Venus vs. Mars colonization

[Buster Charlie]

2 hours ago, fredinno said:

 

Well, if your reactor blows up, you're pretty much dead. I would still keep caution.

No argument there,  but the same is true with say, the jet/rocket your flying, the gas heater in your house, etc.

 

Huge difference between respecting a powerful tool, building it the best to avoid catastrophic  failure, and people who essentially say we can't even try to do anything that sounds scary. 

[fredinno]

5 hours ago, kStrout said:

First off, solar wind is not the main radiation concern, it's cosmic rays that are the problem, on a place like Mars you would need to live at least 5-10 meters down to prevent cancer over long periods of time, which kinda ruins the fun of "I live on another planet."

Secondly, the asteroid belt is not the only place space colonies could be built, they could be built in LEO (actually really nice because of free radiation shielding), around the moon, or if you really want to go to Mars, Phobos and Deimos have enough materials  to make space colonies easily exceeding the livable area of earth.

Yeah, and cosmic rays whould be blocked at least by 1/2 due to the planetary horizon below blocking the sky. Bonus points for having an atmosphere, or a weak regional magnetic field (both which provide more shielding.) And I don't see any problem with living underground- even if you needed sheilding, it's likely just as easy just to pour regolith over your colony to create a sheilded surface colony. 

Making space colonies exceeeding the livable area of earth is really difficult. Even a domed mars colony is almost certainly less complex.

[SargeRho]

5 hours ago, kStrout said:

First off, solar wind is not the main radiation concern, it's cosmic rays that are the problem, on a place like Mars you would need to live at least 5-10 meters down to prevent cancer over long periods of time, which kinda ruins the fun of "I live on another planet."

Electromagnetic fields. We can produce these, and I'm pretty sure i read something about a magnetic field generator being developed to help shield spacecraft. Put one of those on the ground, with redundant systems, etc. of course. And if it fails, you always can go into the underground radiation shelter while someone, or a robot, goes fix it.

[Bill Phil]

34 minutes ago, SargeRho said:

Electromagnetic fields. We can produce these, and I'm pretty sure i read something about a magnetic field generator being developed to help shield spacecraft. Put one of those on the ground, with redundant systems, etc. of course. And if it fails, you always can go into the underground radiation shelter while someone, or a robot, goes fix it.

Those usually act against particle radiation, though. 

For example:

In LEO, the ISS receives much more radiation than on the surface of the earth, and both locations are within the magnetic field. The magnetic field mostly traps/redirects charged particles, like the solar wind. This is why the van Allen belts exist.

1 hour ago, fredinno said:

Yeah, and cosmic rays whould be blocked at least by 1/2 due to the planetary horizon below blocking the sky. Bonus points for having an atmosphere, or a weak regional magnetic field (both which provide more shielding.) And I don't see any problem with living underground- even if you needed sheilding, it's likely just as easy just to pour regolith over your colony to create a sheilded surface colony. 

Making space colonies exceeeding the livable area of earth is really difficult. Even a domed mars colony is almost certainly less complex.

Only less complex in that it doesn't spin. It still suffers from almost every other problem, but you also need to expend more energy to put it there.

Not to say planetary colonies will never exist, but they're just not practical. If it was as easy as going to another continent, I could see it. But it's not.

[kStrout]

1 hour ago, SargeRho said:

Electromagnetic fields. We can produce these, and I'm pretty sure i read something about a magnetic field generator being developed to help shield spacecraft. Put one of those on the ground, with redundant systems, etc. of course. And if it fails, you always can go into the underground radiation shelter while someone, or a robot, goes fix it.

The problem with cosmic rays is that they are not very plentiful, but they are (relatively) massive particles moving very fast. You need planet sized magnetic fields to put them there. Also this arrangement you've described would work just as well in a space colony, without having to spend extra energy to put this equipment in the bottom of a gravity well. As Bill Phil pointed out, almost all problems orbital colonies face, surface colonies face the same issue, with the addition of being stuck at the bottom of a gravity well and trickier construction.

[HebaruSan]

How much energy would it take in an ideal case to smash Mars and Venus together at the Sun-Earth L3? Maybe we can make one viable colony if we combine them.

[Bill Phil]

20 minutes ago, HebaruSan said:

How much energy would it take in an ideal case to smash Mars and Venus together at the Sun-Earth L3? Maybe we can make one viable colony if we combine them.

Moving planets?

Too much.

[SargeRho]

1 hour ago, kStrout said:

The problem with cosmic rays is that they are not very plentiful, but they are (relatively) massive particles moving very fast. You need planet sized magnetic fields to put them there. Also this arrangement you've described would work just as well in a space colony, without having to spend extra energy to put this equipment in the bottom of a gravity well. As Bill Phil pointed out, almost all problems orbital colonies face, surface colonies face the same issue, with the addition of being stuck at the bottom of a gravity well and trickier construction.

How about Lava tubes, then? They exist on both Mars and the Moon. Seal them, pressurize them, and you have a nice living space. Surface habitats can simply be buried in Martian and Lunar dirt.

[fredinno]

5 hours ago, SargeRho said:

Electromagnetic fields. We can produce these, and I'm pretty sure i read something about a magnetic field generator being developed to help shield spacecraft. Put one of those on the ground, with redundant systems, etc. of course. And if it fails, you always can go into the underground radiation shelter while someone, or a robot, goes fix it.

Yeah, thoses are no good for cosmic rays.

2 hours ago, HebaruSan said:

How much energy would it take in an ideal case to smash Mars and Venus together at the Sun-Earth L3? Maybe we can make one viable colony if we combine them.

at Sun-Earth L3, they would evnetually collide with Earth due to gravitational instability anyways.So bad idea.

1 hour ago, SargeRho said:

How about Lava tubes, then? They exist on both Mars and the Moon. Seal them, pressurize them, and you have a nice living space. Surface habitats can simply be buried in Martian and Lunar dirt.

Those would severely limit where you can live.

[SargeRho]

19 minutes ago, fredinno said:

Those would severely limit where you can live.

True, however, for an initial settlement, these would be perfect. Later you can make your own tunnels more easily.

[kStrout]

Sure you can pressurize lava tubes and live in them, but 1. we don't know the effects of low gravity on developing children. 2. It's just as hard or harder than making and equivalent sized space colony, just now you're stuck at the bottom of a gravity well.

[peadar1987]

You're stuck at the bottom of a gravity well with all of the raw materials you will ever need though. Every gram of stuff for a space-based colony will have to be lifted off the ground. ISRU will absolutely not be a thing.

Edited February 29, 2016 by peadar1987

[Bill Phil]

2 hours ago, peadar1987 said:

You're stuck at the bottom of a gravity well with all of the raw materials you will ever need though. Every gram of stuff for a space-based colony will have to be lifted off the ground. ISRU will absolutely not be a thing.

Except that it's wasteful.

If you don't put yourself in a gravity well, it could potentially cost less energy per unit of resources mined than in a gravity well.

Also, ISRU has to be a thing for colonies to even work, at least to an extent.

[AngelLestat]

I made some tables that might help in this discussion, I hope you also help to correct or fill. I post them here:

 

On 24/2/2016 at 10:41 AM, Bill Phil said:

In Orbit it takes less energy to just spin to provide gravity. No reason for planets.

A better question is what can you achieve living on a planet. Nothing, really. It's hard to trade, and pretty much every economist agrees that trade is a key part to everyone getting rich. Why make it harder to trade for no reason?

Venus, Mars, or any planet can never be self sufficient unless you ship the things you need there. At least with our tech. But again, pure self sufficiency isn't a sustainable situation.

But orbital colonies will reach self sufficiency. They can move, and they can move to asteroids and mine them and stuff.

You can live..  is the whole point of colonization, I explain that you dont need to live of trade, you can have a successful economy and growth with zero trade.
Space colonies will be very expensive,  the difference in deltav to reach venus vs low orbit is very low, then once you have the same level of development in venus or mars than earth.. it will have more potential to growth than a ship which just mine asteroids.
If you move to the asteroid belt, your energy cost will rise a lot, and you are very far from earth to sent those minerals back.

On 24/2/2016 at 11:30 AM, kStrout said:

Ok, so you do have a point here, space colonies are not cheap. But they're not that expensive either. Think about it, Industry is going to precede colonization when it comes to space, and industry is going to set up on asteroids because it's easier to export to Earth. By the time communities get up there there will be tons of building resources in orbit. Most of the mass of a space colony comes from shielding anyway, which can just be slag, the useless stuff mining operations have to get rid of. It's not going to be more expensive per m^2 to make habitable land in a space colony, It might even be cheaper.

Why people will live up there?  I imagine that you have your asteroid in LEO, you can control all from earth.  Of course at begining it will be cheap to mine some asteroids, like heavy metals or just ice for fuel.
But I dont find any reason to have a big population living in a ship which purpose is just move "that big fat habitat mass" to an asteroid which is further from the sun (less energy), and what if that asteroid just has ice or heavy metals..  then you need at least 2 or 3 asteroids (at the same time)  to supply that big habitat?  but you need to produce products too, so you need to move all the extra industrial ships with you. 

On 24/2/2016 at 11:30 AM, kStrout said:

Exactly, planets work [citation: earth]. But just because they work does not mean they are the best option, and it definitely doesn't mean they are the only option. Who conquered the world? The cave-hopping cavemen, or the first humans that started making surface settlements?

Depending the time..  in one age cave hopping cavemen where the only ones who survive..   with our technology, planets seems a better target..   and if our tech increase..  then why deltav will be an issue??
How much "fuel" would spent a fusion ship like the avatar's valkyrie?

On 25/2/2016 at 10:45 AM, Buster Charlie said:

Haha, I love that though. An entire planet which humans cannot survive naturally due to lack of atmosphere,  lethal temperatures,  and don't forget high natural radiation....
And people are worried about a reactor failure.
It reminds me of hundreds of thousands of violent deaths and master destruction from a tsunami, being overshadowed by a comparatively benign nuclear reactor failure in japan. I bet all those people who died drowning wished they had to deal with a "disaster" involving radiation levels you'd experience flying from Japan to California. 

I suspect with all the hazards on Venus or mars, irradiation from a man made reactor is low on your list of worries.

Ask that to the 200000 people who had to abandon their home in japan, to the 200 billions spent in reactor decommissions (which put to japan for far in the number 1 country with more debt from the world)
Even if the radiation levels on some locations might not be so high in comparison with the max limit of nuclear workers..   it means anything?  no.. because nobody really know for certain the radiation issues in many of your life aspects like having children and the implications on their dna)... who will bought you the food that was made in a radioactive polluted area? 

Also.. you think it will be ok for some company or country just pollute the whole planet because they did not spent in extra care?
Venus on the other hand does no need nuclear..  they have gradient wind..  something much much better with no need for storage and with high powers densities. 

[fredinno]

12 minutes ago, AngelLestat said:

I made some tables that might help in this discussion, I hope you also help to correct or fill. I post them here:

 

You can live..  is the whole point of colonization, I explain that you dont need to live of trade, you can have a successful economy and growth with zero trade.
Space colonies will be very expensive,  the difference in deltav to reach venus vs low orbit is very low, then once you have the same level of development in venus or mars than earth.. it will have more potential to growth than a ship which just mine asteroids.
If you move to the asteroid belt, your energy cost will rise a lot, and you are very far from earth to sent those minerals back.

Why people will live up there?  I imagine that you have your asteroid in LEO, you can control all from earth.  Of course at begining it will be cheap to mine some asteroids, like heavy metals or just ice for fuel.
But I dont find any reason to have a big population living in a ship which purpose is just move "that big fat habitat mass" to an asteroid which is further from the sun (less energy), and what if that asteroid just has ice or heavy metals..  then you need at least 2 or 3 asteroids (at the same time)  to supply that big habitat?  but you need to produce products too, so you need to move all the extra industrial ships with you. 

Depending the time..  in one age cave hopping cavemen where the only ones who survive..   with our technology, planets seems a better target..   and if our tech increase..  then why deltav will be an issue??
How much "fuel" would spent a fusion ship like the avatar's valkyrie?

Ask that to the 200000 people who had to abandon their home in japan, to the 200 billions spent in reactor decommissions (which put to japan for far in the number 1 country with more debt from the world)
Even if the radiation levels on some locations might not be so high in comparison with the max limit of nuclear workers..   it means anything?  no.. because nobody really know for certain the radiation issues in many of your life aspects like having children and the implications on their dna)... who will bought you the food that was made in a radioactive polluted area? 

Also.. you think it will be ok for some company or country just pollute the whole planet because they did not spent in extra care?
Venus on the other hand does no need nuclear..  they have gradient wind..  something much much better with no need for storage and with high powers densities. 

Yeah, and 0-300 people died/will die from the accident.https://en.wikipedia.org/wiki/Fukushima_Daiichi_nuclear_disaster_casualties#Japanese_government_report

[Buster Charlie]

6 hours ago, AngelLestat said:

 

Please feel free to private message me if you wish to continue this but PLEASE DO NOT HIJACK VENUS OR MARS TO TALK ABOUT EARTH RELATED ATOMIC ENERGY!

 

Thank you!

Edited March 1, 2016 by Buster Charlie

[AngelLestat]

1 hour ago, Buster Charlie said:

Please feel free to private message me if you wish to continue this but PLEASE DO NOT HIJACK VENUS OR MARS TO TALK ABOUT EARTH RELATED ATOMIC ENERGY!

 

Thank you!

Are you kidding me?    that is exactly what you did with your previous message..  You said that the fukushima accident was all bluff... I disagree and you now said that I am trying to derail this topic?
I don't need to have that discussion again.. if you want to hear my opinion on the topic I invite you to use the search tool with related keywords.
But does not matter all the things that we can said..    you know that I am right..  you can not put a reactor in mars without worrying on the risks, and nobody will allow to a company or country to experiment with the planet unless all are agree and there is no pollution risk.
 

[Buster Charlie]

http://www.space.com/24731-mars-radiation-curiosity-rover.html

[kStrout]

9 hours ago, AngelLestat said:

Why people will live up there?  I imagine that you have your asteroid in LEO, you can control all from earth.  Of course at begining it will be cheap to mine some asteroids, like heavy metals or just ice for fuel.
But I dont find any reason to have a big population living in a ship which purpose is just move "that big fat habitat mass" to an asteroid which is further from the sun (less energy), and what if that asteroid just has ice or heavy metals..  then you need at least 2 or 3 asteroids (at the same time)  to supply that big habitat?  but you need to produce products too, so you need to move all the extra industrial ships with you.

Well you wouldn't move the entire colony to get materials, you would have mining setups on large asteroids that would produce material that could be sent to the build site by only dozens of m/s of DV. There are two big advantages of space colonies, customization, and transportation. Customization because every factor from the gravity to the air pressure to the terrain can be controlled, on planets that are not exactly like earth, we have to change the things we can, and accept the things we can't (gravity). Secondly, once in orbit you're halfway to anywhere, so why not just live there and already be halfway to anywhere you want to go?

[Blaarkies]

34 minutes ago, kStrout said:

Well you wouldn't move the entire colony to get materials, you would have mining setups on large asteroids that would produce material that could be sent to the build site by only dozens of m/s of DV. There are two big advantages of space colonies, customization, and transportation. Customization because every factor from the gravity to the air pressure to the terrain can be controlled, on planets that are not exactly like earth, we have to change the things we can, and accept the things we can't (gravity). Secondly, once in orbit you're halfway to anywhere, so why not just live there and already be halfway to anywhere you want to go?

The "halfway to anywhere" does not apply well to places outside low orbit, like somewhere in asteroid belt. It costs a lot of DV when burning in deep space(somewhere interplanetary) to get anywhere, just because you longer have Oberth on you side...but a space colony "near" a gravity is really a good idea

Escaping in retrograde from Luna orbit you can swing close by Earth with little DV, already having a trans-lunar orbit...it is a lot easier getting Earth escape velocity at that point.
Getting back from interplanetary voyages, you can exploit gravity assists from Luna.

[AngelLestat]

4 hours ago, Buster Charlie said:

http://www.space.com/24731-mars-radiation-curiosity-rover.html

??  what you want to show me?  the amount of radiation on mars surface?  I already know that..  an average is mentioned in this table that I did yesterday:

If you are mention the curiosity RTG power source..  that only generates 2kw thermal, the most common nuclear reactor on earth generates 3 gw thermal (1 million times more).
Now mars surface is 3,5 times lower than earth surface, its atmosphere is 204 times less massive, you can only count the dust mass that travels over the surface, because you dont have rain or plants to carry that radiation under the soil or to diluted..  earth also has an amount of water that might cover all earth surface with 1500m of depth.
That is a lot of mass compared to mars to dilute and reduce radiation issues. So I can not tell you with accuracy how many times worst is a nuclear accident in mars, but it will be very considerable even at the radiation levels that already has.
If the same dust is the source of that radiation, then it can be in the material you use to made products, or habitats, it can enter to your habitat or your lungs.
A radiation source stick to your skin, it becomes a real problem.

3 hours ago, kStrout said:

Well you wouldn't move the entire colony to get materials, you would have mining setups on large asteroids that would produce material that could be sent to the build site by only dozens of m/s of DV. There are two big advantages of space colonies, customization, and transportation. Customization because every factor from the gravity to the air pressure to the terrain can be controlled, on planets that are not exactly like earth, we have to change the things we can, and accept the things we can't (gravity). Secondly, once in orbit you're halfway to anywhere, so why not just live there and already be halfway to anywhere you want to go?

Someone may need that (low deltav movility) only if you have a venus popullation and a mars popullation, what is the point to have a lot of population on orbit?  Where they would go?  
You dont even need them there, because you said that you mine the asteroids with specialized machinery on the asteroid location... 
I understand that might be a niche for certain amount of people that might be convenient to live in LEO or moon orbit.
But if you want to sell products to earth popullation, it will cost you an extra to sent those down there..  you can sale products to those who wanna produce space applications..  is not a small case, but is not so bigger neither.

Edited March 1, 2016 by AngelLestat

[kStrout]

6 hours ago, AngelLestat said:

Someone may need that (low deltav movility) only if you have a venus popullation and a mars popullation, what is the point to have a lot of population on orbit?  Where they would go?  
You dont even need them there, because you said that you mine the asteroids with specialized machinery on the asteroid location... 
I understand that might be a niche for certain amount of people that might be convenient to live in LEO or moon orbit.
But if you want to sell products to earth popullation, it will cost you an extra to sent those down there..  you can sale products to those who wanna produce space applications..  is not a small case, but is not so bigger neither.

It's not a niche, think big picture, there is a highly limited amount of land area on any given planet, I forget the exact numbers but I think I once calculated that all the material in Phobos and Deimos would be enough to create space colonies with more surface area than all of earth, all custom, perfect land. And selling products to earth populations would be even more difficult by far if your colony was on another planet.

[Bill Phil]

8 hours ago, Blaarkies said:

The "halfway to anywhere" does not apply well to places outside low orbit, like somewhere in asteroid belt. It costs a lot of DV when burning in deep space(somewhere interplanetary) to get anywhere, just because you longer have Oberth on you side...but a space colony "near" a gravity is really a good idea

Escaping in retrograde from Luna orbit you can swing close by Earth with little DV, already having a trans-lunar orbit...it is a lot easier getting Earth escape velocity at that point.
Getting back from interplanetary voyages, you can exploit gravity assists from Luna.

EML-1 and 2 take very little Dv to get to most places.