Quote from: high road on 11/20/2014 03:49 pmQuote from: RanulfC on 11/19/2014 08:29 pmQuote from: Elmar Moelzer on 11/19/2014 03:52 pmIf it is economically feasible to send resources from Mars to Earth. How much more economically feasible would it be to mine the ocean floor and send resources from the bottom of the ocean to the surface? Why are there no colonies under water that do that?The obvious answer of course is that you don't NEED a "colony" to extract and ship resources, it just takes some robots and remote equipment. Of course having your "support" on the surface of the ocean for all this stuff is WAY cheaper than having that same support network on Mars in ANY situation.I very much suspect that it COULD actually become economical to ship resources from Mars to Earth. But the underlying circumstances are that you ALREADY have to have the transportation system established and on-site support in place. In other words it MAY at some point become economic for a Mars colony to ship 'something' back to Earth at a "profit" as long as you assume all the "sunk" costs of getting there and setting up are never included in your "pricing" plan.Randynot to mention the technology developed and the exploration done. But hey, even the virginia company went broke, and the people on the mayflower would never have been able to pay for all the exploration missions of the new world. But guess where todays most powerful nation is. And all that without the spices columbus set out to get.certainly. The public funds of Portugal and Spain were responsible for exploring most of the New World. The british colonies originally only settled a very tiny part of it.most of it had already been explored by the original settlers after they entered the land from the Beiring Strait.
Quote from: RanulfC on 11/19/2014 08:29 pmQuote from: Elmar Moelzer on 11/19/2014 03:52 pmIf it is economically feasible to send resources from Mars to Earth. How much more economically feasible would it be to mine the ocean floor and send resources from the bottom of the ocean to the surface? Why are there no colonies under water that do that?The obvious answer of course is that you don't NEED a "colony" to extract and ship resources, it just takes some robots and remote equipment. Of course having your "support" on the surface of the ocean for all this stuff is WAY cheaper than having that same support network on Mars in ANY situation.I very much suspect that it COULD actually become economical to ship resources from Mars to Earth. But the underlying circumstances are that you ALREADY have to have the transportation system established and on-site support in place. In other words it MAY at some point become economic for a Mars colony to ship 'something' back to Earth at a "profit" as long as you assume all the "sunk" costs of getting there and setting up are never included in your "pricing" plan.Randynot to mention the technology developed and the exploration done. But hey, even the virginia company went broke, and the people on the mayflower would never have been able to pay for all the exploration missions of the new world. But guess where todays most powerful nation is. And all that without the spices columbus set out to get.
Quote from: Elmar Moelzer on 11/19/2014 03:52 pmIf it is economically feasible to send resources from Mars to Earth. How much more economically feasible would it be to mine the ocean floor and send resources from the bottom of the ocean to the surface? Why are there no colonies under water that do that?The obvious answer of course is that you don't NEED a "colony" to extract and ship resources, it just takes some robots and remote equipment. Of course having your "support" on the surface of the ocean for all this stuff is WAY cheaper than having that same support network on Mars in ANY situation.I very much suspect that it COULD actually become economical to ship resources from Mars to Earth. But the underlying circumstances are that you ALREADY have to have the transportation system established and on-site support in place. In other words it MAY at some point become economic for a Mars colony to ship 'something' back to Earth at a "profit" as long as you assume all the "sunk" costs of getting there and setting up are never included in your "pricing" plan.Randy
If it is economically feasible to send resources from Mars to Earth. How much more economically feasible would it be to mine the ocean floor and send resources from the bottom of the ocean to the surface? Why are there no colonies under water that do that?
One problem: the scale height on Mars is quite a bit greater than on Earth, so atmospheric pressure, though it is much less at the surface, also falls off more slowly with height, making the climb-out more difficult than you might assume. At some altitude, Martian atmospheric pressure becomes greater than that on Earth at the same altitude. (Unless I miss my guess, though, the same effect makes ballistic re-entry easier on Mars, all other factors being the same.)
Quote from: Donosauro on 11/19/2014 05:33 pmOne problem: the scale height on Mars is quite a bit greater than on Earth, so atmospheric pressure, though it is much less at the surface, also falls off more slowly with height, making the climb-out more difficult than you might assume. At some altitude, Martian atmospheric pressure becomes greater than that on Earth at the same altitude. (Unless I miss my guess, though, the same effect makes ballistic re-entry easier on Mars, all other factors being the same.)you are right, the top of Olympus Mons has a pressure of 70 pascals, which I gather is about 51km height on Earth?
The obvious answer of course is that you don't NEED a "colony" to extract and ship resources, it just takes some robots and remote equipment. Of course having your "support" on the surface of the ocean for all this stuff is WAY cheaper than having that same support network on Mars in ANY situation.