I mean, if you, a guy (presumably) sitting (presumably) quietly (presumably) in the comfort of your own home (presumably) can't understand what he's saying after I carefully laid it out in text for you, what hope do a bunch of people sitting in a crowded audience have?
Carrying over this quote from the parent thread:Quote from: QuantumG on 10/26/2014 01:30 am I mean, if you, a guy (presumably) sitting (presumably) quietly (presumably) in the comfort of your own home (presumably) can't understand what he's saying after I carefully laid it out in text for you, what hope do a bunch of people sitting in a crowded audience have?This is an unnecessarily snarky reply and I am surprised at your uncharacteristic naïvety. There is no reason to lose revenue in making the return trip free of charge despite (assumption on your part) excess capacity.
They can come back if they like, if they don't like it, of course. You get a free return ticket. There's sometimes a debate about going to Mars one-way and whether that makes things easier, and I think for the initial flights perhaps, but long term, to get the cost down, you need the spacecraft back. Whether the people come back is irrelevant, but you must have the ship back because those things are expensive. So anyone who wants to return can just jump on. - source
While you and I may see how silly it is to talk about the return trip being "free", Elon doesn't. We can't just ignore what he's said because we think it's silly, if we did we'd ignore so much more than this.
Since the subject got several pages of discussion on this thread, I thought I'd create a new thread to continue the discussion without going off topic on the original thread. The gist of it as QuantumG observed is, in a scenario where you have MCT's providing half a million dollar tickets to Mars for colonists, there may very well be a business case for exporting stuff.
Would it be wise for a colony to expend extra propellant(water derived which is a finite resource that escapes like Helium does on Earth) shipping trinkets to Earth? Further more, if the colony is dependant on recieving goods from Earth in return, what happens when it grows to a large size and the gold rush stops? I can see the Mars authorities taking California water police to the next couple levels. I think intellectual property might be the only required trade between the two planets. Earth technology would be highly valuable on Mars and Mars could invent things of its own to pay for its small scale license manufacturing on Mars. Of course, Mars goods would cost more because of less mass production and environmental reasons and so the standard of living might be lower.Of course, this may be the rational approach and Mars politicians will just see the short term dollar signs and do it anyway.
Quote from: ncb1397 on 10/26/2014 12:05 pmWould it be wise for a colony to expend extra propellant(water derived which is a finite resource that escapes like Helium does on Earth) shipping trinkets to Earth? Further more, if the colony is dependant on recieving goods from Earth in return, what happens when it grows to a large size and the gold rush stops? I can see the Mars authorities taking California water police to the next couple levels. I think intellectual property might be the only required trade between the two planets. Earth technology would be highly valuable on Mars and Mars could invent things of its own to pay for its small scale license manufacturing on Mars. Of course, Mars goods would cost more because of less mass production and environmental reasons and so the standard of living might be lower.Of course, this may be the rational approach and Mars politicians will just see the short term dollar signs and do it aThere is no shortages of resources anywhere. But Mars politicians could certainly make Mars a wasteland.For one thing there could be more fresh water on Mars than there is fresh water on Earth. 10 times more.But Mars has not been adequately explored to determine this.On earth most fresh water is in glaciers- if you exclude that fresh water [which no one is using, has used, or may not within a century] that it becomes even more likely there is more fresh water on mars. But then again, other than Mars polar caps, we don't actually know how much of Mars water is fresh.Now if have settlements on Mars [more than 100] then it's likely that things like asteroids are mined, and one can get more water mining asteroids than in the salty seas of Earth.There is no storage of water in space- where do imagine the water on Earth came from?
Would it be wise for a colony to expend extra propellant(water derived which is a finite resource that escapes like Helium does on Earth) shipping trinkets to Earth? Further more, if the colony is dependant on recieving goods from Earth in return, what happens when it grows to a large size and the gold rush stops? I can see the Mars authorities taking California water police to the next couple levels. I think intellectual property might be the only required trade between the two planets. Earth technology would be highly valuable on Mars and Mars could invent things of its own to pay for its small scale license manufacturing on Mars. Of course, Mars goods would cost more because of less mass production and environmental reasons and so the standard of living might be lower.Of course, this may be the rational approach and Mars politicians will just see the short term dollar signs and do it a
The gravity well is one of the reasons why I think Dwarf planets or moons make better candidates for colonization than planets. You have more resources than an asteroid or comet but you can get off the surface much easier.
Quote from: ncb1397 on 10/26/2014 01:56 pmThe gravity well is one of the reasons why I think Dwarf planets or moons make better candidates for colonization than planets. You have more resources than an asteroid or comet but you can get off the surface much easier.Well, exporting stuff from the Moon is certainly much easier. The trip time is a lot shorter and the gravity well is much more shallow. If you have a mass driver, the energy needed to send something to escape velocity from the moon is only ~2.9 MJ/kg or 0.8 kWh/kg.You can compare this with say the amount of energy needed to make aluminium from Bauxite, which is ~50 MJ/kg. The marginal cost of exporting even bulk materials from the moon becomes VERY low once your lunar base grows past a certain threshold.