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1 hour ago, tater said:
3 hours ago, sevenperforce said:

Elon Musk is loud and obnoxious about how birth rates are dropping and so forth. This is an issue to some degree, in the sense that the taxpayer pool is going to shrink relative to the number of older people who are no longer paying taxes but continue to cost the economy more money. However, at a planetary scale, the problem is overpopulation, not underpopulation. The metric against which to measure is not population density (sure, the US has low population density but it’s also mostly uninhabitable) but consumption, and at the median consumption levels of Americans, you would already need 100% of the resources of approximately ten Earths to support Earth’s current population.

There seems to be strong agreement that world population will peak (fairly soon), and then decline. The global fertility rate right now is slightly under 2.5, about half what it was 50 years ago (2.1 is replacement rate).

Trend-of-total-fertility-rate-by-world-r

A funny thing happens if you extend that line back to before the beginning of that graph.

US_TFR_History_1933_to_Present.png

A graph that starts at a peak will lead to different conclusions than one which starts at the average.

We have two concurrent problems: consumption and production.

Historically, human society and population was limited by two things: mortality and access to local resources. Infant mortality was fairly high and resource depletion was a local issue. In order to survive as long as possible, it made sense to lean toward the r-strategist approach to reproduction. The more offspring you had, the better chance you had of several of your children reaching adulthood and being able to support you in your old age. More children also meant greater access to territory which mitigated local limitations on resources.

[yes, I promise this is very much on topic; this whole issue underlies the very reason why SpaceX exists and how their aspirations are motivated]

With Smith's The Wealth of Nations and the rise of industrialization, the locality of resource access became all but nonexistent in developed nations. Access to distant resources meant that there were no longer any immediate limitations on population growth, as if a bacterial colony was suddenly being fed a steady drip of nutrients. There were a lot of optimistic philosophers who insisted that the rise in access to resources, industrialization, and automation would generate a post-scarcity society.

However, society's approach to reproductive strategy lagged far behind industrialization. And so the prior linear population growth became exponential:

pop-us-1790-2000.png

1 hour ago, tater said:

Consumption is complex, usually you see what an outlier the US is in terms of energy consumption, for example, but energy consumption also correlates with metrics that result in improved wellbeing/quality of life. I suppose it could be argued that the small single-digit billions spent on space might be better spent on fusion, but presumably some billionaire is in that area right now, right?

Western societies eventually realized that k-strategy was wildly preferable to r-strategy once locality of access to resources was no longer a challenge. However, our society remained structured as if r-strategy was still dominant. Things like social security and our overall economic engine are predicated on continual population growth -- a nationwide Ponzi scheme, as it were. And so that is where things are looking dire: a shortfall of production.

At current consumption rates, our resource utilization is nearing the total capacity of our planet. That's simply a fact. To give the entire human population a median American quality of life, you would need ten planets the size of this one. And yeah, Americans are wasteful; you could probably cut that down to four planets by reducing waste and down to three planets by increasing efficiency. And maybe even down to two planets by reducing consumption without decreasing the actual quality of life. But we are still above the level that our planet can support.

The only reason decreased population growth is seen as "bad" is because our societies were structured as giant Ponzi schemes. That's the thing we actually have to change.

1 hour ago, tater said:

Bottom line is that all this billionaire spending is chump change. Any complaints IMHO are really "opportunity cost" complaints that these billionaires are more effective with less money than government. The tiny billions spent would be better spent doing X instead of Y. The trouble of course is that governments are already spending to "do X" and at default levels that are easily in excess of what the billionaires would ever spend, just like NASA probably spends >10X what SpaceX or BO spends per year by itself. USAID alone spends ~$8.5B/yr in sub-Saharan Africa. One US gov entity spending probably 4X SpaceX spending on part of Africa.

Yep, agreed.

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3 hours ago, tater said:

Bottom line is that all this billionaire spending is chump change. Any complaints IMHO are really "opportunity cost" complaints that these billionaires are more effective with less money than government. The tiny billions spent would be better spent doing X instead of Y. The trouble of course is that governments are already spending to "do X" and at default levels that are easily in excess of what the billionaires would ever spend, just like NASA probably spends >10X what SpaceX or BO spends per year by itself. USAID alone spends ~$8.5B/yr in sub-Saharan Africa. One US gov entity spending probably 4X SpaceX spending on part of Africa. Is the argument that the gov spending is not useful, and that the focus of Bezos or Musk would get grossly better results for less $$$? I'm open to that being true, but that seems to point at fixing the gov programs as the way to move forward (on topic, it's like SLS vs Starship).

I know of a great many charities, NGOs, research institutes and other worthy causes who would be very glad of a piece of that chump change.  I'm betting you do too, although we may well differ in our definitions of a worthy cause.  And clearly, for those cases,  governments aren't spending to do X, or at least they're not spending so much that they're squeezing out all the charities etc. in the process.

But anyway - you're probably right re. the billionaire spending.  A Mars colony though is going to require vastly more money than even Bezos or Musk can dig out from behind the couch cushions. And that level of money could, and should be better spent on Earth IMO.

It probably won't be though.

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30 minutes ago, sevenperforce said:

At current consumption rates, our resource utilization is nearing the total capacity of our planet. That's simply a fact. To give the entire human population a median American quality of life, you would need ten planets the size of this one. And yeah, Americans are wasteful; you could probably cut that down to four planets by reducing waste and down to three planets by increasing efficiency. And maybe even down to two planets by reducing consumption without decreasing the actual quality of life. But we are still above the level that our planet can support.

That could be a Bezos argument for capturing extraterrestrial resources ;)

Maybe he's thinking about Amazon expansion? Hehe.

Regarding the US pop by region, that is not at all the same as fertility, it includes immigration. The US fertility rate is <2.1, as your other chart shows, and has been since the 60s (might have bumped into replacement a few years there). The US fertility rate clearly shows the baby boom—and yeah, the Ponzi scheme nature of social safety nets in every society that has them is clear, and certainly in danger of failure.

I'm not sure where SpaceX motivation is in the context of any of this, though I think their current efforts actually enable the Bezos view. As has come up here numerous times, I'm in far closer alignment with Blue Origin goals than SpaceX goals, which is perhaps why I'm often harsh on BO. It's a similar opportunity cost issue, he's spending the money anyway, so why not just do it already! In the meantime, Starship, even if meant for Mars I think will open access to things like asteroid mining, etc—unlike Bezos I tend to think it's done by robots, not people, so I am unsure about ever seeing "millions of people living and working in space" unless the time horizon is MUCH farther out there.

 

Just now, KSK said:

But anyway - you're probably right re. the billionaire spending.  A Mars colony though is going to require vastly more money than even Bezos or Musk can dig out from behind the couch cushions. And that level of money could, and should be better spent on Earth IMO.

It probably won't be though.

I'm not a colonize Mars person, myself. But the only money to complain about here is whatever Musk/Bezos personally spend on SpaceX/BO. It's a small number of billions per year, combined. Not sure what they are supposed to do that's better, since "better" would invariably be an opinion.

The best Musk argument for his Mars goals (IMHO) is the one that says "it's cool" or "it's the science fiction world I want to live in."

Should I complain about people—often not of high means—who spend large amounts on fancy sneakers? That's a >$20B annual industry in the US alone. Surely the cheaper sneakers I wear until they fall apart before replacing would be a better use of resources (and I can afford arbitrarily expensive sneakers). So Musk should kill Starship, and spend $2B/year on whatever program in Africa, instead, but it's apparently too much to ask American sneaker aficionados to spend 10% less per year on Jordans?

(presumably they all donate that sneaker money to a charity that helps people with lower standards of living abroad)

EDIT: my knowledge of what particular sneaker is popular could literally be wrong by decades, that's the only particular type I know of as expensive/popular :D

 

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37 minutes ago, tater said:

I'm not a colonize Mars person, myself. But the only money to complain about here is whatever Musk/Bezos personally spend on SpaceX/BO. It's a small number of billions per year, combined. Not sure what they are supposed to do that's better, since "better" would invariably be an opinion.

The best Musk argument for his Mars goals (IMHO) is the one that says "it's cool" or "it's the science fiction world I want to live in."

Should I complain about people—often not of high means—who spend large amounts on fancy sneakers? That's a >$20B annual industry in the US alone. Surely the cheaper sneakers I wear until they fall apart before replacing would be a better use of resources (and I can afford arbitrarily expensive sneakers). So Musk should kill Starship, and spend $2B/year on whatever program in Africa, instead, but it's apparently too much to ask American sneaker aficionados to spend 10% less per year on Jordans?

(presumably they all donate that sneaker money to a charity that helps people with lower standards of living abroad)

EDIT: my knowledge of what particular sneaker is popular could literally be wrong by decades, that's the only particular type I know of as expensive/popular :D

 

Fair. Telling other folks what to spend their money on (or not) is a fools errand, even if I have... views, on what they're spending it on. In this particular example, I have definite views on overpriced designer gear, the fashion industry in general, disposable fashion in particular, and everything else that goes with that. But this is neither the place or the time for that digression.

As for "it's the science fiction world I want to live in",  I've read enough science fiction to find  that a less than comforting reason for an arch-capitalist to do anything.  Having a new life available in the off-world colonies didn't stop it royally sucking back on Earth.  But hey - if the Mars colony runs into real trouble, there's always Soylent Green to fall back on.

 

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Just a friendly reminder here to try to keep it on topic, please.  There's a quite lengthy conversation going that has become only tangentially related to the topic of the thread. 

If you would like to keep discussing details of overpopulation and the effects it has on off world colonization, or the economics of spending money on space versus other areas, please feel free to fire up separate threads.  Just remember to keep it civil and to keep the politics out of it.

 

Thank you.

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Although vaguely on topic, more content relating to fertility rates has been posted after a moderator asked people to take it to a new thread. The new content has therefore been removed. It's easy to miss a moderator's post when you're catching up on a thread, so I'll just highlight it so people skimming though will notice:

11 hours ago, Geonovast said:

If you would like to keep discussing details of overpopulation and the effects it has on off world colonization, or the economics of spending money on space versus other areas, please feel free to fire up separate threads. 

Anything else posted on these topics in this thread will just get removed, so please don't waste all that time and research for nothing :)

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1 hour ago, Admiral Fluffy said:

What would be the viability of using starship to recover the Hubble? 

The solar panels on Hubble are not designed to retract, and at the very least would need to be removed.

Also, Hubble was never designed for return, so it may not be able to survive even a 'gentle' reentry.

Removing the solar panels and recovering Hubble would most likely require combined Starship and EVA activities, so it may be a while before there is an opportunity to even make the attempt.

Edited by Terwin
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1 hour ago, Terwin said:

Removing the solar panels and recovering Hubble would most likely require combined Starship and EVA activities, so it may be a while before there is an opportunity to even make the attempt.

I have a sudden vision of a Canada-arm equipped starship dragging Hubble to ISS and using puppy-dog eyes to try to get the ISS astronauts to package up Hubble for return in it's cargo bay...

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5 hours ago, Admiral Fluffy said:

People here would know this.

What would be the viability of using starship to recover the Hubble? 

It'd be a matter of building the custom grappling hardware necessary to hold it, running simulations to verify it would survive (a return to Earth was planned for, but not on Starship), and after all that you'd need to find the crew of astronauts to pack it, or find a way to do it all with robots.

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7 hours ago, Admiral Fluffy said:

People here would know this.

What would be the viability of using starship to recover the Hubble? 

I think a key point here is whether Starship could hold crew and cargo at the same time, like the Shuttle could. You'd need EVA-capability on the crewed part, cargo doors big enough to fit Hubble (sans solar panels), a Canadarm to grapple the telescope into the cargo bay, and astronauts to do the final strapping-down. 

If the Starship comes in either crew or cargo configuration, but not both at the same time, things get a lot more complicated. Having to rendezvous three craft so close to each other that astronauts could travel between them, KSP-style, would presumably be a bit of a safety nightmare.

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4 hours ago, Codraroll said:

If the Starship comes in either crew or cargo configuration, but not both at the same time, things get a lot more complicated. Having to rendezvous three craft so close to each other that astronauts could travel between them, KSP-style, would presumably be a bit of a safety nightma

Would be good practice for Gateway/HLS operations, or vice-versa. Rapid launch rate is a key tenet of Starship, after all. Cargo ship launches, grapples Hubble with its standard Canadarm 33-1/3. Crew ship launches, docks to cargo, starts flinging packing peanuts about. It really would be a great test/testament to exactly the kind of semi-improvised spacework that’s going to be necessary to really industrialize space. 
 

Or, there’s always Optimus… <_<

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