In what year do you think humans will colonize the first planet outside of Earth?

[Hektor12]

once you have made enough O2 most of it is going to get recycled

Through recycling you get methane thus losing an important part of the material constantly. Im thinking about huge amounts and long run.

[Annihilus]

Through recycling you get methane thus losing an important part of the material constantly. Im thinking about huge amounts and long run.

recycling for the most part will be done by organisms that use CO2

[Hektor12]

recycling for the most part will be done by organisms that use CO2

I dont know but theres no 1:1 recycling, you always get side products that are useless and constantly lose a part of the recycled material.

[Annihilus]

I dont know but theres no 1:1 recycling, you always get side products that are useless and constantly lose a part of the recycled material.

Ever heard of a biosphere in a jar?

[Hektor12]

Ever heard of a biosphere in a jar?

Yes but i dont know how sustainable is that at much bigger scale.

[Ruggery]

I dont know but theres no 1:1 recycling, you always get side products that are useless and constantly lose a part of the recycled material.

How do you think they store oxygen in space bases and stations?

[Finnish Swede]

I do not believe humans will really colonize any planet in our solar system. Colleting minerals, and other ways using them? Definitely.


The big step will happen as humans will find the ways to reach the planets of other solar systems like Ross 128b (11 lightyears from us) ... orbits around the Ross 128 star.


The temperature is expected to be between -20c to +60c



Or Proxima Centauri D (just 4,2 light years from us) ... orbits around the Proxima Centauri star.



And there are many others....

None of us will be seeing that. I just hope humans would be wise enough so that some could in the future.

[Hektor12]

How do you think they store oxygen in space bases and stations?

They get it from water.

[Dick]

Once again, NEVER!

[alnortedelsur]

I agree, in the short term it will be Mars and some moons of the solar system, in the long term exoplanets when you can travel outside the solar system.

I didn't mention Europa (another Jupiter's moon), because there can be too much radiation in there. Out of the Jovian satellites, the closer to Jupiter, the more radiation you get from the Jupiter radiation belt. And Io (closer to Jupiter than Europe) is even much worse.

Regarding interstellar travel, the distances are too huge. Even the closest known exoplanets (Proxima Centauri B, and its companion Proxima C), which are like 4 light years away, are still unreachable with the current technology. Even if 4 light years might sound like relatively close for astronomical standards, is still such a huge distance that at the speed of several kilometers per second of the Voyager space proves (which is the fastest thing that humans have ever built) they would still last tens of thousands of years to travel that distance.

The only two options are multi generational travels or travel at a decent fraction of light speed. In the scenario of multi generational travels, assuming that they travel at a conventional speed (lets say, like the Voyager probes or a bit faster) all the human beings that stay on earth won't obviously be alive that long as to witness even when they reach the closest planetary system (and let alone other farther away planetary systems), since they would take multiple generations to get there. No to mention that it would take many decades to build such a spacecraft capable of traveling those huge interstellar distances, even if they were to travel at "conventional" speeds.

And the second scenario of building some spacecraft that travels to lets say half the speed of light, or lets say 25% the speed of light, even if they would theoretically reach the stars within a reasonably scale of the human life scale (including those on earth), it has its serious challenges: firstly that's a technological challenge that we don't know how long it would take to develop, maybe many decades or even centuries, and secondly, there are serious doubts of how practicable it would be to accomplish that goal. Once I read that one of the big challenges of traveling at speeds close to the speed of light (even if it's only, lets say 25% the speed of light) is that the interstellar void is not that empty as it seems to be, but has some scattered atoms, that despite their "relatively low concentration" at those huge speeds we are talking about, they would become a lethal danger for the hypothetical crew members, since the spacecraft would drive at those huge speeds against those scattered atoms, that at those huge speeds they wouldn't be felt by the spacecraft and its crew like being scattered any more, since they would impact millions of them in matter of seconds, creating a lethal ionizing radiation effect on the spacecraft and their crew members.That without mentioning the cosmic rays, and other dangers and the interstellar dust that would also erosion the spacecraft at those huge speeds. It would be a very big challenge to figure out how to travel at those speeds without being killed by such lethal radiation, and even the spacecraft getting disintegrated.