Not a bad idea in general though I'm pretty sure it would be easier to live on Mars (in domes) than to build "space cities".
Not really let's say you want to colonize Mars there are issues raw resources might not be there mining for iron there is expensive when sending it into space, a space elevator but meteors are an issue due to a thin atmosphere and rockets must beat gravity plus carry iron ore I don't think so. And automation as in robots might limit the need for many humans. A space community on say fifty stations might specialize exports from gathering water in Saturns rings to mining ore in asteroids to excess food and manufacturing or entertainment plus could be given propulsion to move many into space so 100 Arks in fleets could move to say 5 stars and start production. Each should be self-sustaining for 100 shots to spare the species also. And they could supply terrestrial colonies. And it limits the issues of gravity shipping 5000 tons of or by simple hauling freighter in space without gravity a big issue might be practical to reach Earth making mining them the best option..
The best humans can ever do is conquer our near side of the Milky Way. That may take a few thousand years but its not far off
70% of C is probably on the high side. There are a couple of really good (scientifically accurate) internet sites I could refer you to that delve into the ins out outs of space travel including interstellar travel. The presentations I have seen limit travel velocity to the 10-20%C range due to issues around shielding the crews from radiation and dust during transit which become significant risk factors the faster you travel. Detecting approaching threats and intercepting them at relativistic speeds seems to be almost as big a technical challenge as getting to those speeds in the first place. But the really big issue is that as far as planets it appears at this stage that there are unlikely to be any habitable worlds within hundreds of light years of Earth. That's just based on observations to date and the rate our remote sensor technology is improving we will probably be able to see potentially inhabitable planets long before we ever develop the means of traveling to one. The good news is you don't really need habitable planets (or even terraformable ones) - virtually any star system will do so long as it has exploitable asteroid and comet fields etc. If as seems likely to me anyway humans master the art of building large scale structures in space in tandem with interstellar space craft (seems to me you need the former to build the latter) then you don't really need planets. You can send out ships to any system you want within close range that has the desired supply of metals, volatile gases and other elements (and there are heaps of those close by). All the ship needs to do then is take along the equipment it needs to 'bootstrap' space based mining, processing and construction projects upon arrival. When it arrives it has all the building materials it needs for the construction of large (read huge) rotating habitats. You could even use Von Neumann style robotics to kick start the whole project along with long range supervision and direction from Earth. No humans required until the place is at least partially ready for habitation.
While colonizing Mars or even the moon seems to many to be a jump in the right direction, there are a huge number of problems we’ve yet to solve. Aside from the obvious challenges, radiation, cost, transporting necessary living supplies there are simple practical matters such as being able to escape and return in the face of life emergencies, effects of social group isolation on colonials, local governance vs remote governance (even interest ownership), resource management, health management, waste management, critical infrastructure failure response and support, developing a self sustaining food and water supply, oxygen mining, etc. Whether a colony in long transit to other star systems or a colony on the moon, we haven’t yet succeeded in anticipating building a self contained ecosystem that would be needed for colonization independent a critical supply link. Both experiments to test this prospect, Biosphere I and II failed, and not for obvious reasons. Then too, humans are a product of adaptions to the earth’s environment over hundreds of thousands of years. I suspect early attempts at colonization of the moon or Mars will have a high mortality rate, including a high potential for catastrophic failure. I note, in many attempts of colonization of the new world, a place with similar and familiar means for survival resulted in loses of entire colonies. Signing on to such a space adventure is likely a suicide mission. While many suggest we need to look to space for human survival, I would suggest we look to the sea. The tech to exploit the sea would be similar in nature to space, but building and testing the tech on this plant (robotics, self sustaining bio environments, waste management, etc) before moving to space would be significantly less costly and controllable than doing it millions of miles from here. We have half a planet here, one we are better adapted to already, that lies open at our feet, far more promising than off world. For those thinking we’ve already screwed the pooch here environmentally, if we can’t sort it here with all the advantages we have here, how would we figure any better potential in a new world that from the get go have far greater challenges that sorting out our problems here? Now think about interstellar travel’s challenges.
Space station living has many benefits above planetary colonization from gravity manipulation and space vehicle use to resource management/procurement and population health. Once the shielding issues are resolved (they will be soon) it should be a no brainer. Using Asteroids as factories will be very important in the near future.
One of my favorite YouTube sites. As for the Joe's conclusion's I think colonizing Mars is a massive, costly generational project that could not be done piece meal by small groups of explorers/colonists. It's something all the nations of Earth (or an organization representing them) would have to put together after 100 years plus of study and technological development. This doesn't mean we can't send missions there in the short term BTW just that we can't turn those missions into a serious colonization effort, any more than the Apollo missions, if they had continued would have lead to immediate full scale colonization of the Moon. You survey, research, test, re-model and if you are lucky after decades of work and remote-robotic preparation (if you still think it is worth the effort) you start with large numbers of colonists, backed up by massive capital investment.
This all makes it clear that there are two distinct activities relatig to space. One is sciece. There is no science objective that can be done more efficiently with humans in space. Space science is a totally separate activity. The other is humans in space. There is a lot of science required to figure out how to do this, but that science is fundamentally oriented to how to keep humans alive in such an environment - not with learning anything about our solar system, galaxy or universe. Given that we're not going to have a human colony off Earth for any real reason for a very long time (since it would be hugely expensive and there isn't any known need for that) we need to keep these efforts separate - including funding. So far, NASA has been giving this totally political objective regarding the moon plus totally unreasonable deadlines, but has not been given a budget that would allow success. What we're doing today is far more expensive simply because of the deadline requirements. imho, our science budget is at great risk of being destroyed by pointless efforts on human missions. And, decimating our space science just to briefly land some humans on the moon would be an imense tragedy for the science mission NASA has been successfullly carrynig out.
We can probably do something like that, at about the time we can build a Dyson Sphere. In other words, never.
How? So far, almost all discovered are impossible for humans to survive on. Crushing gravity, insane levels of radiation, extremes of hot and cold, we have yet to find a single planet that humans can survive on. Oh, and it is already way past "hundreds". At this point, we have already discovered over 4,100 exoplanets. And not a single one of them capable of supporting human life.
They don’t know that !! Many of these planets : have only been found and not yet studied due to distance and lack of technology
There is also the very simple fact that if there were Earth sized planets out there we do not have the ability to find them yet....we have guessed at a few, but that's it.
Well the thing is there is a world of difference between "Earth sized" and "Earth like". Venus is Earth sized but the environment there is hellish at best.
They have been well studied, and they can tell a lot about them. Mass, size, distance from their sun, speed of revolution, all of that is easily detectable. Gliese 180 B and C have masses between 6 and 8 times that of Earth. And they have orbital periods of 17-24 days. No way is either of them habitable. And both were discovered this year. Just by looking at the orbit and mass most exoplanets are immediately dismissed. And there is a 180 D, but it is a gas giant, so immediately dismissed. And yes, we can even find planets smaller than the Earth. [URL]https://en.wikipedia.org/wiki/Kepler-37b#/media/File:A_Moon-size_Line_Up.jpg[/URL][/imh] Kepler 37B was discovered over 7 years ago. It is over 209 light years away, and is only slightly larger than our Moon. But as it's surface temperature is roughly that of the sun, and has an orbital period of around 13 days. Once again, in no way habitable. We have found many that are earth sized, from Proxima Centari B to TRAPPIST 1E-1G. Why is it so hard for people to even bother to do research before making such claims?
Well, I think the point is that we're not doing a great job of finding Earth-like planets yet. I suspect that the EU missions will be a big help in studying what we've found, and I'll bet our pace of finding exoplanets will increase. Isn't it the case that the Earth sized planets we've found tend to be around red stars - thus not being good candidates for finding life due to red star behavior?
Most have been found in multiple star systems but they can rarely detect Earth like ones in SIZE due to technology problems. Most have been super large Earths. There are thousands of similar size Earths but better technologies in the upcoming decades will find them
To actually get there?? That will be future generations of thousands of years. Not going to happen this century lol
DEAR ALL It isn't just about "human survival" but also the biome humans require. Gut bacteria. Skin bacteria. And environmental microbes to keep our immune system tuned up. Wherever we go we must take our microbial friends with us. How will that effect "the natives"? -------------------------------------------------------------- Propulsion: I seem to remember a Heinlein book that involved "Instantainaity" Don't be constrained by Relativity. Over come it! Moi Colonize
We're going to have to take just about everything we need with us to anywhere we're likely to go off Earth this century. Mars is designed to kill us, with even the soil poisonous. It's fine to see The Martian try to grow potatoes for 1 in the crap from his entire crew, but nothing he used was local, his space suit was entirely inadequate for life, and no place he stayed would have protected him from the radiation. And, from the start there was no point to that mission that required a human presence. Science fiction is WAY ahead of reality.
I am sure one of the planets is filled with Dinosaurs ! May have developed just like Earth but 100 million years after
That would be Earthshattering news! So cool. It's really hard to believe that this universe has only us. Even if one believes in a god as per Christianity, why would he prevent all but one such experiment?
