Space combat, travel, living...

[bobthedinosaur]

FTL is ludicrous.
Some more feasible methods of movement I can see is
http://en.wikipedia.org/wiki/Beam-powered_propulsion
but coupled with mass drivers, or space borne rail cannons, to get a nice starting velocity. Now just how to slow down in time with out de-accelerating too early and prolonging the journey.

Space elevators and or a space rail would help building any large scale orbital projects greatly and would cut down on costs and time.

[Teutooni]

Space elevators ... would cut down on costs and time.

Hmm, what's the tallest building to date? Less than 1km tall anyway. A space elevator would probably have to be over 36 000km tall to reach geosynchronous orbit, plus counterweight. How much would that cost?

[HeavyLancer]

Well, we could build a space fountain with today's materials. It's an actively supported structure that uses pellets shot through a giant magnetic loop that runs for the height of the tower to give it enough inertia to resist falling over. This magnetic loop system could also fling cargo and passengers through it as well.

The structure would need a big, reliable power supply, some interesting control mechanisms to maintain the velocity of the pellets and a lot of funding. It is physically possible though, and doesn't actually have to extend to geosynchronous orbit either - just getting to LEO is fine and have a lower payback time. Look at the wikipedia page for more information: http://en.wikipedia.org/wiki/Space_fountain

[Gota]

With advances in material engineering a space elevator is a much more real prospect.
Before it was impossible cause all materials were to heavy to use,the system would have collapsed on itself.
ATM it is very energy expensive to get out of orbit because you need to also lift huge amounts of the fuel components with you.

[HeavyLancer]

With advances in material engineering a space elevator is a much more real prospect.
Before it was impossible cause all materials were to heavy to use,the system would have collapsed on itself.

A space elevator would still require exotic nanomaterials like carbon nanotubes, manufactured at a massive scale. The other issue is the size - getting out to geosynchronous orbit is a huge leap, as others have said.
We really only need to get to LEO for big fuel savings, and from there we can use old-fashioned chemical rockets or perhaps VASIMIR engines to get to other places. A space fountain would be cheaper for that.

This biggest issue at the moment for both is capital raising, as both are huge projects that only the governments of highly-developed economies could really afford. The science is sound for both a space fountain and a space elevator, we just need a lot of materials science and structural engineering work to figure out the details. Then we have to build it

[Licho]

Taste some plasma!
http://www.youtube.com/watch?v=4zSou_r- ... 1&index=55

It should fly to ISS next year.

[Neddie]

With advances in material engineering a space elevator is a much more real prospect.
Before it was impossible cause all materials were to heavy to use,the system would have collapsed on itself.

A space elevator would still require exotic nanomaterials like carbon nanotubes, manufactured at a massive scale. The other issue is the size - getting out to geosynchronous orbit is a huge leap, as others have said.
We really only need to get to LEO for big fuel savings, and from there we can use old-fashioned chemical rockets or perhaps VASIMIR engines to get to other places. A space fountain would be cheaper for that.

This biggest issue at the moment for both is capital raising, as both are huge projects that only the governments of highly-developed economies could really afford. The science is sound for both a space fountain and a space elevator, we just need a lot of materials science and structural engineering work to figure out the details. Then we have to build it

And then we have to make it worth the investment in a real sense, not merely an "economic" sense. That would be obtaining and harnessing equivalent resources as a result, using the new environment to make significant and tangible advances in healthcare, etcetera.

[bobthedinosaur]

Sell mars, sell the moon. Lots of resources to rape, but you have to wait until they are considered rare on earth. You can send prisoners to mars, and the religiously persecuted. Make them live on a colony where they have to work to pay back their passage.

I would imagine if bio engineering doesn't kill us all off very quickly from a bad bio weapon, that it would be key to a terra forming process, or at least for hostile environment colonies.


The weaponization of space, with out nuclear missiles, could also be a reason for developed countries to throw money at projects like space elevators and rail/ loop launchers. I mean think how hard it is to shoot down a space borne laser or emp device. Especially since China has invented a single missile (stealth cruise missile I believe) that makes all the U.S. expensive nuclear powered aircraft carriers obsolete. Think about supreme diplomacy, control the free market from space!

[Licho]

I doubt it will ever be economical to transfer raw resources between planets..

We have all elements here and you wont just lose atoms, you can always recycle them or extract from places with low concentration.

If your resource is energy source, then it better be very rich, or transferring it wont pay energetically.
Like even if is most concetrated energy source currently used - uranium - sending it from Jupiter to Earth does not pay up energetically! It would take more energy to send it to Earth than energy contained in it

As for sending prisoners - ugh.. for that society has to be obscenely rich beyond our wildest imagination.

[Gota]

As for sending prisoners

Would be economical if you fly them into the sun.

[TradeMark]

sending prisoners to mars? isnt there a movie about such?

[HeavyLancer]

As for sending prisoners

Hey, the last time they found a piece of unexplored land the British sent prisoners. Cheap labour that has no rights is good for that sort of thing. However, given that a colonisation mission to Mars or Lunar will require a lot of life support infrastructure and very cohesive societies to start off with, establishing a prison colony is a much less worthwhile idea. Look at what happened in The Moon Is A Harsh Mistress.

As for resources, about the only thing we don't have lots of here on Earth that we could feasibly get from space are elements like Iridium and Helium-3. Lunar craters could have a bit of Iridium in them from asteroid impacts, plus the Helium-3 in Lunar regolith from the solar wind.

[TradeMark]

it'll be cheaper to build robots than send humen everywhere with tons of food etc

[Licho]

Regarding Helium-3 - why going to Moon for it? There is still lots of fissionables around - U238, Thorium.
And first fusion reactors like ITER will be cheaper Deuterium-Tritium with Tritium breeding capability from Lithium. So there is no need for He-3 ..


As for humans in space - depends on the task. Humans are the ultimate self-replicating intelligent machines. For maintenance of complex machinery its best to have them around!

[Panda]

sending prisoners to mars? isnt there a movie about such?

"Pitch Black" involved sending prisoners to desolate places. I liked that move because it was cool and it had Vin Diesel as the main character in it. Vin Diesel also did the voice for the robot in "The Iron Giant".

[Gota]

Pitch black was cool though not very demanding sci-fi wise.

[Panda]

I liked the sequel, "Chronicles of Riddick" too. It was awesome how he defeated the Necromongers and took over their empire. I thought that it made for a great sci film.

[Gota]

I liked the sequel, "Chronicles of Riddick" too. It was awesome how he defeated the Necromongers and took over their empire. I thought that it made for a great sci film.

aha...now that was a retarded movie...
pitch black wasnt very demanding but riddick was practically giving itself for free intelligence wise.
riddick was dumb even for a softcore action-scifi movie.

[bobthedinosaur]

It would probably be more energy efficient to neutron bombard current materials to make into fuels than it would to mine it and send it back. The step out of the solar system doesn't seem likely with out the step into the solar system, which doesn't seem likely. So interests will probably focus inward, and we will all die where we were born.

[HeavyLancer]

Regarding Helium-3 - why going to Moon for it? There is still lots of fissionables around - U238, Thorium.
And first fusion reactors like ITER will be cheaper Deuterium-Tritium with Tritium breeding capability from Lithium. So there is no need for He-3 ..

I agree on Thorium and U-238, they are much better fuel sources for terrestrial generation. The thing about He-3 is that it's a really good fuel for rockets, as it requires no breeding and is quite energy-dense. This is why the moon is a good idea for a 'stepping stone' to other planets - you can put a big mass driver, He-3 mining station and an automated spacecraft factory and you're set for colonising the rest of the system.

The only issue with it is that it still requires a big delta-V, so if it was simply used as a stopping point for a spacecraft from Earth it would be pointless. Factor in in-situ resource utilisation and a lunar cycler and you have some benefits though.