevator to the surfice of the moon from orbit.

But, if such a project were to be under taken, you would have to have some major government to finance the start of such a major project. But once you get into such a project, then it would need to be turned over to the Lunar Central government to finish and maitain.

And even then it would have to be done in stages.

Larry,

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#39 2004-06-30 06:35:09

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming the Moon - Your opinion, please

You talking about putting the Moon in a plastic bubble around the entire Moon. Like you said, it going to be very high maitaince, but you would probably want two or three layer, because of the high maitaince of it and patch each of the separate layer. But, in a system like that, you would defenetly want an elevator to the surfice of the moon from orbit.

But, if such a project were to be under taken, you would have to have some major government to finance the start of such a major project. But once you get into such a project, then it would need to be turned over to the Lunar Central government to finish and maitain.

And even then it would have to be done in stages.

A plastic bubble for enveloping the entire Moon is the closest to the present day technology which we can imagine for indiscrete covering. This plastic bubble or rather tent has enormous combinatorical space of possible designs. Its obvious that like simple crater dome it has to suffice the requirements for balance between the internal air presure and gravity. The plastic tent could be anchored or not. To be traversible the cover should be celled and selfrepairing or consisting of many moving discretely interacting 'baloons'.
If the cover is single-sheet ( say, multilayered) it could be also armatured with ropes allong with to run the repair 'spiders'. If the cells doesn`t burst and loose the structural material (say, become liquid and condense on the fillament ropes and afterwards cover the hole and solidify) than the maintainance should not be so high and would allow ship traffic to pass frequently through it. Remember that even vast loss of coverage would not be fatal, the air needs at least millennia to leave the Mon gravity. But the elevators and towers are usefull structures and I think they`ll be implemented. A simple tower made by conventional materials can have hundreds of km hight under moon`s gravity. Space fountain towers are also efficient. As well orbital rings systems - partial or global - descending to the ground. Also synchronous kevlar-type material scyhooks to L1 and L2... It will be undoubtly good if we pass the membrane purelly mechanicaly without punturing or impacting it.

Global lunar autoruity to deal and regulate the roofing could be tightly specialized and can have lots o organisational forms.

...in stages yes in order the financial effort to be distributed in time within the abilities of the credit/bank system + real estates bussiness. Lie plastic sheet and pump it. Get it wider and wider untill it encompass eventually the whole moon...

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#40 2004-07-01 07:43:24

Shaun Barrett
Member
From: Cairns, Queensland, Australia
Registered: 2001-12-28
Posts: 2,843

Re: Terraforming the Moon - Your opinion, please

It's all well and good to be designing hi-tech solutions to the problem of retaining air on a celestial body with low gravity but I think the low gravity will lead to other, more serious, problems.
    While you might get away with living on Luna, at 0.16g, and avoid debilitating muscle and bone loss (nobody really knows), lower gravity than that must surely cause drastic physiological deterioration, even in the short to medium term.
    And, even if you can live comfortably on the Moon, you'll never be able to visit Earth again, once you've acclimatised to lunar gravity. In fact, I have very grave doubts that anyone who becomes accustomed to living on Mars in 0.38g will ever visit Earth either - at least not without major medical assistance and help of other kinds.
    In addition, a native Lunarian may well find Mars and Mercury intolerable, too, and thus be forever restricted to the Moon and the satellites of the outer planets.

    I think we'll need to address important human physiological limits before we worry too much about forcing a tiny world to retain an atmosphere.
                                          ???


The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

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#41 2004-07-01 08:36:01

MarsDog
Member
From: vancouver canada
Registered: 2004-03-24
Posts: 852

Re: Terraforming the Moon - Your opinion, please

Artificial Gravity will be needed.

I wonder why athletes dont spend time in a greater than 1 G environment. Would that be considered doping ? All of a sudden a 5 foot basketball player dunking the ball.

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#42 2004-07-02 10:51:47

REB
Member
From: Houston, Texas
Registered: 2004-04-07
Posts: 555
Website

Re: Terraforming the Moon - Your opinion, please

The Moon’s low gravity would be a great place for the elderly. It would also be good for people who can not walk (Zero G may be better for that)

A retirement community on the Moons sounds good. That is were I want my kids to put me.

Of course, to get off the Earth, something like a space plane would be better than a rocket.


"Run for it? Running's not a plan! Running's what you do, once a plan fails!"  -Earl Bassett

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#43 2004-07-02 16:46:43

atitarev
Member
From: Melbourne, Australia
Registered: 2003-05-16
Posts: 203

Re: Terraforming the Moon - Your opinion, please

It's all well and good to be designing hi-tech solutions to the problem of retaining air on a celestial body with low gravity but I think the low gravity will lead to other, more serious, problems.
    While you might get away with living on Luna, at 0.16g, and avoid debilitating muscle and bone loss (nobody really knows), lower gravity than that must surely cause drastic physiological deterioration, even in the short to medium term.
    And, even if you can live comfortably on the Moon, you'll never be able to visit Earth again, once you've acclimatised to lunar gravity. In fact, I have very grave doubts that anyone who becomes accustomed to living on Mars in 0.38g will ever visit Earth either - at least not without major medical assistance and help of other kinds.
    In addition, a native Lunarian may well find Mars and Mercury intolerable, too, and thus be forever restricted to the Moon and the satellites of the outer planets.

    I think we'll need to address important human physiological limits before we worry too much about forcing a tiny world to retain an atmosphere.
                                          ???

Hi Shaun, smile

In my opinion we should terraform/paraterraform bodies with the lower gravity too. Even if we end up with the worlds full of plants and animals, with no humans, it is worth doing it for preservation of species and expansion of life forms. However, the planets/moons with the lower gravity will be populated anyway, temporarily or permanently. By the time the Moon is terraformed we will know the exact effect of the lower G on the human body. People will still want to settle the Moon to make it their home, even if they or their kids will never be able to visit Earth. We don't know what technology could be used in the future to allow just that if necessary. Lunarians (Lunites?) might want to adapt to Martian G first, before visiting Earth.

Bodies like the Moon are more common in the Solar system and more probability that find a lot of Luna-sized bodies elsewhere than Terra-like bodies. Even smaller bodies like Titania or Triton will be even more common. Native Tritonians will have trouble even visiting the Earth's Moon! The trouble starts when not only large planets/moons are colonized but smaller moons (Saturn's Rhea, Uranus's Umbriel, Miranda) and large asteroids - Ceres, etc.

The larger bodies should be settled first, taking into account the terraformability and the efforts required, e.g. Mars before Venus, then Mercury or the Jovian moons (Callisto and Ganymede first).

Groups of planets with similar gravity (only the largest):
Earth-Venus
Mars-Mercury
Luna-Ganymede-Callisto-Titan-Io-Europa
Titania-Oberon-Triton-Pluto-Charon

As you can see, Mercurians will be comfortable with the Martian G, Lunar people with the G of the 4 moons.

Planets/Moons and the surface gravity in descending order - not 100% accurate but pretty close (better viewed in MS Excel)
Planet/Satellite Name    Observed surface gravity (m/s2)
Earth    9.81
Venus    8.87
Mercury    3.9
Mars    3.8
Io    1.79
Moon    1.62
Ganymede    1.42
Titan    1.36
Europa    1.31
Callisto    1.23
Triton    0.783
Pluto    0.651
Titania    0.372
Oberon    0.346
Charon    0.334

I know there's going to be some experiments on mice/rats - on how they can handle 0 or lower G's and if their offspring can survive back on Earth. I'm interested to know about this development.


Anatoli Titarev

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#44 2004-07-03 09:45:48

Gennaro
Member
From: Eta Cassiopeiae (no, Sweden re
Registered: 2003-03-25
Posts: 591

Re: Terraforming the Moon - Your opinion, please

When the time comes, I'm not sure humans will decide to become permanent residents on very low gravity objects at all, considered the physiological implications.
If you want to extract He-3 from gasgiants for your fusion interplanetary ships, building orbital 1g bases to serve the mining community sounds simpler and more practical to me, than enormous terraforming projects requiring centuries to complete.
The first outposts around Saturn or Uranus will be relatively small facilities, but they could expand considerably in size and complexity, given time and resource flow, until they reach a level where they are virtually full-fledged societies all on their own.

Rocky planets here and in the stellar neighbourhood are another matter though. They will be terraformed and become kins to Earth eventually.

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#45 2004-07-03 12:31:49

MarsDog
Member
From: vancouver canada
Registered: 2004-03-24
Posts: 852

Re: Terraforming the Moon - Your opinion, please

Going to take very long time.
But considering how far we have advanced in the last few hundred years; People were too simple before the industrial revolution, now, combined with intelligent robots, might happen sooner.
-
I suspect that we will dismantle one of the outer gas giant planets for fuel. And use the core, as material, to renovate the inner solar system;
-
Double planets, one double  beyond Venus orbit, Double Earth Moon, and another double planet in Mars orbit. Six planets in total.

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#46 2004-07-04 06:47:38

atitarev
Member
From: Melbourne, Australia
Registered: 2003-05-16
Posts: 203

Re: Terraforming the Moon - Your opinion, please

When the time comes, I'm not sure humans will decide to become permanent residents on very low gravity objects at all, considered the physiological implications.
If you want to extract He-3 from gasgiants for your fusion interplanetary ships, building orbital 1g bases to serve the mining community sounds simpler and more practical to me, than enormous terraforming projects requiring centuries to complete.
The first outposts around Saturn or Uranus will be relatively small facilities, but they could expand considerably in size and complexity, given time and resource flow, until they reach a level where they are virtually full-fledged societies all on their own.

Rocky planets here and in the stellar neighbourhood are another matter though. They will be terraformed and become kins to Earth eventually.

You must be more excited about Mars than the Moon, Gennaro. Mars has the same problem as the Moon to a lesser extent. There is simply no other planet like Earth. If you want Earth gravity stay on Earth or go to Venus. If other planets are comfortable and good for living I don't see why people will not go to live there. A few years in a lower gravity won't do so much damage to an adult person and they can still decide to come back to Earth. If someone decides to settle on Mars, the Moon, Callisto for good, knowing the consequences of living in the low G, it's their choice. It's their new home. The Solar system is scarce in large solid planet, Earth is the largest. If we had solid (Earth-like) larger planets with higher G, would that be a show stopper for settlement? I don't think so. If a planet can be settled it will be. That's my strong opinion.

How bad is low G for humans in the long term - we don't know for sure. Is there a remedy - not yet. Will the humans living in low G be banned from visiting Earth - I don' know. If they come back to live - they could probably adapt slowly, if they come to visit - they could stay in aquariums in scubas smile

As for using resources of gas giants, it's another topic. Solid planets/moons have the biggest value when terraformed/colonized - livable land.


Anatoli Titarev

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#47 2004-07-04 18:00:38

Gennaro
Member
From: Eta Cassiopeiae (no, Sweden re
Registered: 2003-03-25
Posts: 591

Re: Terraforming the Moon - Your opinion, please

Well, not to sound dogmatical; I sure like the idea of terraforming moons, using wings to fly like Ikaros etc, but yes, I am more excited about Mars than Luna when it comes to permanent settlement. Partly because the gravitation issue, but also because the moon seems mostly like a lump of worthless scrap material. Apparently, or as far as we currently are aware, there's almost nothing there, just a depressing dusty grey landscape.

Yes, Mars has the same problems to a lesser extent, but hopefully that lesser extent is qualitatively crucial when it comes to gravitation.

When civilisation is sophisticated enough to settle numerous locations in the solar system, propulsion systems will also have evolved to a high degree. Even now it only takes six months to reach Mars. People in the future will want to move around, not just stay on one body forever. If settlement is tantamount to indefinite seclusion because of physiological detriment, it will likely be regarded a health hazard or at least not a very attractive prospect.

Mining gasgiants are closely intertwined with the very reason to settle the outer solar system. These things should be regarded as interconnected, in my opinion. Nobody would like to live forever on a dark unforgiving iceworld, let alone financing a growing colony if there wasn't a relation to material factors. Civilization advances with the transformation of capital and the modes of production.
If I'm not believable we should ask why people aren't living in Antarctica today.

My main point however, is that terraformation of certain locations seem like such huge undertakings, not least in a temporal regard, that we might even find promising exosolar worlds around 61 Cygni or Alpha Centauri before they are finished. In the meantime, space stations in the outer solar system could serve every need a similarly artificial environment on Titan could provide, only with the bonus of a healthy and comfy 1g, or whatever we'd prefer. In principle there is neither any limit to their size and diversification, provided future generation will feel that artificial is good.

Above all, some terraformation scenarios require massive adjustments before settlement can commence. Space stations on the other hand can grow and multiply incrementally.
Culture will then adjust preferences to the historical paths taken.

Although, I'll have to say that reconditioning in scuba tanks sounds like kind of fun in their own regard.
smile

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#48 2004-07-04 19:48:11

atitarev
Member
From: Melbourne, Australia
Registered: 2003-05-16
Posts: 203

Re: Terraforming the Moon - Your opinion, please

Thanks, Gennaro. I don't want to discuss the Moon vs Mars issue. A lot of people have done this already. And Mars is my preferred first candidate for settling/terraforming too for various reasons. Nevertheless, the Earth's Moon will be candidate number 2 for most people, not Venus, Mercury, Callisto or Ganymede (some will disagree but the majority of terraforming enthusiasts will agree) and should not neglect it. That's why I started this discussion. Bringing volatiles to the Moon - gases and water would be easier than cleaning excess atmosphere on Venus (possible but much more work required), Mercury has its own big problems, probably not terraformable in the pure sense, the Jovian moons are too far away and G is even lower than on the Moon. Whatever you say, Mars and the Moon will always be the frontrunners in settlement. Of course, it's a problem for people deciding to stay on a low G body, if they can't move around easily but medicine may get get some answers to this problem, hopefully.

I agree we need to investigate and know all consequences, more research should be done on long exposure to low G. Vitamins and lots of exercise would be the answer for temporary visits - even few year contracts are possible (the lower the G, the shorter contracts could be).

It's going to be some time before anyone will have a chance decides to settle on another planet/moon. It's hard to predict how good the environments could get. Obviously, no-one is going to rush to a desert planet.


Anatoli Titarev

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#49 2004-07-05 00:00:52

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming the Moon - Your opinion, please

..."moon seems mostly like a lump of worthless scrap material"...

Yes, that`s why it is suitable only as a atmosphere holder, as a piece of land, a real estate. Each 'advantage' of the Moon as 'perfect vacuum place' for extracting usefull materials or placing teleescopes and solar arrays are indeed many times surpassed by the condition in the nakd vacuum or the asteroids, especially the NEAs... It may occur that the Moon is usefull only in this role -- being terraformed.

As atitarev and many others pointed out - it is much more easier to cover a vacuum world with atmosphere/hydrosphere than to try to get rid of thick one as in the case of Venus, or to deal with constantly outgasing surface - spoiling the new atmosphere as in the Mars case... BTW on the Moon are already present some of the gases. Pyrolising, or processing in other - not so agressive way, a cube of lunar soil/rocks of some several dozens of kms. linear dimensions -- will release quickly (copmpared with photosynthesis in nonoxigenated preliminary air cover) all the necessary O2. Part of the ballast filling of the atmosphere could be argon-40. The carbon + hydrogen + nitrogen should be imported -- but mature solar system wide momentum exchange transport mechanism or other means of redirecting mass flows in mega-scale, could do the job...

The atmosphere retention measures were already discussed in enough number of solutions. We deffinitelly know what to do to keep an atmosphere for billions of years around moon-size body. The question is how exactly to do this. What will be economical?

The low gravity issue regarded as stopper in medical sence, should be solved in the field of the medicine. Say, the nano-technology or insignificantly small reversible genethic transcription or inscription, could stop the bone loss or other low G changes in the human organism in order the low G colonists to not be confined to their group of wolds.

Indeed as we discussed there is strong economical presure towards colonising, i.e. terraforming the smaller worlds being so much numerous here in the solar system and perhubs abroad. So, there is big possibility the mutual visitabilty of the low and normal G worlds to be solved problem.

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#50 2004-07-12 22:01:10

Mad Grad Student
Member
From: Phoenix, Arizona, North Americ
Registered: 2003-11-09
Posts: 498
Website

Re: Terraforming the Moon - Your opinion, please

I'm just going to hit on a few of the issues I saw when I breifly scanned the topic. It's been proven that the Moon's crust is mostly silicon dioxide (SiO2). If you could free enough oxygen from that combo, you could easily make a pretty thick atmosphere, temporarily at least. There are serious problems, though, you need carbon to free oxygen from SiO2, which is virtually nonexistant on the Moon. Perhaps you could ship it in from the asteroid belt, but again we run into the question of "who's paying for it?"

With carbon you can turn SiO2 into one silicon atom and two CO molecules. I think that you can then get CO2 from the carbon monoxide and recycle the one surplus carbon atom back into the reactor. With some hyrogen you could make free oxygen from the CO as well, and once enough of it got into the atmosphere it would create a nice ozone layer around the Moon. So we've now solved the problem of radiation, made the air breatheable, and turned the thermostat to a reasonable setting planetwide. Still, there are massive problems on the Moon.

The 28 day day/night cycle and the lack of water will be tough to solve. The only way you could even think about solving them is to ram a whole bunch of iceteroids from the Kuiper Belt into the Moon pushing its rotation along. The problem is, in order for the iceteroid to hit the Moon hard enough to have an effect, it would blast pretty much all H2O out with it. Another set of these KBOs would have to be sent on a trajectory that would make them impact the Moon at very low speeds. As an added bonus, spinning the Moon until you get a day down to, say, 96 hours, would cause emense tidal shearing, perhaps melting its mantle and starting a magnetic field which could keep the atmosphere for you.

Still, the Moon need some CHNOPS (Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorous, Sulfur, the stuff of life). Once again, you'll have to ship this stuff in from the asteroid belt, but it will be easier once there's a noticable atmosphere since you can aerobrake. So there you have it. One huge mess of headaches and MADMEN, plus centuries of hard work, get you a shirtsleeve environment Moon. There is no way in hell any Terran country would even touch such a plan, but a Lunar Republic just might. If we ever actually get the Moon like this, it's going to need a better, more distinctive name. How about Diana? Wasn't that the original Roman name for the thing?


A mind is like a parachute- it works best when open.

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