stargazer777 - 4/6/2007 11:46 AMIt wouldn't be possible on the Moons themselves...
Marcus - 4/6/2007 3:34 PMQuotestargazer777 - 4/6/2007 11:46 AMIt wouldn't be possible on the Moons themselves... Why not?
lambda0 - 4/6/2007 7:28 AMAccording to Landis (NASA), the best place is ...Venus !At 50 km altitude :- Atmospheric pressure is 1 bar- Temperature between 0° and 50°C- Plenty of solar energy but protection against the most dangerous radiations by the atmosphere- As the atmosphere is composed of CO2, a quite heavy gase, a balloon filed of oxygen and nitrogen would be in equilibrium, and a 1 or 2 km diameter balloon would easily carry a small city- Due to the rotation of the atmosphere, and by controling the latitude, it is possible to reproduce a day/night cycle similar to Earth- The atmosphere contains oxygen, carbon, sulfur, in fact many of the elements necessary for lifeAt first sight, Venus seems to be a very hostile place (500°C on the surface, P=100 atmosphere), unless this thick atmosphere is considered as an ocean : Earth is also not so pleasant at 10000 m under the level of the sea.In fact, Venus may have many advantages compared to Mars...
stargazer777 - 4/6/2007 11:56 AM"Security"? At least Earth has an atmosphere to weed out lots of space debris. And as for use as an interstellar vehicle, doesn't the craft require sunlight for crop growth? If you read the heading on the thread, it says "Other than Earth, where is the best place to live?" I think that excludes Earth from consideration, don't you? Besides, none of the habitable alternative locations -- has a significant atmosphere.
"Security"? At least Earth has an atmosphere to weed out lots of space debris. And as for use as an interstellar vehicle, doesn't the craft require sunlight for crop growth?
meiza - 4/6/2007 6:58 PMWhat about hydrogen? There is potentially some amounts of hydrogen on mars.
Your right. Let me rephrase. I was assuming the Saturn's moons posed the same radiation problems that exist for the Jovian moons. I was incorrect. Saturn's 59 moons orbit mostly beyond the radiation belts of Saturn. However, that does not change the extremely difficult & dangerous environment we will encounter on those moons. For example, several contributors to this thread mentioned Titan. Titan has an atmosphere 1.5 more dense than Earth's atmosphere 98.4% nitrogen 1.6% methane with an estimated surface temperature of minus 289 degrees F with ethane or methane clouds and methane rain. This is an almost unimaginably hostile environment for humans. One that would surely leave any potential settlers dreaming of an airless moon or planetoid. However, if you want to chance it, be my guest. Among the 59 moons of Saturn, I imagine that there are some moons that are no more hostile than our own moon. My principal point remains correct though. A space borne habitat would be a far better alternative.
http://solarsystem.jpl.nasa.gov/planets/profile.cfm?Object=Saturn&Display=Moons
http://solarsystem.jpl.nasa.gov/planets/profile.cfm?Object=Sat_Titan
Of course I read the heading. My comparison was an aside that referred to your statement, "They offer earth type gravity, an earth like environment ...".
I'll add that with a planet or moon, for any point on the surface, you are protected from roughly half of the incoming trajectories because of the planet you are standing on that gets in the way.
Although I had seen these habitats as among the most far-fetched of space colonization pipe dreams, Bigelow's efforts have inspired me to think a little more open-minded. I still wouldn't want to live in one, should I live to be 969 years old.
stargazer777 - 4/6/2007 9:47 PMTell it to the dinosaurs.
the main problem with space habitats are ressources availability, there's nothing in orbit nothing at all, whereas on a planetary surface you have a rich solid ground under your feet, you have basically the whole planet (or moon) available to make oxygen, water, rocket fuel, construction materials, ...
the availability of vast amounts of readily available ressources significantly reduces the complexity, cost and risk of a colony. no need to ship anything from the earth, maybe some high tech components and medicine at the begining but that's it. and no need for a 100% efficient closed loop life support system if you can extract oxygen and water from the planet's surface/atmosphere. it's also easier to work inside a gravity field than in microgravity.
all those factors contribute to making a planetary colony more practical than a space habitat, thus they are likely to appear sooner and in greater numbers. if the latter even ever appears at all.
Actually Mong, I think you are wrong on that. You just have to expand your vision a bit. There are enormous -- almost unlimited -- amounts of ice and minerals of all types available on the countless asteroids in the asteroid belt and the "trojans" (not the condoms) trapped in Lagrange points by Jupiter, Saturn and the other gas & ice giants. Ultimately these will prove to be far easier to mine and consume than most planetary resources and are perfect for sustaining the space borne civilization I am describing. I didn't even mention the immense resources that will be available in the Kuiper Belt.
Beyond this, my saying that I think we are unlikely to place large colonies on extremely hostile planets and moons doesn't mean we cannot or will not mine them or explore or exploit them. I fully anticipate with tele-robotics and the far more advanced technologies we will have when we finally get out that far, we will be able to explore and exploit these worlds with limited human presence on the surface of those planets. Humans will have better things to do than freeze their buns off in an intensely hostile environment. I am not saying just do it from Earth -- I feel certain we must and will expand out as a people. I am saying that -- just like current deep ocean exploration -- most can and will be done robotically by people who reside somewhere else. And I think that somewhere else may well be the space habitats predicted by O'Neill.
http://en.wikipedia.org/wiki/Trojan_%28astronomy%29
http://space.newscientist.com/article.ns?id=dn8663
http://space.newscientist.com/article.ns?id=dn9340&print=true
stargazer777 - 6/6/2007 6:47 AM There are enormous -- almost unlimited -- amounts of ice and minerals of all types available on the countless asteroids in the asteroid belt and the "trojans" (not the condoms) trapped in Lagrange points by Jupiter, Saturn and the other gas & ice giants.
There are enormous -- almost unlimited -- amounts of ice and minerals of all types available on the countless asteroids in the asteroid belt and the "trojans" (not the condoms) trapped in Lagrange points by Jupiter, Saturn and the other gas & ice giants.
stargazer777 - 6/6/2007 6:47 AMUltimately these will prove to be far easier to mine and consume than most planetary resources and are perfect for sustaining the space borne civilization I am describing
lambda0 - 4/6/2007 8:28 AMAccording to Landis (NASA), the best place is ...Venus !At 50 km altitude :- Atmospheric pressure is 1 bar- Temperature between 0° and 50°C- Plenty of solar energy but protection against the most dangerous radiations by the atmosphere- As the atmosphere is composed of CO2, a quite heavy gase, a balloon filed of oxygen and nitrogen would be in equilibrium, and a 1 or 2 km diameter balloon would easily carry a small city- Due to the rotation of the atmosphere, and by controling the latitude, it is possible to reproduce a day/night cycle similar to Earth- The atmosphere contains oxygen, carbon, sulfur, in fact many of the elements necessary for lifeAt first sight, Venus seems to be a very hostile place (500°C on the surface, P=100 atmosphere), unless this thick atmosphere is considered as an ocean : Earth is also not so pleasant at 10000 m under the level of the sea.In fact, Venus may have many advantages compared to Mars...