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Terraforming ganymede

  1. Nov 20, 2007 #1
    a great posibility for a planet to spread life to is ganymede. i mean, its got the basics for life; water oxygen and light ( not that much for days are are about 3.2 earth days). the only problem is its darn cold and its atmosphere is so dense that for a human it would be like brathing on top of a mountain three times higher than mount everest. is there a posibility that we could manipulate co2 and make ganymedes atmosphere have a high enough pressure for us to live on? :confused:
     
  2. jcsd
  3. Nov 20, 2007 #2

    LURCH

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    I don't think Ganymede has a strong enough gravitational field to hold an atmosphere that thick. Human habitation would probably need to be underground.

    BTW; this would probably get more responses in a different Forum. Maybe Astrophysics.
     
    Last edited: Nov 20, 2007
  4. Nov 20, 2007 #3
    I think the OP meant "thin" rather than "dense", and I'd say it's unfixable due to the weak gravity. For humans there, we'd probably want fusion power and rotating habitats, so it doesn't sound like the first site we'd want to colonise.

    On the other hand (note how I make this thread relevant to this solid state forum) if our high temperature superconductor program generally fails to meet ambient Earth-temperature, the low external temperature (and low atmosphere density) of these moons might be perfect for very long efficient maglev (gravity-simulating) trains. :biggrin:
     
    Last edited: Nov 20, 2007
  5. Nov 20, 2007 #4

    Integral

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    This topic has nothing to do with Solid state physics. Moved to general engineering for lack of a better place.
     
  6. Nov 20, 2007 #5
    Just one point. Ganymede is larger than Titan, which holds an atmosphere just fine. So, it can probably hold an atmosphere.. does it have the gravity to hold an Earthlike atmosphere (assuming temperture and chemistry weren't issues)? I don't know.
     
  7. Nov 20, 2007 #6
    i guess it could not hold the atmosphere but if it could how would we manipulate it?
     
  8. Nov 20, 2007 #7
    Ok.. lets talk completely hypothetical. Ganymedes surface is mostly ice. If we could somehow raise it temperture, much of the surface would vaporize. This would certainly create an atmosphere. Thick one too. But nothing you'd want to breathe.
     
  9. Nov 21, 2007 #8
    mawm,

    ganymede has a crust of rock few km deep and under that is the water/ice. what would happen if we melted it? and if the gravity was increased then could we make the atmosphere breathable?
     
    Last edited: Nov 22, 2007
  10. Nov 21, 2007 #9
    Hmmm.. no ice on the surface? That doesnt seem right. I'm pretty sure the ice is on the top. And if we could get the world to our kind of temperture, we'dporobably get a nice atmosphere of methene, CO2, water vapor and cyanide.
     
  11. Oct 14, 2010 #10
    I believe it is Ganymede has a mass and gravitation similar to Saturn's moon Titan. Which has an atmospheric pressure 50% thicker than that of Earth. Those gases on Titan probably exist (Nitrogen Methane etc.) because the can exist in cold tempuratures. Both of these are natural moons mostly ice and rock. But if the ices were melted to the point of evaporation under temperatures hotter than the sun (Hydrogen bombs) with hydrofluorocarbons 1,2500 times more potent than CO2 and ozone friendly perhaps it's possible. Electrical arcs and high radiation can create ozone (O3) naturally by splitting ionization or dislocation of molecules naturally this may be possible. Think out of the box ya'll :D
     
  12. Oct 14, 2010 #11
    Well look at Titan for instance slightly smaller mass and size than Ganymede but with a thicker atmosphere than Earth by 50%. It's atmospheric components can be etreme of course nitrogen can exist at cold tempuratures as well as methane and ethane. Titan has lower gravitation than our moon. Both Ganymede and Titan and many satellites are mostly ice and rock.
     
    Last edited: Oct 14, 2010
  13. Oct 14, 2010 #12
    Let me add that it's easy to freeze water ice and harder to freeze nitrogen. On earth the atmosphere is thinner at the poles and thicker at the equator. Hence it's what's the atmosphere is made of. If that atmosphere is to keep heat and stay thick further out you may wish to add more of a greenhouse gas influx.(Ozone friendly)
     
  14. Oct 14, 2010 #13
    It might depend on the type of ice your trying to vaporize. If you detonante hundreds of Tsar Bomba like hydrogen bombs across it's surface for a burning inferno of heat. Say for instance the vast majority of ices is water ice CO2 ice a a bit of nitrogen and or methane. All of it would vaporize and rise into the atmophere/ Hydrogen would split from O2 and oxygen molecules may combine and make O3 for instance(Ozone) CO2 would flow freely as a gas amplifying and trapping the 19% sunlight it gets perhaps making it warm enough for that atmosphere to stabilize if not add hydroflouro carbons later :). Note CO2 is real low in earth's atmosphere in comparison to other gases. Thank goodness. :)
     
  15. Oct 14, 2010 #14
    We may be able to terraform it dude look at the previous posts :D
     
  16. Oct 14, 2010 #15
    It can I'm confident it can because Titan is able to hold one thicker than Earth both Titan and Ganymede have slightly lower gravitation than our moon. Look at the otha posts dude Lol :D. I'm optimistic
     
  17. Oct 14, 2010 #16
    I have no worries about that. I don't think it's too extreme for plants not to adapt. Lol. Like an odd more time for food but having an odd more time for sunlight. We all naturally adapt to our enviroments. Like people living in high to low alttitudes. Tropical or other areas. We naturally adapt to our surroundings and may not notice it. As long as we can terraform the moon to a sufficient degree.
     
  18. Oct 15, 2010 #17
    The gases that a planet/moon can hold onto are a function of temperature as well as gravity...specifically, escape velocity and mean particle velocity at the top of the atmosphere. Titan's atmosphere is thick because it is extremely cold, it would be lost very rapidly if it were warmed up to Earthly temperatures.

    A far bigger problem than the rotation period is the fact that it gets only 3-4% the sunlight of Earth. That's not enough for plants to thrive...some slow-growing plants might survive those illumination levels, but they'd be limited by the low amounts of energy they receive...and not nearly enough to keep the place warm. Artificial light and heat would be a necessity, and vastly more expensive than just constructing enclosed habitats instead. Terraforming Ganymede wouldn't just be impractical and pointless, it'd be counterproductive...you'd be turning it into an insanely inefficient unenclosed habitat, and in the process destroying all the potentially useful attributes of the original environment, like the above mentioned surface temperatures cold enough for superconductors to operate with minimal cooling, or the lack of an atmosphere to get in the way of mass driver assisted launches.

    This isn't pessimism...there's no planet or moon in the solar system that can be easily terraformed, but we don't need to terraform any of them, and in fact stand to benefit by taking advantage of some of their differences from Earth. Look at the other possibilities...vacuum allows greater speeds to be achieved on the surface and insulates superconductors and cryogenic fuel storage tanks, while not impeding sunlight used for solar power or launches into orbit. Frozen ices are easy to mine for fuel and burrow into for well-shielded living spaces. Etc...
     
  19. Oct 16, 2010 #18
    You provided good points in many areas, and you are very right in so many points. Though one underlining theme may present itself as it does today. Economically speaking cost. Also not meaning to appear pessimistic. You would have to operate carefully in a vacuum and every member working there would need protection against a variety of things while the construct these things factoring in tourism. Titan was used as an example that though it had low G relatively small size and mass its components could exist in those tmperatues in some form(Nitrogen, methane, ethane etc.) Though water vapor and CO2 would not. These are green house gases to earth's atmosphere trapping heat. Your right Titan gets minimal light. Though jupiter being estimated 5.2 AU Ganymede may recieve just enough heat and warmth 19% of Earth. You would just have to keep it "lit" from refreezing then implying more green house gases. Perhaps after global thermonuclear detonations. You can still use solar panels at that distance and comets become active and at that distance as well underlining the possibility. The Earth's atmosphere has less than 1% of CO2 and perhaps other trace green housegases and see what it has done?!? Once oxygen splits from hydrogen in the vast amounts of water ice on ganymede. Then vaporize naturally (O3 ozone) from radiation as easily as it forms from ionizing electrical arcs on earth. Now a vacuum makes sense for space travel but in a sense of priority of pace tourism and manufacture it seems easier and a bit more cost effective to have an earth like biosphere for relaxation looking up into the jovian sky and for working on building those materials needed further out as a refreshing nostalgic waystation. The gravity would be similar to the moon already imagine how easy would(hypothetically) for the apollo astronauts without those"bulky but light already in lunar gravitation). As landing on the moon was a fearfully but time consuming maybe and maybe not but it was indeed possible. We came from figuring out how to get into orbit toward the moon in 8 years factoring in cost. Optimistically speaking, we don't know until we try it's a maybe so or maybe not. The impossibles of yesterday are proving possible today. Mars has water ice? Short liquid flows? Before it was thought only CO2 ice existed and it's GRAV was to low to hold a thick atmosphere and a no magnetic field. Venus has no magnetic field look at it's atmosphere! Those assumptions indeed contradicted what exists in our solar system. In all confidence may I imply that its highly beneficial to terraform at minimum Mars and a moon in the Jovian system Ganymede to make to bring things from home to makes the voyage more comfortable and reasuring. Nothing great ever strived and worked for was easy. There's nothing like a blue sky for the heart.
     
    Last edited: Oct 16, 2010
  20. Oct 16, 2010 #19
    When it's at 5.2 AU from the sun, Ganymede gets 3.7% of the sunlight Earth does when it's at 1 AU. I was speaking about the Jovian moons when I said 3-4%, not Titan, which gets closer to 1%. Again, plant life is not going to thrive as it does on Earth with 1/27th the light. It's not a matter of adaptability, there's just the fact of having 1/27th the energy to work with. Mars would have enough issues, with about half the light.


    The possibility of what? It's not hard to evaporate water, ammonia, CO2, and other ices in vacuum. It's a simple fact that there's not much energy input from the sun out there.


    What has it done? It's not hard to maintain Earthlike temperatures at Earth's distance from the sun. Without that <1% CO2, Earth would have a fairly similar temperatures. A super greenhouse effect isn't going to make Ganymede Earthlike.


    Terraforming is not remotely cost effective. It would be vastly cheaper to establish and maintain Earthlike conditions in large enclosed habitats, even on a world like Mars which is relatively well suited to terraforming. You'd be better off enclosing all of Ganymede than you would be trying to build and maintain a breathable atmosphere and sun-powered ecology there.


    The gravitational field of Mars was too low to hold a thick atmosphere. And the lack of a magnetic field has allowed Venus to lose most of its hydrogen. I don't know who assumed only CO2 ice existed on Mars, but the estimates on liquid water and such were based on the available measurements of temperatures on Mars.


    Being difficult and costly don't alone make something worthwhile. As for the blue sky...it would be far easier to achieve inside a spacecraft or habitat than it would be to make Ganymede's sky blue. Even Mars, when the atmosphere is built to the depth needed to maintain Earthlike pressures in the weaker gravity, would likely have a white or orangish sky. If we're that unable to adapt to the lack of blue skies, we'll make them inside our habitats.

    I don't think you've looked very much at the costs and difficulties of terraforming...you don't even appear to understand the relatively simple issue of distance from the sun, let alone the investments required, timescales involved, and returns you can expect to achieve. And there's the natural resources that would be destroyed in even a failed attempt at establishing an environment that, while taking constant effort to maintain, would be only marginally habitable to humans. It's not just expensive and difficult, it's just a bad idea.
     
  21. Oct 19, 2010 #20

    sophiecentaur

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    Is terraforming an answer to anything?
     
  22. Oct 20, 2010 #21
    Mars had liquid water in the past(hint of a past thick atmosphere, Titan has less than half mars Gravity, .14 but has a monsterous atmosphere,redundancy). Mars also has evidence from the existence of ancient oceans, dried up river beds, and permafrost! Some scientists consider it to be in the "habital zone". I understand the what you mean by the difficulties but regarding how science is continually changing. There are many methods and theories to terraforming(thus there would be a variety of approaches to cost which may change). Yes it will take time as technology progresses. Today scientists are slower to say something is impossible considering the progress thats been made. (Bending radio waves around an object may be a possible prelude to bending light making an object appear invisible). Besides I understand this may be difficult. What did President Kennedy say before NASA landed on the moon? (8 years later!!!)"We choose to go to the moon in this decade and do the other things not because they are easy but because they are hard." Alot of NASA scientists are and have been Star Trek fans! The little portable communication device (cell phone) and other things came up from the imaginations of that generation of imaginative people as well as landing on the moon. By the way it is known that the Greenhouse gas of CO2 is important on Earth without it the planet retains less heat. If it weren't for greenhouse gases emitting from geologic activity on earth, the planet could freeze over(possible ice age). The atmosphere is thicker at the equator were it is warmer and thinner at the poles due to condensed colder gases. We know how to warm up a planet we're doing it now! All we have to do is make it convienient. If we succeed we learn how to make Earth's in the cosmos. If we fail we still learn from the data collected in the future to improve upon and use the knowledge gained for Earth's benefit. By the way, before the discoveries of water ice and other features existed on Mars, it was assumed that the polar ices were CO2 and no water existed which was applied to the general knowledge and in textbooks also before the discovery. (Mars is about 200 million miles from the sun est. half of the Earth's sunlight) The sunlight Jupiter gets about 19%(around 500 million miles from the sun) depending on the orbit. Analyzing the galilean moons in respect to their synchronous orbits and quick rotation around the massive Jupiter(88,650 miles) that most of the surface area should recieve sunlight in an odd fashion after emerging from behind jupiter from an eclypse. Though the days are longer they are not "solar days" as they revolve around jupiter, once again, synchronously. Titan indeed receives low solar energy that is why I didn't suggest it as a candidate. The logic I'm implying incudes a greenhouse gas 1,200 times more potent than CO2 hydrofluorocarbons to enhance the retaining of heat from attenuating solar energy. Atmosphere can be released from carbonate rocks and ices which mars and some of the galilean moons might have an overabundance of. Yes there are loopholes around these things as well as in physics. You are very knowledgeable in this topic. I'm impressed :D. I believe the word for this is "possible". What is one of NASA's goals? (to extend human presensce across the solar system). People may want to breathe, taste, and feel Mars without a space suit. Thats part of the appeal and could aid in space tourism in the future. I apologize for the lengthy explanation.
     
    Last edited: Oct 20, 2010
  23. Oct 20, 2010 #22
    In the case of humans pioneering and exploring the cosmos it can be extremely beneficial.
     
  24. Oct 20, 2010 #23
    Please explain Titan a moon of Saturn to me. It has gravity(.146 less than our moon) less than half that of Mars holding and atmosphere 50% thicker than Earth's? Which is mostly ice and rock in compostion with a diameter of 3,193 miles?
     
  25. Oct 20, 2010 #24
    Remember Ganymede synchronously(same side faces Jupiter) rotates as it revolves around Jupiter(it's not a solar day) As Ganymede emerges from it's Jovian eclypse there is sunlight. The dark side faces away from the sun but that changes in a weird fashion as it orbits illuminating much of the surface. The other Galilean moons may have a similar function. A scientist theorized about detonating numerous hydrogen bombs with heat higher than the surface of the sun spreading shockwaaves of heat along a great expanse melting ice and releasing greenhouse gases and other gases from carbonate rocks as well (on mars). The O2 can split from water vapor and fill the atmosphere bump around and form O3 (Ozone). Hopefully an end result may be a warmer thicker atmosphere global shallow oceans. Good question!
     
  26. Oct 20, 2010 #25
    Well, the gravity is almost identical to Titan's. Titan's atmosphere is thought to mimic earth's early atmosphere so knowing this and Titan's 50% thicker atmosphere, I believe the answer would be yes.
     
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