Space

[anoni]

I thought I might post something that lots of people enjoy and like to analyse. Space!

So my question for all of you is how do you think we could go about colonizing other planets and visiting other solar systems?
What about the limitations of space-travel? How has space travel been explained in movies, books and video games such as mass effect and star wars? and would their theories work in Real life? Do you think that if we did manage to go to other planets would we find life? what if we made livable areas actually in space? Etc etc

I'm gonna start things off with a fun fact, a human body can actually survive in space for more then 90 seconds! Our bodies can contain a large amount of body heat so the next-to-absolute zero temperature takes a while to actually hit us. Our bodies have enough strength to hold in our insides trying to escape due to the lack of pressure and our blood only boils from solar radiation at around two minutes of exposure.

Here are some sources:
http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970603.html
http://www.damninteresting.com/outer-space-exposure/
http://space.about.com/cs/basics/a/bodyvacuum1.htm

It's interesting to see how much movies have exaggerated the effects the human body has on space



PS: Also thought I might add... SPAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACE

[White Wolf Guardian]

For at least a few hundred years more, I really don't see the need to do something like this, but I'm sure someday we will try. I think however the only way we'd feel motivated enough to invent the means to move to other planets, is if and only when we had exhausted a great deal of planet resources and/or have overpopulated too much would we go further. I am for certain though the first planet to be colonized would be Mars.

Add carbon dioxide, make some bio-spheres, then slowly build up the planet to be livable by recreation of another atmosphere. I think even attempting to populate the Moon on the other hand would just be a bad idea. I believe the surface lacks the proper nourishment for any sort of plant life to prosper nor any source of water.

[Luggz]

For a start Terraforming would have to become a reality, it is believed Mars used to be a similar planet to what the Earth is now and might contain minerals/resources needed for hypothetical planet engineering.

To reach other solar systems would probably require a stepping stone approach. Moving further outward through our system. However the obvious drawbacks are that the majority of planets would be uninhabitable and are too far apart.

I'm a firm believer in other life forms. I'm not necessarily saying at a "developed" level but there must be at least some plant life out there.


White Wolf don't you think we are over populated?

[anoni]

There's an interesting hypothesis with overpopulation and that's the idea that when we around the 20,000,000,000 people mark people will die just as fast as being born, so it will balance out.

I don't think we can travel to other solar systems using a stepping stone approach, exiting our solar system is one thing but our solar system is so isolated, the nearest solar system is hundreds of billions of miles away. If we were to go to the stepping stone approach there would be a lot of going into deep space, seeing nothing, then coming back. I'm guessing a lot of people would lose interest in it and funding would probably seize.

  As for which planet to colonize, well mars is probably the safest bet, a couple of problems would obviously be the lack of oxygen and the temperature of mars which is very, very cold. Not to mention the solar radiation that goes onto the surface of mars. For small settlements, the moon might actually be better because it's closer, and we'd have to create an artificial environment on mars or the moon anyway. However for large colonization and settlements, mars would obviously be better then the moon. Also, the lack of gravity on the moon could also cause some problems in the long term. Mars also has low gravity, but I guess it isn't as bad.

[Aoren Deringer]

I figure that (if we ever have one) an extra-solar settlement would have to be on the nearest star (Proxima Centauri assuming that Nemesis doesn't exist) and would not be a planet. Theoretically we could put a large sattelite-colony in orbit around Proxima Centauri. We could even fuel it with materials harvested by objects such as meteors. In terms of water... Well, that's a problem that's not wholly unsolvable even today.
Also the moon could in theory support plant life, as it is very mineral-rich (thus the multiple proposed "lunar mining" programs)

[anoni]

Moon is mineral rich and has the necessary sunlight (if of course, you are on the bright side of the moon), though, solar radiation would be WAY too much for plant life unless we made an artificial bio-dome. Also, we'd need to bring soil and water with us.

I wonder if we can find some hydrogen-oxygen rich planets and then create artificial water

But I do agree with you about that a satellite colony might be a good choice. Problem is really gravity, but if we had a large enough space-station we could use rotation to create the artificial gravity, though of course, it would be the opposite (gravity going outwards), so might get a bit disorienting.

[legolyle]

I think there are many reasons why Humans could want to colonize other planets, but I think the only reason we will ever do it is for monetary gain, plain and simple. No single person will have the money to solve the problems of space travel. Or rather-no single person can build the stuff necessary-as the ideas to actually travel between stars wont cost that much in comparison.
 
 
 The two most realistic systems for space travel I’ve heard of thus far are: wormholes and cryo-sleep. No doubt there are many out there I haven't heard of.
Most video games, movies, and shows depict space travel as some form of FTL (faster than light) method. Maybe its not intentional-but they always seem to be "traveling" from mere hours, to weeks. Star wars was in fact FTL, using a system of classes of hyperdrive, while something like Halo used an alternate dimension (I think, not sure-they ripped a hole in space time), where they put the crew in cryo sleep for days/weeks.


In addition, legit FTL travel has to take into account the relativistic effects of traveling at that kind of speed. Which the movies rarely do xD
It's the more complicated side of FTL, but, pretty much, time travel results and causality can be violated. Which...yeah...you can then create a loop...and everything blows up.
That sort of tech, I think, is probably *not* likely to occur first. I mean, I'd be last to totally discount it, but the numbers involved are sort of crazy-acceleration and energy req'd being on the forefront. The energy required to accelerate a significant mass to super high velocity would probably be better put to use doing something else. Like, trying to rip a hole in space time xD


What do I know, I'm just a lowly engineering student, not even a grad yet, so take my opinion with a grain of salt


man, now you've got me reading physics >.<


As stated above, colonization likely won’t start unless the government(s) or businesses see a reason. Seeing as how governments would likely not see a very good reason to do it (They may one day), businesses are more likely to do it for monetary gain. However, they would need evidence that it would provide monetary gain. So, I think it likely for quite a while that we are going to have unmanned missions. Even when we develop a way to travel between bodies in a small time period, I believe it will be quite some time until we actually start to ‘migrate’ to other worlds.


That said, I wish I had been born about 800 years from now, maybe more

[anoni]

The biggest and most obvious complication of FTL speeds are the relativistic mass of the spacecraft. Which, when going the speed of light, would be infinite, and when going faster than the speed of light, would be greater than infinite mass, in which case, a greater than infinite force would need to be applied in order for the object to accelerate. This is obviously, impossible. Less obvious effects are the fact that time would actually be going backwards relative to an outside observer, so to them you'd never actually reach your destination and to you, you would reach your destination before you left. An even less obvious effect is the fact that you go into "negative space" where you are actually beyond infinitely thin relative to an outside observer. Going faster than the speed of light would mean that the universe to you would be more than infinitely thin and you would actually be bigger than the universe.

...trippy.

And yeah, there would have to be a good reason to colonize other planets, perhaps when/if globalization sets in completely we might actually have the resource to do something like that.

[legolyle]

so to them you'd never actually reach your destination and to you, you would reach your destination before you left.

and thus the loop xD it just doesn't make logical sense.

An even less obvious effect is the fact that you go into "negative space" where you are actually beyond infinitely thin relative to an outside observer. Going faster than the speed of light would mean that the universe to you would be more than infinitely thin and you would actually be bigger than the universe.

now, that's something I've never heard of, what is that based on? Got a wiki link?

[anoni]

This is based on the effect special relativity has on length, in which case, due to there being different relative times, the light at some parts would reach to you quicker then it would normally, which would cause a contraction in the object under the equation Lt = Lo x sqrt(1 - v^2/c^2) where Lt = relative length, Lo = original length, v =velocity and c = the speed of light.

So when the speed of light is reached the length actually appears as 0 or, actually, undefined, beyond the speed of light it gives an imaginary number (square rooting a negative).

My physics text book explains as follows.

As a consequence of perceiving time differently, observers in differing frames of reference also perceive length differently; that is, lengths that are parallel to the direction.

http://en.wikipedia.org/wiki/Length_contraction

have fun