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Asteroid Mining and Space Elevators (split from Are billionaires rich enough yet?)

atrib

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I predict that in about 50 years when we have found ways to mine asteroids in space, a new class of trillionaires will emerge that will make our billionaires today look like paupers in comparison. And this will be a very exclusive club with members who have the billions today to fund research into space travel, which will effectively give them a monopoly in this field. But that is a rant for another day.
 

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I predict that in about 50 years when we have found ways to mine asteroids in space, a new class of trillionaires will emerge that will make our billionaires today look like paupers in comparison.
Even at 3% inflation for the next 50 years, Bezos and Musk would not need any increase in real wealth to break into the terabuck club.

Asteroid mining will be very expensive, and probably only feasible to supply any space construction, not to be brought back to Earth. I.e. it will have limited applications for at least a century or more. So I do not think asteroid mining entrepreneurs will make our current billionaires look like paupers.
 
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atrib

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I predict that in about 50 years when we have found ways to mine asteroids in space, a new class of trillionaires will emerge that will make our billionaires today look like paupers in comparison.
Even at 3% inflation for the next 50 years, Bezos and Musk would not need any increase in real wealth to break into the terabuck club.

Asteroid mining will be very expensive, and probably only feasible to supply any space construction, not to be brought back to Earth. I.e. it will have limited applications for at least a century or more. So I do not think asteroid mining entrepreneurs will make our current billionaires look like paupers.
I was obviously speculating. I don't know that we will have evolved the technology to become a spacefaring species in 50 years exploiting asteroids for resources and energy. But if our descendants do take that step, and at some they will have to in order to survive, even if it is many millions of years in the future, the people who control the technology to allow this to happen are going to be the wealthiest people on the planet.
 
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Jimmy Higgins

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I predict that in about 50 years when we have found ways to mine asteroids in space, a new class of trillionaires will emerge that will make our billionaires today look like paupers in comparison.
Even at 3% inflation for the next 50 years, Bezos and Musk would not need any increase in real wealth to break into the terabuck club.

Asteroid mining will be very expensive, and probably only feasible to supply any space construction, not to be brought back to Earth. I.e. it will have limited applications for at least a century or more. So I do not think asteroid mining entrepreneurs will make our current billionaires look like paupers.
I was obviously speculating. I don't know that we will have evolved the technology to become a spacefaring species in 50 years exploiting asteroids for resources and energy. But if our descendants do take that step, and at some they will have to in order to survive, even if it is many millions of years in the future, the people who control the technology to allow this to happen are going to be the wealthiest people on the planet.
Oh the irony, the cost to mine asteroids will be extraordinary! First you need to get to it, then somehow get the metals, then somehow get that to Earth. So, a lot of difficult things.

That said, once that tech is there, asteroid mining will become like diamonds. Precious metals aren't as precious if they aren't as rare.
 

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Oh the irony, the cost to mine asteroids will be extraordinary! First you need to get to it, then somehow get the metals, then somehow get that to Earth. So, a lot of difficult things.

That said, once that tech is there, asteroid mining will become like diamonds. Precious metals aren't as precious if they aren't as rare.
There's little worth shipping from the asteroids to Earth. However, using the material as raw materials in space is quite another matter. And there are space-manufactured products that are worth shipping to Earth. We have ships that are inherently unsinkable--they're lighter than their volume, push them underwater and they'll pop back up. However, the materials are weak, you can't make a big ship and even the small ones can be damaged enough to sink. In microgravity you can make metal foam--pound for pound stronger than the base material and it can be made to float. Unsinkable ships in any size.
 

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Generally, I am rooted in both ancient Epicurean and ancient Pyrrhonist sentiments, although I am somewhat sympathetic toward the intentions behind ancient Cynicism.
On shipping material mined from asteroids to Earth, umm...actually, my thinking is that robotic unmanned barges could be run very cheaply. I mean if you are just talking about shipping a large quantity of precious metal to Earth, then you only have to worry about lift-off and getting it on just the right vector so that it eventually makes a reasonably slow approach to Earth or its moon. You do not have to constantly propel the shipment all the way through the solar system. Once you had established an economy of scale, the shipping cost would end up being rather cheap, maybe even cheaper than shipping by sea. We are talking about a relatively frictionless environment.
 

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On shipping material mined from asteroids to Earth, umm...actually, my thinking is that robotic unmanned barges could be run very cheaply. I mean if you are just talking about shipping a large quantity of precious metal to Earth, then you only have to worry about lift-off and getting it on just the right vector so that it eventually makes a reasonably slow approach to Earth or its moon. You do not have to constantly propel the shipment all the way through the solar system. Once you had established an economy of scale, the shipping cost would end up being rather cheap, maybe even cheaper than shipping by sea. We are talking about a relatively frictionless environment.
The problem is getting it down to the surface in a usable and accessible condition, without harming the environment or the local population.

Meteors bring between 40 and 80 thousand tonnes of material to Earth each year right now; But it mostly arrives as dust, which is useless, and what arrives in larger pieces either turns to dust on re-entry, rendering it useless, or stays in one lump, rendering it highly dangerous.

Getting stuff down in remote areas is probably fairly easy to arrange, though it requires very precise control both to prevent loss (to burnup or to deflection off the atmosphere), but ore in remote areas we already have lots of, without the hassle of going to space for it.

What we really need is a space elevator.
 

SigmatheZeta

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Generally, I am rooted in both ancient Epicurean and ancient Pyrrhonist sentiments, although I am somewhat sympathetic toward the intentions behind ancient Cynicism.
On shipping material mined from asteroids to Earth, umm...actually, my thinking is that robotic unmanned barges could be run very cheaply. I mean if you are just talking about shipping a large quantity of precious metal to Earth, then you only have to worry about lift-off and getting it on just the right vector so that it eventually makes a reasonably slow approach to Earth or its moon. You do not have to constantly propel the shipment all the way through the solar system. Once you had established an economy of scale, the shipping cost would end up being rather cheap, maybe even cheaper than shipping by sea. We are talking about a relatively frictionless environment.
The problem is getting it down to the surface in a usable and accessible condition, without harming the environment or the local population.

Meteors bring between 40 and 80 thousand tonnes of material to Earth each year right now; But it mostly arrives as dust, which is useless, and what arrives in larger pieces either turns to dust on re-entry, rendering it useless, or stays in one lump, rendering it highly dangerous.

Getting stuff down in remote areas is probably fairly easy to arrange, though it requires very precise control both to prevent loss (to burnup or to deflection off the atmosphere), but ore in remote areas we already have lots of, without the hassle of going to space for it.

What we really need is a space elevator.
A lunar elevator would be more feasible if you wanted to go that route. Think about it: the moon always has the same face toward Earth. If we could establish a line between the surface of the moon and a station set up in a low orbit in the atmosphere of Earth (maybe using solar powered propulsion to hold it in its proper orbit), then it would be reasonable enough to design a cargo plane that could travel between the station and the planet's surface.
 

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A lunar elevator would be more feasible if you wanted to go that route. Think about it: the moon always has the same face toward Earth. If we could establish a line between the surface of the moon and a station set up in a low orbit in the atmosphere of Earth (maybe using solar powered propulsion to hold it in its proper orbit), then it would be reasonable enough to design a cargo plane that could travel between the station and the planet's surface.
How long a line will you use? The distance from the moon to the earth varies by 43,000 km every two weeks.
 

Bomb#20

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What we really need is a space elevator.
What's a space elevator? It's just some physical object capable of holding a "climber" vehicle up against gravity, all the way to space, so you can go up as slowly as you like instead of using a rocket with a specific impulse measured in minutes. So why not build a space elevator? Because (a) if we built one we'd need to use super-strong futuristic high-tech materials we don't know how to make, and (b) it would be tall and skinny and therefore have about a million potential failure points and attack vulnerabilities, and (c) it would probably cost more than any resulting revenue stream could justify, and (d) we've already got one.

MontyPythonAndTheHolyGrail-5hNjXzBz-subtitled.jpg


It's low-tech, it's free, and it's indestructible. It's called "the atmosphere". These guys are working on the climber for it.
 

SigmatheZeta

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Generally, I am rooted in both ancient Epicurean and ancient Pyrrhonist sentiments, although I am somewhat sympathetic toward the intentions behind ancient Cynicism.
A lunar elevator would be more feasible if you wanted to go that route. Think about it: the moon always has the same face toward Earth. If we could establish a line between the surface of the moon and a station set up in a low orbit in the atmosphere of Earth (maybe using solar powered propulsion to hold it in its proper orbit), then it would be reasonable enough to design a cargo plane that could travel between the station and the planet's surface.
How long a line will you use? The distance from the moon to the earth varies by 43,000 km every two weeks.
Who, me? I am not an engineer. I had only heard of the proposal before, but it was made by someone that really was an engineer.
 

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A lunar elevator would be more feasible if you wanted to go that route. Think about it: the moon always has the same face toward Earth. If we could establish a line between the surface of the moon and a station set up in a low orbit in the atmosphere of Earth (maybe using solar powered propulsion to hold it in its proper orbit), then it would be reasonable enough to design a cargo plane that could travel between the station and the planet's surface.
How long a line will you use? The distance from the moon to the earth varies by 43,000 km every two weeks.
That's not a drama, you just need a winch on the Moon to wind in and pay out line as required.

And a spool large enough to hold that 43,000km of line.

And a motor capable of pulling in the line at a maximum rate of a couple of hundred km/h.
 

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What's a space elevator? It's just some physical object capable of holding a "climber" vehicle up against gravity, all the way to space, so you can go up as slowly as you like instead of using a rocket with a specific impulse measured in minutes.
No, that's not all a space elevator is.

Orbit isn't difficult to reach because it's far; It's difficult to reach because it's fast.

A space elevator gives the stuff it lifts the lateral speed necessary to stay in orbit. Any system that fails to do this cannot launch stuff into orbit; You might get your satellite to an arbitrarily high altitude by lifting against the atmosphere, but if you stop supporting it, it will just become an instant meteor.

The atmosphere simply doesn't extend far enough out to get you anywhere near to a point where orbital velocity is close to zero ground speed - aka Geostationary Orbit.

I suspect you already know this.

https://what-if.xkcd.com/58/

https://what-if.xkcd.com/126/
 

Loren Pechtel

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On shipping material mined from asteroids to Earth, umm...actually, my thinking is that robotic unmanned barges could be run very cheaply. I mean if you are just talking about shipping a large quantity of precious metal to Earth, then you only have to worry about lift-off and getting it on just the right vector so that it eventually makes a reasonably slow approach to Earth or its moon. You do not have to constantly propel the shipment all the way through the solar system. Once you had established an economy of scale, the shipping cost would end up being rather cheap, maybe even cheaper than shipping by sea. We are talking about a relatively frictionless environment.
The problem is getting it down to the surface in a usable and accessible condition, without harming the environment or the local population.

Meteors bring between 40 and 80 thousand tonnes of material to Earth each year right now; But it mostly arrives as dust, which is useless, and what arrives in larger pieces either turns to dust on re-entry, rendering it useless, or stays in one lump, rendering it highly dangerous.

Getting stuff down in remote areas is probably fairly easy to arrange, though it requires very precise control both to prevent loss (to burnup or to deflection off the atmosphere), but ore in remote areas we already have lots of, without the hassle of going to space for it.

What we really need is a space elevator.

To get it down you take the good stuff, turn it into foam so it floats. Then wrap that in foamed slag. Drop it into a big patch of ocean. The drop zone is limited to the retrieval ships only, both for safety (you had better be tied in with the tracking guys!) and to avoid piracy. Since it's a foam even if it breaks on impact (terminal velocity will be pretty high) the pieces just float.
 

Loren Pechtel

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A lunar elevator would be more feasible if you wanted to go that route. Think about it: the moon always has the same face toward Earth. If we could establish a line between the surface of the moon and a station set up in a low orbit in the atmosphere of Earth (maybe using solar powered propulsion to hold it in its proper orbit), then it would be reasonable enough to design a cargo plane that could travel between the station and the planet's surface.
Can't be done--look at the actual orbit of the moon.

A cable like you envision could actually be done off Phobos for getting to Mars. (It can't throw to Martian escape, but it can throw to another cable on Deimos--and that one can throw to Earth.)
 

Loren Pechtel

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A lunar elevator would be more feasible if you wanted to go that route. Think about it: the moon always has the same face toward Earth. If we could establish a line between the surface of the moon and a station set up in a low orbit in the atmosphere of Earth (maybe using solar powered propulsion to hold it in its proper orbit), then it would be reasonable enough to design a cargo plane that could travel between the station and the planet's surface.
How long a line will you use? The distance from the moon to the earth varies by 43,000 km every two weeks.
That's not a drama, you just need a winch on the Moon to wind in and pay out line as required.

And a spool large enough to hold that 43,000km of line.

And a motor capable of pulling in the line at a maximum rate of a couple of hundred km/h.
And some way of handling the lunar libration.
 

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A lunar elevator would be more feasible if you wanted to go that route. Think about it: the moon always has the same face toward Earth. If we could establish a line between the surface of the moon and a station set up in a low orbit in the atmosphere of Earth (maybe using solar powered propulsion to hold it in its proper orbit), then it would be reasonable enough to design a cargo plane that could travel between the station and the planet's surface.
How long a line will you use? The distance from the moon to the earth varies by 43,000 km every two weeks.
That's not a drama, you just need a winch on the Moon to wind in and pay out line as required.

And a spool large enough to hold that 43,000km of line.

And a motor capable of pulling in the line at a maximum rate of a couple of hundred km/h.
I suspect you would need a lot more than just 43K km of line. The land point on Earth would be stationary while the moon moves away and towards that point.

I hope we've had enough of this science fiction derail.
 

Loren Pechtel

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A lunar elevator would be more feasible if you wanted to go that route. Think about it: the moon always has the same face toward Earth. If we could establish a line between the surface of the moon and a station set up in a low orbit in the atmosphere of Earth (maybe using solar powered propulsion to hold it in its proper orbit), then it would be reasonable enough to design a cargo plane that could travel between the station and the planet's surface.
How long a line will you use? The distance from the moon to the earth varies by 43,000 km every two weeks.
That's not a drama, you just need a winch on the Moon to wind in and pay out line as required.

And a spool large enough to hold that 43,000km of line.

And a motor capable of pulling in the line at a maximum rate of a couple of hundred km/h.
I suspect you would need a lot more than just 43K km of line. The land point on Earth would be stationary while the moon moves away and towards that point.

I hope we've had enough of this science fiction derail.
43K km of line that has to be rolled and unrolled, there's a lot more that would never be rolled. It's completely impractical.
 

Bomb#20

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What's a space elevator? It's just some physical object capable of holding a "climber" vehicle up against gravity, all the way to space, so you can go up as slowly as you like instead of using a rocket with a specific impulse measured in minutes.
No, that's not all a space elevator is.

Orbit isn't difficult to reach because it's far; It's difficult to reach because it's fast.
Sorry, should have said "all the way to space and orbital speed", and should have said "It's low-tech, it's free, it's indestructible, and it isn't tall and skinny."

A space elevator gives the stuff it lifts the lateral speed necessary to stay in orbit.
But it only needs to do that if it's tall and skinny. You'll fall to the ground as soon as you start accelerating laterally if you don't have orbital speed right from the get-go, because as soon as you start accelerating laterally you're not being supported any more, because you're not on the elevator any more, because it's tall and skinny. That's the only reason you have to ride it all the way up to 35,000 km -- that's where the elevator is going at orbital speed. But if instead the elevator is short and wide, then you can start accelerating laterally wherever you please, and you'll still be on the elevator, still being supported against gravity while you're below orbital speed. So you can accelerate up to orbital speed as slowly as you like, same as you can go up as slowly as you like. The outfit I linked to is designing aircraft to go up to where the atmosphere is thin enough for an ion drive to work, and then accelerate laterally up to orbital speed. The drive is vastly more efficient than a chemical rocket but it doesn't deliver the gees to hold itself up against gravity while it's doing it. Holding it up against gravity is the atmosphere's job.

Seems to me if Bezos wants to leapfrog Musk and mine asteroids first and become the first trillionaire, he could probably finance the R&D for less than Musk is going to pay for Twitter.
 

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A lunar elevator would be more feasible if you wanted to go that route. Think about it: the moon always has the same face toward Earth. If we could establish a line between the surface of the moon and a station set up in a low orbit in the atmosphere of Earth (maybe using solar powered propulsion to hold it in its proper orbit), then it would be reasonable enough to design a cargo plane that could travel between the station and the planet's surface.
Can't be done--look at the actual orbit of the moon.

A cable like you envision could actually be done off Phobos for getting to Mars. (It can't throw to Martian escape, but it can throw to another cable on Deimos--and that one can throw to Earth.)
You could do it (assuming miracle fiber) above the equator at >geostationary distances but you’d have to continue to add energy to the high end or the orbit would decay under weight. So ultimately you wouldn’t get rid of, or significantly reduce the absolute energy needed to lift to LEO, except the air resistance.
And you could :rolleyesa: use a tethered lighter than air launch platform to counter most of that …

:shrug:
 

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Whether or not humanity can build a space elevetor, "the market" cannot build enough space elevators so that there will be anything but an oligopoly or an outright monopoly.

Ditto rockets.

It makes sense for the state to some things.
 

Loren Pechtel

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A lunar elevator would be more feasible if you wanted to go that route. Think about it: the moon always has the same face toward Earth. If we could establish a line between the surface of the moon and a station set up in a low orbit in the atmosphere of Earth (maybe using solar powered propulsion to hold it in its proper orbit), then it would be reasonable enough to design a cargo plane that could travel between the station and the planet's surface.
Can't be done--look at the actual orbit of the moon.

A cable like you envision could actually be done off Phobos for getting to Mars. (It can't throw to Martian escape, but it can throw to another cable on Deimos--and that one can throw to Earth.)
You could do it (assuming miracle fiber) above the equator at >geostationary distances but you’d have to continue to add energy to the high end or the orbit would decay under weight. So ultimately you wouldn’t get rid of, or significantly reduce the absolute energy needed to lift to LEO, except the air resistance.
And you could :rolleyesa: use a tethered lighter than air launch platform to counter most of that …

:shrug:
Assuming a miracle fiber you tether it to the Earth and put enough mass above geosync that it's always under tension. Now it only costs electricity, nothing needs to be done to keep it in orbit.
 

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A lunar elevator would be more feasible if you wanted to go that route. Think about it: the moon always has the same face toward Earth. If we could establish a line between the surface of the moon and a station set up in a low orbit in the atmosphere of Earth (maybe using solar powered propulsion to hold it in its proper orbit), then it would be reasonable enough to design a cargo plane that could travel between the station and the planet's surface.
Can't be done--look at the actual orbit of the moon.

A cable like you envision could actually be done off Phobos for getting to Mars. (It can't throw to Martian escape, but it can throw to another cable on Deimos--and that one can throw to Earth.)
You could do it (assuming miracle fiber) above the equator at >geostationary distances but you’d have to continue to add energy to the high end or the orbit would decay under weight. So ultimately you wouldn’t get rid of, or significantly reduce the absolute energy needed to lift to LEO, except the air resistance.
And you could :rolleyesa: use a tethered lighter than air launch platform to counter most of that …

:shrug:
Assuming a miracle fiber you tether it to the Earth and put enough mass above geosync that it's always under tension. Now it only costs electricity, nothing needs to be done to keep it in orbit.
I was thinking about that … keyword miracle. If it’s strong enough and long enough, like halfway to the moon, a ten pound weight at the end would be sufficient to haul tons … but adding weight would still degrade the orbit (unless I’m missing something).
 

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A lunar elevator would be more feasible if you wanted to go that route. Think about it: the moon always has the same face toward Earth. If we could establish a line between the surface of the moon and a station set up in a low orbit in the atmosphere of Earth (maybe using solar powered propulsion to hold it in its proper orbit), then it would be reasonable enough to design a cargo plane that could travel between the station and the planet's surface.
Can't be done--look at the actual orbit of the moon.

A cable like you envision could actually be done off Phobos for getting to Mars. (It can't throw to Martian escape, but it can throw to another cable on Deimos--and that one can throw to Earth.)
You could do it (assuming miracle fiber) above the equator at >geostationary distances but you’d have to continue to add energy to the high end or the orbit would decay under weight. So ultimately you wouldn’t get rid of, or significantly reduce the absolute energy needed to lift to LEO, except the air resistance.
And you could :rolleyesa: use a tethered lighter than air launch platform to counter most of that …

:shrug:
Assuming a miracle fiber you tether it to the Earth and put enough mass above geosync that it's always under tension. Now it only costs electricity, nothing needs to be done to keep it in orbit.
I was thinking about that … keyword miracle. If it’s strong enough and long enough, like halfway to the moon, a ten pound weight at the end would be sufficient to haul tons … but adding weight would still degrade the orbit (unless I’m missing something).
As long as the centre of mass of the entire system, including counterweight, is beyond geostationary orbit, the whole thing is always in tension. Breaking the cable would cause the part above the break to fly off into space, not fall back to Earth.
 

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I do not see it becoming economically feasible considering the total cost of ground support, launch and travel, vehicle, mining, and returning useful quantities of minerals.

Dollars/kilogram of a mineral on the ground ready for preocessing.

In Heinlein's Moon Is A Harsh Mistress lunar colonists send materials to Earth using magnetic rail launch as I rember. The containers splash down in the ocean.

Eco wise we need to learn to live within limits. The next area for mining is the deep ocean floor. There is no legal claim, Russia dropped Russian flags on the sea floor where there are resources.

As to a teher, I would think rotation would be needed to keep the cable taught.
 

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I do not see it becoming economically feasible considering the total cost of ground support, launch and travel, vehicle, mining, and returning useful quantities of minerals.
^^^^ This ^^^^

Going out to space to mine is something you do if you're running out of minerals on your home planet. We aren't. In constant dollars, earth-mined minerals just keep getting cheaper and cheaper.
 

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I was thinking about that … keyword miracle. If it’s strong enough and long enough, like halfway to the moon, a ten pound weight at the end would be sufficient to haul tons … but adding weight would still degrade the orbit (unless I’m missing something).
You're missing something--all mass beyond geosync is moving faster than orbital velocity, it pulls outward. So long as you don't hang too much stuff on it it's going to go round and round, tossing packages on transfer orbits to the closer planets. (This is paid for with Earth's rotation.) IIRC without weights it's something like 170K km long assuming a cable tapered so as to experience equal strain across it's entire length.

There are two big problems:

1) We don't have strong enough stuff. Note that there are three places we can build a cable with current tech: Luna, Phobos, and Deimos. Luna is limited to a single cable pointing Earthward.

2) Debris impacts.
 

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I woud think those pesky satelites and the ISS could get in the way of an Earth tether beyond LEO.

In the 90s I went to a local Mars Society presentaion on the space elevator project. It never happened. In following years it was said all NASA was really interested in was the carbon fiber technology. Nano tubes.

In any case the teher material mayerial and a demonstration cable has yet to be made AFAIK.
 

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I was thinking about that … keyword miracle. If it’s strong enough and long enough, like halfway to the moon, a ten pound weight at the end would be sufficient to haul tons … but adding weight would still degrade the orbit (unless I’m missing something).
You're missing something--all mass beyond geosync is moving faster than orbital velocity, it pulls outward. So long as you don't hang too much stuff on it it's going to go round and round, tossing packages on transfer orbits to the closer planets. (This is paid for with Earth's rotation.) IIRC without weights it's something like 170K km long assuming a cable tapered so as to experience equal strain across it's entire length.

There are two big problems:

1) We don't have strong enough stuff. Note that there are three places we can build a cable with current tech: Luna, Phobos, and Deimos. Luna is limited to a single cable pointing Earthward.

2) Debris impacts.
Im not missing that. If you add “enough weight” it will come crashing down instantly as soon as the c.o.g. of the whole system lies inside geosynchronous height. Before that though, you have to accelerate the counterweight to several times Leo orbital velocity, if it’s goin to remain geosynchronous at say 40,000 miles away.
When you add weight, the drag will slightly (or greatly if it’s enough weight) alter its orbit. The effect will compound until the orbit decays and its orbital period is less than 24 hrs … it wraps around the earth and slices it in half like a melon.
Okay I made up that last part.
 

skepticalbip

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I was thinking about that … keyword miracle. If it’s strong enough and long enough, like halfway to the moon, a ten pound weight at the end would be sufficient to haul tons … but adding weight would still degrade the orbit (unless I’m missing something).
You're missing something--all mass beyond geosync is moving faster than orbital velocity, it pulls outward. So long as you don't hang too much stuff on it it's going to go round and round, tossing packages on transfer orbits to the closer planets. (This is paid for with Earth's rotation.) IIRC without weights it's something like 170K km long assuming a cable tapered so as to experience equal strain across it's entire length.

There are two big problems:

1) We don't have strong enough stuff. Note that there are three places we can build a cable with current tech: Luna, Phobos, and Deimos. Luna is limited to a single cable pointing Earthward.

2) Debris impacts.
And then, lifting a payload from the surface of any body with no atmosphere is much more practically done with a linear accelerator on the surface.
 

bilby

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When you add weight, the drag will slightly (or greatly if it’s enough weight) alter its orbit.
I assume that by 'weight', you mean 'mass'; But I am completely stumped about what you mean by 'drag'; There's no significant drag outside Low Earth Orbit, and even at LEO, drag is minimal. Drag is a characteristic of intra-atmospheric operations, and doesn't apply to the space end of a space elevator.
 

steve_bank

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Economics is why I think the probability of being visited by ET is very low.

A space faring civilization as depicted on Star Trek series would be an enormous economic undertaking. Even in a dictatorship like Egyptian Pharaohs builng pyramids involves economics. Labor, food, and materials.

If something is econmcally viable and it results in a cheaper way to aquire something, someone will do it. The new planned commercial spcae staion from what I read will make money in the long run. Companies including NASA are willing to apy for space pon the staion. There are probaly many globally who can affotd a joy ride to a space station.

If there were an economic need fora mineral asteroid ming woud be commercially funded.

The commercialization of LEO and eventually the Moon is what will open up space exploration. The profit motive.
 

Canard DuJour

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China's economic liberalisation resulted in more billionaires and less dire poverty.

Russia's economic liberalisation resulted in more billionaires and more dire poverty.

Globally, economic liberalisation resulted in more billionaires and slower economic growth.
Slower growth + more inequality = most folks worse off than they'd otherwise have been.

China did its own version of economic liberalisation, which was not western neoliberalism and actually quite authoritarian.

Russia accepted the western neoliberal model which has made most folks in the west worse off, pushed millions of Russians into dire poverty and resulted in an authoritarian/nationalist backlash - AKA Putin.

I won't point out the Western parallels with Trump, Brexit, Le Pen.. oops I have pointed it out.

As others point out, the billionaires are symptom, not disease.
 

steve_bank

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China's economic liberalisation resulted in more billionaires and less dire poverty.

Russia's economic liberalisation resulted in more billionaires and more dire poverty.

Globally, economic liberalisation resulted in more billionaires and slower economic growth.
Slower growth + more inequality = most folks worse off than they'd otherwise have been.

China did its own version of economic liberalisation, which was not western neoliberalism and actually quite authoritarian.

Russia accepted the western neoliberal model which has made most folks in the west worse off, pushed millions of Russians into dire poverty and resulted in an authoritarian/nationalist backlash - AKA Putin.

I won't point out the Western parallels with Trump, Brexit, Le Pen.. oops I have pointed it out.

As others point out, the billionaires are symptom, not disease.
Off topic. However Russia adopted a mix of Stalinism and the Nazi kleptocracy. AKABoris Yeltsin followed by Vladimir Putin. Liberal democracy lasted a few years after the Soviet collapse.

China while still ruled by the CCP communist in name identifies itself as a socialist state. It makes a point of declaring it is not like the west and liberal democracy which it rejects as a matter of policy.
 

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I woud think those pesky satelites and the ISS could get in the way of an Earth tether beyond LEO.

In the 90s I went to a local Mars Society presentaion on the space elevator project. It never happened. In following years it was said all NASA was really interested in was the carbon fiber technology. Nano tubes.

In any case the teher material mayerial and a demonstration cable has yet to be made AFAIK.

Yeah, you can have elevators or you can have satellites, doing both is not viable. If you want space-based stuff and elevators you have to go with orbital rings. I question whether satellites are sustainable for the long term anyway, though--Kessler syndrome.
 

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Im not missing that. If you add “enough weight” it will come crashing down instantly as soon as the c.o.g. of the whole system lies inside geosynchronous height. Before that though, you have to accelerate the counterweight to several times Leo orbital velocity, if it’s goin to remain geosynchronous at say 40,000 miles away.
When you add weight, the drag will slightly (or greatly if it’s enough weight) alter its orbit. The effect will compound until the orbit decays and its orbital period is less than 24 hrs … it wraps around the earth and slices it in half like a melon.
Okay I made up that last part.
Keeping the center of mass outside geosync is basic elevator design, it's not going to come down.
 

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Im not missing that. If you add “enough weight” it will come crashing down instantly as soon as the c.o.g. of the whole system lies inside geosynchronous height. Before that though, you have to accelerate the counterweight to several times Leo orbital velocity, if it’s goin to remain geosynchronous at say 40,000 miles away.
When you add weight, the drag will slightly (or greatly if it’s enough weight) alter its orbit. The effect will compound until the orbit decays and its orbital period is less than 24 hrs … it wraps around the earth and slices it in half like a melon.
Okay I made up that last part.
Keeping the center of mass outside geosync is basic elevator design, it's not going to come down.
Correct. The large mass outside geosynchronous orbit would fly off on a tangent if the tether snapped. The physics is similar to the physics of the Olympics' hammer throw. It is the 'centrifugal force' of that distant mass that keeps the tether taut and it is the Earth rotating faster than the natural orbital speed of a mass that distant that transfers energy to make that mass have a greater angular velocity than orbital speed at that distance.
 

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Im not missing that. If you add “enough weight” it will come crashing down instantly as soon as the c.o.g. of the whole system lies inside geosynchronous height. Before that though, you have to accelerate the counterweight to several times Leo orbital velocity, if it’s goin to remain geosynchronous at say 40,000 miles away.
When you add weight, the drag will slightly (or greatly if it’s enough weight) alter its orbit. The effect will compound until the orbit decays and its orbital period is less than 24 hrs … it wraps around the earth and slices it in half like a melon.
Okay I made up that last part.
Keeping the center of mass outside geosync is basic elevator design, it's not going to come down.
Correct. The large mass outside geosynchronous orbit would fly off on a tangent if the tether snapped. The physics is similar to the physics of the Olympics' hammer throw. It is the 'centrifugal force' of that distant mass that keeps the tether taut and it is the Earth rotating faster than the natural orbital speed of a mass that distant that transfers energy to make that mass have a greater angular velocity than orbital speed at that distance.
There's no need for scare quotes.

Centrifugal force is a perfectly good force, and one that is encountered in a wide range of situations (including the one under discussion). Insisting on the nonexistence of the mandatory equal-and-opposite of centripetal force is just silly.

IMG_5476.PNG
 
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