Quote from: Andrew_W on 08/20/2011 01:35 amI'd be happy to send you to Mars Mick, but I'll at least need some indication that there's a possibility of untold mineral wealth before we put feet on the ground, even if Mars is littered with gold, even at it's heady price these days, we probably wouldn't cover the costs. We need something there that cannot be obtained on Earth at a lower cost, anything spring to mind?A resource that can be found on Mars that cannot be obtained on Earth at a lower costs: land that does not belong to any government, and is safe from sovereign intervention.As for the need for this "resource":A week ago I heard about some millionaires giving money to a group planing to found an independent libertarian floating island society. (Insert Andrew Ryan joke here) And if one of these "plans" has surfaced to my attention un-looked for, there must be many groups that wish to found their own society according to their own rules, and could take advantage of this resource Mars has to offer.
I'd be happy to send you to Mars Mick, but I'll at least need some indication that there's a possibility of untold mineral wealth before we put feet on the ground, even if Mars is littered with gold, even at it's heady price these days, we probably wouldn't cover the costs. We need something there that cannot be obtained on Earth at a lower cost, anything spring to mind?
Quote from: Andrew_W on 08/20/2011 01:35 amI'd be happy to send you to Mars Mick, but I'll at least need some indication that there's a possibility of untold mineral wealth before we put feet on the ground, even if Mars is littered with gold, even at it's heady price these days, we probably wouldn't cover the costs. We need something there that cannot be obtained on Earth at a lower cost, anything spring to mind?Peace and quiet springs to mind.Back to the OP. If "Building" means the construction of infrastructure then you cannot beat a planetary surface for the sole fact that the human species evolved and grew in gravity. That is what we know and live with every day. If, on the other hand, you mean growth and profitability then I think that would depend on the type of business being "Built ".Mick.
Quote from: MickQ on 08/20/2011 02:19 amQuote from: Andrew_W on 08/20/2011 01:35 amI'd be happy to send you to Mars Mick, but I'll at least need some indication that there's a possibility of untold mineral wealth before we put feet on the ground, even if Mars is littered with gold, even at it's heady price these days, we probably wouldn't cover the costs. We need something there that cannot be obtained on Earth at a lower cost, anything spring to mind?Peace and quiet springs to mind.Back to the OP. If "Building" means the construction of infrastructure then you cannot beat a planetary surface for the sole fact that the human species evolved and grew in gravity. That is what we know and live with every day. If, on the other hand, you mean growth and profitability then I think that would depend on the type of business being "Built ".Mick.Mick, I think natural gravity sucks! Far better off with the artificial gravity of a rotating habitat, have it as weak or strong as you like. Heck, you can even have a lower gravity in the attic while you have higher gravity in the basement, or have it lower in the morning and higher at night. Whatever rocks your boat!
The problem is, you'll still need to build industry on planetary surfaces, unless you can figure out a way to convert solar energy into matter....Thus, you're not gaining anything by moving your industry off the surface. Since space transportation is so expensive, it doesn't make sense to ship unrefined raw materials. Therefore, you're stuck with industry on planetary surfaces.
Quote from: Warren Platts on 08/20/2011 04:13 pmThe problem is, you'll still need to build industry on planetary surfaces, unless you can figure out a way to convert solar energy into matter....Thus, you're not gaining anything by moving your industry off the surface. Since space transportation is so expensive, it doesn't make sense to ship unrefined raw materials. Therefore, you're stuck with industry on planetary surfaces.It will always be most efficient to have refine raw materials as close to their source as possible. If one is getting a resource on Mars then it makes sense to refine it there. However the same goes for asteroids. Asteroids have many heavy elements in far greater abundance than planet surfaces. Iridium for example is 1000 times more prevalent in asteroids than it is on Earth. Gold, Uranium, and etc are likely going to come from asteroids.
However the thing is that mining and refining machines do not necessarily require gravity, whereas people do.
There's no evidence whatsoever that gold and uranium etc. are likely going to be found in higher concentrations than the Earth's or Moon's or Mars' crusts.
Quote from: DarkenedOne on 08/20/2011 06:44 pmHowever the thing is that mining and refining machines do not necessarily require gravity, whereas people do. Yes, they do. For transport (to stay in buckets or conveyers) or for settling
Planetary surfaces like Mars, definitely. You have a huge amount of resources available (tons and tons of free metal just within walking distance of any spot), you have an atmosphere that takes care of radiation shielding for you plus easy ISRU anywhere on the planet, you have frozen water, you have regolith that is rounded by aeolian processes instead of resembling broken glass (and thus can serve as a good growing medium, etc), the atmospheric pressure can be increased to high enough to not require pressure suits by increasing the surface temperature slightly through sprinkling carbon black powder strategically over the surface (the higher pressure also allowing liquid water and maybe even plants to grow on the surface, possibly), etc.All at rest with respect to you, as opposed to moving in different directions at different delta-vs.
A week ago I heard about some millionaires giving money to a group planing to found an independent libertarian floating island society.
There are only 2 ways to settle the gravity question. One is build a test station and spin up to your required G level and the other is put feet on Mars.
Quote from: Warren Platts on 08/20/2011 07:28 pmThere's no evidence whatsoever that gold and uranium etc. are likely going to be found in higher concentrations than the Earth's or Moon's or Mars' crusts.I thought is had been established through examining meteorites that some asteroids do have exceptionally high concentrations of these elements.
Quote from: DarkenedOne on 08/20/2011 06:44 pmHowever the same goes for asteroids. Asteroids have many heavy elements in far greater abundance than planet surfaces. Iridium for example is 1000 times more prevalent in asteroids than it is on Earth. Gold, Uranium, and etc are likely going to come from asteroids.There's no evidence whatsoever that gold and uranium etc. are likely going to be found in higher concentrations than the Earth's or Moon's or Mars' crusts.
However the same goes for asteroids. Asteroids have many heavy elements in far greater abundance than planet surfaces. Iridium for example is 1000 times more prevalent in asteroids than it is on Earth. Gold, Uranium, and etc are likely going to come from asteroids.
Quote from: Robotbeat on 08/19/2011 04:22 pmPlanetary surfaces like Mars, definitely. You have a huge amount of resources available (tons and tons of free metal just within walking distance of any spot), you have an atmosphere that takes care of radiation shielding for you plus easy ISRU anywhere on the planet, you have frozen water, you have regolith that is rounded by aeolian processes instead of resembling broken glass (and thus can serve as a good growing medium, etc), the atmospheric pressure can be increased to high enough to not require pressure suits by increasing the surface temperature slightly through sprinkling carbon black powder strategically over the surface (the higher pressure also allowing liquid water and maybe even plants to grow on the surface, possibly), etc.All at rest with respect to you, as opposed to moving in different directions at different delta-vs.Uh, no, since Mars has no magnetic field to deflect high energy particles and radiation from the sun, it won't matter how thick you make the atmosphere on Mars. Mars is constantly losing its atmosphere to solar wind as well. You can make the atmosphere as thick as you want on Mars, and it still won't protect unshielded organisms from radiation/high energy particles.
Quote from: Warren Platts on 08/20/2011 07:28 pmThere's no evidence whatsoever that gold and uranium etc. are likely going to be found in higher concentrations than the Earth's or Moon's or Mars' crusts.I thought is had been established through examining meteorites that some asteroids do have exceptionally high concentrations of these elements. Quote from: Jim on 08/20/2011 07:31 pmQuote from: DarkenedOne on 08/20/2011 06:44 pmHowever the thing is that mining and refining machines do not necessarily require gravity, whereas people do. Yes, they do. For transport (to stay in buckets or conveyers) or for settlingI don't think space industry would be practical without artificial gravity, but I don't see providing it as an obstacle.
Yes, they do. For transport (to stay in buckets or conveyers) or for settling
Quote from: Warren Platts on 08/20/2011 07:28 pmQuote from: DarkenedOne on 08/20/2011 06:44 pmHowever the same goes for asteroids. Asteroids have many heavy elements in far greater abundance than planet surfaces. Iridium for example is 1000 times more prevalent in asteroids than it is on Earth. Gold, Uranium, and etc are likely going to come from asteroids.There's no evidence whatsoever that gold and uranium etc. are likely going to be found in higher concentrations than the Earth's or Moon's or Mars' crusts.This conversation has just freed me of a misconception I've been carrying for years.I had thought copper, silver and gold were platinum group metals. Some quick Googling has freed me of that error.How about PGMs in meteorites? Does the premise of Bill White's novel have merit?I will add my 2¢ -- the moon's low escape velocity can permit meteorites to hit the lunar surface at a lower velocity, allowing some meteorites to remain intact rather than vaporizing. The lack of lunar weather or active geology allows meteorites to remain at the impact site. So if there are asteroids with very valuable ore deposits, it's likely some of these have found their way to the lunar surface over the eons.Arguments for asteroidal resources are also arguments to do prospecting at the basins of lunar craters.
Quote from: Jim on 08/20/2011 07:31 pmYes, they do. For transport (to stay in buckets or conveyers) or for settlingCouldn't you use centrifugal settling?
The kinetic energy of such a big rock must be huge, so it's going to hard to find such a large meteorite in tact. Thus, you'll be reduced to running all over the place trying to find and then transport much smaller chunks.
Quote from: mmeijeri on 08/21/2011 05:24 pmQuote from: Jim on 08/20/2011 07:31 pmYes, they do. For transport (to stay in buckets or conveyers) or for settlingCouldn't you use centrifugal settling?When mining a practically weightless asteroid? Centrifugal forces will only make it harder to find a purchase on the asteroid, and it would likely cause the asteroid to fly apart if you spin it too much.