bestonnet, there you go again. Do you really think that the only place for a solar panel is in a forest?

There are some places where that is the only place to put solar panels.

lpetrich:

You remind me of the Kennedy family, which despite its claims of greenie credentials, opposes the Cape Wind offshore wind farm at Cape Cod.

I don't see how I could considering that I'd be quite happy to have one of my preferred power sources right in my backyard (although it just so happens that my preferred power sources don't have the infrasonic problem or strobe light effect of wind power).

lpetrich:

That spacecraft carries 3 people, which is where I got the 7500 gallons/person or 140 barrels/person. So to send a billion people into low earth orbit, you'd need half of Saudi Arabia's estimated reserves of crude oil.

Which is quite doable (and if you've just assumed that all of that >250 t propellent is fuel then you've overestimated the amount of oil needed since most of the propellent is actually LOX).

Of course in the long term we'll end up switching to synthetic fuels at which point we'll be able to make the fuel from CO2 from the atmosphere and water.

lpetrich:

Notice that I said "low earth orbit" -- to get out of there requires additional rocket propellant. And to live in outer space for any length of time, one will have to have much more volume per person and much more food biomass per person than will be available in a Soyuz spacecraft.

It is often said that Low Earth Orbit is half way to anywhere (and by the time we're moving even millions of people into space we'll have a pretty well developed space infrastructure with many space stations to dock to and with food grown in space).

lpetrich:

It's possible to construct solar-electric or nuclear-electric low-thrust rockets; it has actually been done in the form of the SMART-1 rocket to the Moon. But such rockets are awfully slow.

There have been a lot of other solar-electric spacecraft and they've worked pretty well (though somewhat slowly), I'm not aware of any use of nuclear-electric propulsion so far although the technology to do it is all out there.

Of course there is also the nuclear thermal rocket which provides a higher exhaust velocity than a chemical rocket and enough thrust for manned applications. The US got it to the point at which it was almost ready for a test flight before it was cancelled (since the US government had decided not to go to Mars).

lpetrich:

And mining asteroids? Don't make me laugh. Point me to a reasonably cost-effective way of extracting metals from metal silicates, as compared to extracting them from metal oxides or carbonates or sulfates or chlorides or other common ore chemistries. I remember trying to research this question and coming up empty-handed. There might be something in some mining journal somewhere, but such publications are usually buried in university libraries or behind paywalls.

Some asteroids are just giant lumps of Iron-Nickel alloy and many others contain quite a significant amount of oxides (including chondrites which are the most common type).

Although even silicates can be mined, you just need to provide enough energy (which is much easier to do in space where solar concentrators can be very flimsy).

lpetrich:

And the mining machines would have to be built, and then sent to those asteroids.

The idea is that the equipment used to mine the asteroids would be a lot lighter than the materials you'd get out of mining it.

And let's take a look at the Soyuz spacecraft again. The spacecraft's mass is about 7120 kg, and it takes the equivalent of 22500 gallons of gasoline to get it into orbit. That's about 3000 gallons/ton or 60 barrels/ton, and that's into low earth orbit.

That spacecraft carries 3 people, which is where I got the 7500 gallons/person or 140 barrels/person. So to send a billion people into low earth orbit, you'd need half of Saudi Arabia's estimated reserves of crude oil.

Notice that I said "low earth orbit" -- to get out of there requires additional rocket propellant. And to live in outer space for any length of time, one will have to have much more volume per person and much more food biomass per person than will be available in a Soyuz spacecraft.

It's possible to construct solar-electric or nuclear-electric low-thrust rockets; it has actually been done in the form of the SMART-1 rocket to the Moon. But such rockets are awfully slow.

And mining asteroids? Don't make me laugh. Point me to a reasonably cost-effective way of extracting metals from metal silicates, as compared to extracting them from metal oxides or carbonates or sulfates or chlorides or other common ore chemistries. I remember trying to research this question and coming up empty-handed. There might be something in some mining journal somewhere, but such publications are usually buried in university libraries or behind paywalls.

And the mining machines would have to be built, and then sent to those asteroids.

Why is it necessary to use fossil fuels?

If we need the energy, aren't allowed to use fission, don't have the technology to do fusion or the infrastructure to do space power systems and don't have the geology to use one of the useful renewables (i.e. hydro and geothermal) then there's really no alternative to fossil fuels. This happens to describe quite a lot of places including where I am.

lpetrich:

Is it dishonorable to use renewables?

There are niche markets in which renewables are useful (e.g. off grid power only needed during the day) but the ones that can be used everywhere can't handle baseload without storage technology we currently don't have.

lpetrich:

And moaning and groaning about how putting up solar panels will lead to deforestation -- that seems like unconvincing pseudo-environmentalism.

Actually it is those who are proposing putting up the solar panels that are engaging in pseudo-environmentalism.

Deforestation is actually a big environmental issue and not something we should be trying to make worse just to feel good about not burying a small amount of waste where it won't enter the environment.

lpetrich:

I don't think that bestonnet realizes how difficult it is to travel in outer space. There are a lot of things that you have to provide for your human crews that on Earth we either get for free or else that are much less costly to acquire. Air. Water. Food. An appropriate temperature. A suitable volume to move around in.

Those are all things we can do and have been able to do for decades.

lpetrich:

I once calculated that the amount of rocket fuel that an astronaut needs for going into low earth orbit is the equivalent of 7500 gallons of gasoline, and that is working from the Soyuz rocket, not the Space Shuttle.

The actual figures for how much a Soyuz uses (more than 250 t of propellent) are easily available but largely irrelevant at present since propellent costs are actually a very tiny proportion of the cost of a space launch (even for rockets using expensive Hypergolic propellants instead of relatively cheap LOX, hydrocarbons or hydrogen (and the hydrogen comes from fossil fuels anyway)).

lpetrich:

And as to mining the Moon, that would be OK for silicon and the more common metals, but for hydrogen and nitrogen and other volatiles, forget it.

For a space power satellite most of the mass would be metal structure and silicon which can be obtained from the moon just fine.

For a space colony most of the mass would be radiation shielding and you don't really care what materials you use, just as long as you have enough mass so slag left over from ore processing will do just fine with the second largest mass being the structure. Hydrogen containing substances are better at stopping the radiation in space but that's only really going to matter for spaceships, not space colonies that are meant to stay in one place.

Bringing what little Hydrogen, Carbon and Nitrogen we need from Earth would work just fine provided we can get most of the mass we need from space (and we'll need to prove the technology used for space mining, so it's probably not a good idea to rely on it if you can avoid it).

lpetrich:

It's possible to go to the outer Solar System or some comet to get ice, but the only thing one will save is rocket propellant -- that will be an extremely time-consuming solution.

A lot of near earth asteroids are probably burnt out comets that still have a lot of volatiles.

And moaning and groaning about how putting up solar panels will lead to deforestation -- that seems like unconvincing pseudo-environmentalism.

I don't think that bestonnet realizes how difficult it is to travel in outer space. There are a lot of things that you have to provide for your human crews that on Earth we either get for free or else that are much less costly to acquire. Air. Water. Food. An appropriate temperature. A suitable volume to move around in.

I once calculated that the amount of rocket fuel that an astronaut needs for going into low earth orbit is the equivalent of 7500 gallons of gasoline, and that is working from the Soyuz rocket, not the Space Shuttle.

And as to mining the Moon, that would be OK for silicon and the more common metals, but for hydrogen and nitrogen and other volatiles, forget it. It's possible to go to the outer Solar System or some comet to get ice, but the only thing one will save is rocket propellant -- that will be an extremely time-consuming solution.

I don't see how renewables are a path to fossil-fuel use, because I've calculated the ratio of consumption to production of them, and it's something on the order of 1 million. And some fossil fuels are not being produced at rates comparable to their past production.

Renewables were what our civilisation was based on before we started to use fossil fuels and allowed us to have the technological base upon which to exploit fossil fuels.

lpetrich:

Nuclear fusion won't be ready anytime soon -- it's been VERY difficult to construct a fusion reactor that puts out more energy than is necessary to run it.

ITER probably will succeed at that. Fusion whilst it is 30 years away, 30 years ago, has actually been making steady progress towards break-even and if the trends are projected ITER should be able to do it (then DEMO can be an actual fusion power plant).

lpetrich:

And going into outer space? I've calculated how much energy one needs, and it's enormous, especially if one wants to send along all the necessary supplies to build a self-sustaining space colony. Supplies like enough biomass of food plants and animals to sustain having some of it eaten.

If the only thing we had to pay for space launch was energy costs at electricity rates there'd be no problem with affording it.

Although space colonies are more likely to be built using materials from space, not blasted up from Earth so only things that can't be made in space (computers, biomass, maybe nitrogen and carbon if you use moon mining) would need to be blasted up from Earth. Most of the mass of a space colony would be radiation shielding anyway (I also doubt our first space colony would be self-sufficient).

The biggest coal deposits are from the Carboniferous and the Permian, and it's likely because termites evolved in the Triassic and ate all the dead trees that might otherwise have become coal. And much crude oil had formed in Oceanic Anoxic Events, notably in the Mesozoic; there have not been as many in the Cenozoic, especially not recently. OAE's mostly happen during relatiely warm periods ("greenhouse climate"), and we are in a relatively cool period ("icehouse climate").

Nuclear fusion won't be ready anytime soon -- it's been VERY difficult to construct a fusion reactor that puts out more energy than is necessary to run it.

And going into outer space? I've calculated how much energy one needs, and it's enormous, especially if one wants to send along all the necessary supplies to build a self-sustaining space colony. Supplies like enough biomass of food plants and animals to sustain having some of it eaten.

I don't know where bestonnet gets his ideas -- I don't think that I've ever seen anything like them.

What passes for conservatism these days is arguably authoritarianism.

Could you clarify because I can't quite tell what it is you are actually saying and in what way you are using "conservatism"?

I will stop feeding your trolling, since you've done a splendid job at making yourself look ridiculous.

I was going to say the same thing after reading you last post - you keep looking at people like they're just members of larger collectives rather than sovreigns that separate themselves from them. Unless you adjust that mindset there's little more to be said...

More like "why bother washing the car when a little rain can do the job just as well?" The way I see it, our species' ultimate destination is extiction anyways - so we might as well enjoy the ride while we're here.

Nice try, but I don't think anyone is fooled.

I prefer to leave people to their own devices: if they make it so be it, if not it's tough luck for them.

I stand by my assessment and others' that you are in fact sociopathic.

And it's apparent that you still don't get it - no one "deserves" anything as there is no standard regarding what folks are "deserving" or not.

And you don't get your own hypocrisy. This is especially blatant when you claim things like:

I'll admit that chance has played me a favorible hand in some aspects, but I hardly see them as a sign of me getting them because I "deserve" them more than some one else.

and:

...all men are *not* created equal nor are they all equally entitled to resources. The strongest among us have first pick, and going down the line everyone else just has to settle for whatever's left.

Are you really so delusional as to not understand that you are one of "the strongest" based solely on the fact that you were born in the US instead of in Uganda?

With that, I will stop feeding your trolling, since you've done a splendid job at making yourself look ridiculous.

That's like saying, "Who cares if I shoot you in the head and kill you since you might get hit and killed by a car tomorrow."

More like "why bother washing the car when a little rain can do the job just as well?" The way I see it, our species' ultimate destination is extiction anyways - so we might as well enjoy the ride while we're here.

No, we noted that you obviously don't give a flying eff right now about whether younger people (that you know even) die tomorrow or whenever in some horrible plight that you helped happen. This is why we call you a sociopath.

I prefer to leave people to their own devices: if they make it so be it, if not it's tough luck for them. Call me crazy, but I like the idea of having nature root out the weak - such an approach would help solve our overpopulation problems (fewer people = more resources to go around).

And you still think yourself more deserving and better than others simply because you were born here in the US.

And it's apparent that you still don't get it - no one "deserves" anything as there is no standard regarding what folks are "deserving" or not. The whole idea is just a construct designed to make people feel like they have certain things guaranteed to them. People get whatever it is they get based soley on their ability to take whatever's availible in their environment. I'll admit that chance has played me a favorible hand in some aspects, but I hardly see them as a sign of me getting them because I "deserve" them more than some one else.

1. Even if we do make an effort to maintain our ecosystem, that's no guarantee that it won't implode on itself anyway - all it takes is one good meteor strike or supervolcanic eruption or some other such disaster and life as we know it will come to an end regardless of all our futile efforts to keep nature "in balance." To think that we have total control over whether or not the environment will continue to support us or not is nothing short of arrogance.

That's like saying, "Who cares if I shoot you in the head and kill you since you might get hit and killed by a car tomorrow."

2. People can only care about things so long as they are alive - death = inability to care about anything. By the time the next generation comes on the scene, I won't care what they do - not because I'm an insensitive asshole (as certain people perceive me as being), but because I will literally, physically be unable to care what they do or don't do.

Your refusal to note that I'm not talking about after you die, but your callous attitude towards others who are living right now while you yourself are alive is duly noted. Nowhere did anyone say, "How dare you not care about people while you are dead." No, we noted that you obviously don't give a flying eff right now about whether younger people (that you know even) die tomorrow or whenever in some horrible plight that you helped happen. This is why we call you a sociopath.

That is only partially true - yes, some lands have more resources than others yet the fact remains that (a) the amount of resources availible are finite (no matter how many resources there are they will eventually run out) and (b) populations *will* compete for them and those better suited towards taking them *will* get more of resources availible. This is true whether you are born in Africa, the U.S., the Middle East or another goddamn planet.

And you still think yourself more deserving and better than others simply because you were born here in the US. This has nothing to do with evolution and everything to do with your warped version of reality.