So the big advantage of planets is that you can pollute them all you want without (in the foreseeable future) running out of the raw materials you're not bothering to recycle? That's the second most common argument against space exploration I hear all the time.
Bear in mind that not a single city on earth is self-sufficient, and that even our entire society isn't self-sufficient as we keep burning through mineral reserves and billions of years worth of fossil fuels.
Quote from: daveklingler on 11/02/2016 05:12 amHuh? C is a relatively straightforward engineering development process that begins with a spacecraft tethered to a spent stage.Such a configuration would be for testing purposes only, not for normal use.
Huh? C is a relatively straightforward engineering development process that begins with a spacecraft tethered to a spent stage.
I think it will take many decades, maybe even centuries. My career has been in the manufacturing world, so I know how hard it is to make things even in the middle of civilization.But making the same size colony out in space, and not on a big lump of atoms, will take far longer.
QuoteOkay, first of all, they're all space colonies. That's my point. This idea that Mars is somehow an easier place to start a space colony, because it's a planet and therefore easier because it's a planet and therefore easier, is an unfounded assumption.The same can be said about colonies not on a planetoid. However I would characterize it as a calculated assumption. And it's certainly one that many feel is worth pursuing.
Okay, first of all, they're all space colonies. That's my point. This idea that Mars is somehow an easier place to start a space colony, because it's a planet and therefore easier because it's a planet and therefore easier, is an unfounded assumption.
QuoteRegarding resources, some time soon (< 10 years) after we (humans) begin launching asteroid retrieval spacecraft, small asteroids measuring in the half-kiloton range can begin to arrive in cislunar space, ready for retrieval to wherever we place stations. A station in LEO can make a relatively rapid progression, using conventional equipment shipped from nearby, to the point where it can refine and smelt small amounts of ore.All of our mineral extraction techniques here on Earth rely upon 1G gravity, free access to as much air as is needed, and in some cases bulk quantities of complex chemicals.All we'll have in space is lots of heat and cold, so I'm not sure extracting minerals in space is going to happen at a very rapid pace.
Regarding resources, some time soon (< 10 years) after we (humans) begin launching asteroid retrieval spacecraft, small asteroids measuring in the half-kiloton range can begin to arrive in cislunar space, ready for retrieval to wherever we place stations. A station in LEO can make a relatively rapid progression, using conventional equipment shipped from nearby, to the point where it can refine and smelt small amounts of ore.
QuoteBased on what we've learned from ISS about equatorial LEO radiation levels, guilt-free baby-making can start immediately. Al Globus says so.Somehow I don't think there will be a rush to make babies in space right away. But as I said earlier, I think in-space colonies and Mars colonies can exist at the same time, and even complement each other.
Based on what we've learned from ISS about equatorial LEO radiation levels, guilt-free baby-making can start immediately. Al Globus says so.
Let's cut to the chase here - I don't know anyone that thinks Mars will be self-sufficient anytime soon. If we're lucky maybe a century, but I wouldn't be surprised if it's far longer.So self-sufficiency is not required to start colonization off of Earth, either for Mars or in-space colonies, since it's a long-term goal, not a near-term one.
It's highly unlikely that any government on Earth is going to support a Mars colony in the foreseeable future, and any Mars colony would require constant support for the foreseeable future. For an orbital colony, the necessary support is orders of magnitude smaller and yet still highly difficult to justify.
Tourism will be the first target, and although the market surveys look okay we'll have to wait and see whether that works.
I've wondered myself whether, if we get better at bringing NEOs to LEO and sending products to the surface inexpensively, farming could turn out to be profitable, say on high-value crops that can be grown 24/7 without regard to seasons, insects, blights or natural disasters.
But near self-sufficiency is relatively necessary right off the bat for a Mars colony, given the difficulty of supporting one...
...and self-sufficiency is inherently necessary to meet the goal of establishing a "Plan B for humanity", which is the reason most often cited by putative Mars colonists when asked why in tarnation we'd ever want to try to colonize Mars.
Quote from: daveklingler on 11/03/2016 02:14 amBut near self-sufficiency is relatively necessary right off the bat for a Mars colony, given the difficulty of supporting one...That is not what Elon Musk is planning. His plan is to double the number of ships going to Mars every synodic cycle. No one knows if that will happen, but it's clear Musk plans to keep transporting people and materials to Mars in ever increasing amounts. So the plan is not "one and done".
Quote...and self-sufficiency is inherently necessary to meet the goal of establishing a "Plan B for humanity", which is the reason most often cited by putative Mars colonists when asked why in tarnation we'd ever want to try to colonize Mars.Sure. But there is no defined need date to make that happen, since we don't know when/if the end of the Earth is coming.It is curious though that you're implying that LEO colonies will never become self-sufficient, yet you pan Mars colonists for trying. Seems like a double standard to me...
Quote from: daveklingler on 11/03/2016 01:55 amIt's highly unlikely that any government on Earth is going to support a Mars colony in the foreseeable future, and any Mars colony would require constant support for the foreseeable future. For an orbital colony, the necessary support is orders of magnitude smaller and yet still highly difficult to justify.Absent some currently unknown "National Imperative", I know of no reason the U.S. Government would spend any public money to directly finance or support a colony off of Earth - regardless where it is. And I think the same applies to other governments too.That's not to say that various governments wouldn't spend money to pursue "science", and pay Bezos or Musk to do what they already plan to do so that the governments can tag along. But I don't foresee that being a majority of the overall funding.I think colonizing space is going to have to be a primarily privately funded effort. I'm certainly willing to throw some play money at it, and probably others would be too. But I don't see any significant revenue streams coming in to help finance any of these efforts.
QuoteTourism will be the first target, and although the market surveys look okay we'll have to wait and see whether that works.Sorry, but no. The market for "experiential travel" (which is what space tourism is initially) is not that big. And overall tourism is a byproduct of humanities expansion, not a leader. Plus, what is a space tourist supposed to do?
Ironically crops grown in LEO could be sold to Mars colonists...
As I've said, Mars colonies have an explicit requirement to become as self-sufficient as possible in the shortest timespan possible because of the high difficulty in supporting them. That is a completely different standard.
Just to be clear, I think there is a lot of things that are common between what Jeff Bezos wants to do in space and what Elon Musk wants to do on Mars.
And luckily both have the ability and resources to work on lowering the cost to access space, which is certainly a major barrier to expanding humanity out into space - anywhere in space.Personally I have more near-term interest in creating LEO space stations, but that is because I've taken an interest in 1st generation rotating space station designs that are scaleable. It's just a hobby, but I think I understand the challenges involved.
I'm also fascinated by Musk's plans for Mars, although I don't yet understand how his colonization plan is supposed to work, but based on his past success I'm willing to give him some time to figure it out.
In comparison, all we have from Jeff Bezos is the transportation part of the goal he supports, so there is less to get excited over - but hopefully that will change with time too...
Quote from: daveklingler on 11/03/2016 02:42 amAs I've said, Mars colonies have an explicit requirement to become as self-sufficient as possible in the shortest timespan possible because of the high difficulty in supporting them. That is a completely different standard.That's your standard, not Musk's. And he gets to set the goals for his Mars colony, not anyone else.
Quote from: high road on 11/02/2016 07:00 amSo the big advantage of planets is that you can pollute them all you want without (in the foreseeable future) running out of the raw materials you're not bothering to recycle? That's the second most common argument against space exploration I hear all the time.I wasn't aware that we'd run out of any raw materials here on Earth. Definitely not of the mineral kind.
And if given the chance to start anew on a new world, we certainly have a lot of lessons learned that we'll be able to apply. For instance, recycling aluminum can significantly reduce the need to mine and refine more aluminum, so I think Mars colonists will be very good recyclers.
QuoteBear in mind that not a single city on earth is self-sufficient, and that even our entire society isn't self-sufficient as we keep burning through mineral reserves and billions of years worth of fossil fuels.Let's cut to the chase here - I don't know anyone that thinks Mars will be self-sufficient anytime soon. If we're lucky maybe a century, but I wouldn't be surprised if it's far longer.So self-sufficiency is not required to start colonization off of Earth, either for Mars or in-space colonies, since it's a long-term goal, not a near-term one.
In economics, 'self sustaining' means raking in more revenue than what's needed to cover the cost. But this means exporting enough goods and services to pay for what needs to be imported.
Quote from: high road on 11/03/2016 07:03 am In economics, 'self sustaining' means raking in more revenue than what's needed to cover the cost. But this means exporting enough goods and services to pay for what needs to be imported.But a Mars settlement will not use this definition. It will need to be self sustaining in the sense that they can survive when the supply line is cut. I agree that it will take a century but they would very conciously work towards that goal. It is the very reason for its existence. It would drive the financers and the settlers.Edit: I wrote "for Mars". It seems the rationale for space industry and millions of people living in space as in Jeff Bezos' vision would have a different outlook.
Exactly. Aluminum is not the best example because we're already doing our best to recycle as much as we can (well, in Europe at least, can't speak for the entire world), but phosphorus, fuel, water, plastics, etc. All things we carelessly throw away on earth because we have easily accessible reserves...
Same goes for a colony in space, which has to 'import' stuff from asteroids or the moon. They will use the same techniques, as far as spin gravity allows for using the same techniques, as planetary colonies will.
i'll try and explain this more clearly: a colony on Mars that is capable of providing its citizens with food, water, air, and habitation, what people on this forum mean with self-sufficiency, but has no valuable export, will see a steady decline in population as people try to get back to the higher living standards of Earth. The only way to keep them there, is to screw up earth so it's a worse place ot live than Mars.
That's the point: a colony that is set up with the only goal that it will eventually be able to sustain it's citizens, will not last unless it does more than just sustaining them. In economics, 'self sustaining' means raking in more revenue than what's needed to cover the cost. But this means exporting enough goods and services to pay for what needs to be imported.i'll try and explain this more clearly: a colony on Mars that is capable of providing its citizens with food, water, air, and habitation, what people on this forum mean with self-sufficiency, but has no valuable export, will see a steady decline in population as people try to get back to the higher living standards of Earth. The only way to keep them there, is to screw up earth so it's a worse place ot live than Mars.
Mars as a backup for humanity is a feature of a fully sufficient Mars colony, but from a practical standpoint it is not a good reason to colony Mars. It will cost too much. Reaching a one million person colony that needs no input from Earth will be incredibly expensive. Good luck on getting funding if that's the primary reason.For a fraction of the cost of a fully sufficient Mars colony, most of the civilization collapsing scenarios on Earth can be mitigated. Asteroid defense, civil defense, disaster relief, securing food production, reducing poverty, renewable energy, etc.
And Elon Musk has even stated that there is no economic engine of growth. I believe his example was that even if they found pure cocaine on the surface of Mars, it would be uneconomical to ship it back to Earth.
Quote from: RonM on 10/31/2016 04:47 amMars as a backup for humanity is a feature of a fully sufficient Mars colony, but from a practical standpoint it is not a good reason to colony Mars. It will cost too much. Reaching a one million person colony that needs no input from Earth will be incredibly expensive. Good luck on getting funding if that's the primary reason.For a fraction of the cost of a fully sufficient Mars colony, most of the civilization collapsing scenarios on Earth can be mitigated. Asteroid defense, civil defense, disaster relief, securing food production, reducing poverty, renewable energy, etc.It is a mistake to think Mars colony would be more expensive than fixing Earth, in fact it's the opposite. For example, Imperial College London estimates the cost to half CO2 emissions by 2050 is $2 trillion per year, that's just one of the problems in your long list. The cost of a Mars colony would be rounding error comparing to the resources we spent and will be spending to maintain Earth.It is a common misconception to think Earth is better than Mars because we have "free" air, water and good temperature range, but none of these are truly free. They're the product of a super complex, global scale ecosystem and climate, which is being strained by 7 billion people. Maintaining and fixing this complex system is going to make the ECLSS for a Mars colony like child's play, and that's ignoring man-made problems like politics, religion and war.