Question Construction in orbit

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Feb 22, 2021
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Please read my replies.

"You can also send asteroid pieces to earth for sale"

Would 2 cents a ton be a fair price?

Cat :)
There are so many other uses for asteroids, and you apologize to something like that.

2 cents for a tone? Where did you get this price? For ordinary people, 100 dollars per kilogram / piece. At auctions, you could sell such an asteroid for a lot more.
 

Catastrophe

There never was a good war, or a bad peace
Feb 18, 2020
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That is entirely my point.

Can't be such a good idea if it requires selling bits off cheap (or even expensively),

Even at $100/gm might not yield a profit.

Cat :)
 
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Feb 22, 2021
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That is entirely my point.

Can't be such a good idea if it requires selling bits off cheap (or even expensively),

Even at $100/gm might not yield a profit.

Cat :)
Ok, but there are also other things for which such an asteroid is good to bring in whole or in pieces
 

Catastrophe

There never was a good war, or a bad peace
Feb 18, 2020
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"Ok, but there are also other things for which such an asteroid is good to bring in whole or in pieces "

Like . . . . . . . . . silicates?

And in replying about iron and other metals please estimate the cost per kg in getting them here or to processable location.

Cat :)
 
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Jun 1, 2020
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Perhaps orbit-crossing asteroids would be easier to exploit. There are over 12,000 Apollo asteroids, plus a lesser number o Aten asteroids.

Assuming more for Mars, my guess is that it would be best to send processed ores to Phobos, which requires much less deceleration fuel.
 
Feb 22, 2021
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"Ok, but there are also other things for which such an asteroid is good to bring in whole or in pieces "

Like . . . . . . . . . silicates?

And in replying about iron and other metals please estimate the cost per kg in getting them here or to processable location.

Cat :)
https://www.reddit.com/r/space/comments/1ktjfi View: https://www.reddit.com/r/space/comments/1ktjfi/deltav_map_of_the_solar_system/


I can't calculate it, but looking at Wikipedia and also on the deltaV map of the solar system, it seems that it will be quite profitable.

It can be mentioned that when building in orbit, we are not limited by the shape of the ship (and the number of engines), but by its mass.

And if it succeeds, the one who does it will have a huge advantage over the others.
 
Feb 22, 2021
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I think less DeltaV is needed to reach the asteroid and bring it into Earth's orbit than to go to Mars

DeltaV is a measure of force that is needed to change the orbit / flight trajectories in space / orbit
 
Jun 1, 2020
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Please explain what this Delta-V is all about. Special position of Earth?
This article has a very helpful illustration (first one). These are Hohmann transfer orbital impulses. As I understand it, and I might not...

1)Start while in orbit around the planet.
2) Fire engines at the ideal orbital point to produce a trajectory achieving an elliptical orbit where the apsis reaches the orbit of the destination planet.
3). At this point, fire engines to proceed to planet.

Not the fastest trajectory but the most fuel efficient, apparently.

It‘s unclear to me if a Moon trajectory is incorporated in this delta-Vs. If not, then adding all the delta-Vs along the path seems to give the minimum impulse energy required.
 
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Dec 29, 2019
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I think the problem is constructing anything in space makes it a lot more expensive, especially if a crew is required. It is much easier and more cost effective to build modular components that don't need astronauts to assemble than to establish a safe working environment for astronauts in order to have them do it.

I can't see astronauts doing things by glove ever being up to the exacting requirements technology in space demands; dexterity in a space suit is, at best, a slow and arduous undertaking. Like it or not, machines do space better.

I also think the only purpose in doing anything in space that really counts will be in aid of Earth and it will have to do so through conventional economic means; ie deliver tangible returns to investors - Earth investors, because there aren't any other sort.

Something of value has to come back to Earth - in excess of what is spent (by Earth) on getting it. I think if we can't import bulk commodities like iron and nickel from space at comparable cost to Earth sources then asteroid mining is unlikely to thrive. Nickel is currently US$19,000 per metric ton. With massive growth in battery use that will only go higher. High nickel taenite, up to 65% Ni, would be worth over $12,000 per ton - and sellable as is, unrefined, for making high nickel steel alloys. But refined would yield almost as much worth of precious metals again. By any Earthly standard a commodity that exists in huge quantities, is worth $12,000 per ton without refining is better than any gold mine. And if something that valuable isn't enough then I think we should stop calling asteroids an economic opportunity.
 
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Jun 1, 2020
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There may still be big investors betting in long term gains that may arise off-world. Mining anywhere but Earth has many cost advantages beyond engineering costs. Tesla, for instance, would have lost money last year if not for their selling of their carbon credits.

Such side issues are part of the reason for the $12,000 amount, of course, but if investors see brighter, or less dark, horizons elsewhere, they won’t wait for you to build it before they come.
 

Catastrophe

There never was a good war, or a bad peace
Feb 18, 2020
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OK, but the costs are, of course, going to vary greatly depending on location (e.g., Mars vs NEA) and which metal/ore and parameters of concentration. contaminants, etcetera.

Cat :)
 
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Feb 22, 2021
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OK, but the costs are, of course, going to vary greatly depending on location (e.g., Mars vs NEA) and which metal/ore and parameters of concentration. contaminants, etcetera.

Cat :)

At this point, we give up on aluminum because we take it out and fold it into the upholstery

I wonder if 5-10 cm steel would be good for making ships.
 
Mar 5, 2020
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Space infrastructure is best sold as an insurance policy.

Without that infrastructure an interstellar asteroid impact could send us back to the stone age…again.

Funding and launching the entire planetary defense system from Earth for perpetuity (the existence of the human race) does not make sense.

You also underestimate that rare human quality, ingenuity. Occasionally humans can randomly bang on the right typewriter keys, in the right order, and produce something new that works.

Oh, an sacrificing the economic priests (to any gods of your choosing) who control and suppress terrestrial science wouldn’t hurt.

The universe is already trying to kill you. Don’t let secret science make it easier.
 
Dec 29, 2019
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Space infrastructure is best sold as an insurance policy.

Without that infrastructure an interstellar asteroid impact could send us back to the stone age…again.

Funding and launching the entire planetary defense system from Earth for perpetuity (the existence of the human race) does not make sense.

You also underestimate that rare human quality, ingenuity. Occasionally humans can randomly bang on the right typewriter keys, in the right order, and produce something new that works.

Oh, an sacrificing the economic priests (to any gods of your choosing) who control and suppress terrestrial science wouldn’t hurt.

The universe is already trying to kill you. Don’t let secret science make it easier.
I think a planetary defense system is a workable motive for large scale taxpayer funded space programs - perhaps the best justification of all - but "Lifeboats" or "Earth 2's" are not. I think the scale of pre-investment to make a self-reliant space economy is far too great - and will likely have much higher risks of non-survivable disasters than Earth. Space dreams have to be for the benefit of Earth through being economically viable or they will fail.

I also think the technologies and solutions needed for any hoped for space economy are going to be the product of a healthy, wealthy Earth economy; individual ingenuity will be useless without it. Thriving (ie commercially profitable) aerospace industries can spend time and money on advancing space technology; failing ones cannot. No individual can do it. Unless you propose an end to free enterprise and use authoritarian planned control (USSR built up a large and advanced military successfully like that, so it can work, sort of) , economic viability will continue to be the bottom line.
 
Mar 5, 2020
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Your typical hardware store would be a treasury in the Greek dark ages.

Imagine trying to make conductive wire in 1000 BC.

You are correct that without an intact and innovative economy even a genius has little effect.

The current American military budget would have viable colonies (asteroids or Mars) within 30 years. You just need America’s rulers to accept an outplacement intervention.
 
Dec 29, 2019
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The current American military budget would have viable colonies (asteroids or Mars) within 30 years. You just need America’s rulers to accept an outplacement intervention.
I'm afraid the American military budget will continue to be used for the US military, not for establishing space colonies. A long term global meteor defense program and budget will probably overlap a lot but is more likely to be international, in addition, not instead. It would keep space programs active without the pesky need to pay for them to pay for themselves - although if it stops a big meteor it will pay for itself. Could still be difficult to get sufficient motivation - 1 in 10,000 year impacts make good odds for NOT being hit any time soon; people are accepting a high chance of global warming being globally devastating without that much fuss. A significant impact would probably have to happen to get attention and support.

As a general observation defense forces have primary duties to protect their nation and citizens; there may well be contingency plans that include some kind of Strangelove option but the bunkers that make that possible are a consequence of determination to maintain military capabilities for scenarios well short of their nation being destroyed, in order to prevent or respond to extreme scenarios. Because the bunkers are already there the Strangelove option is not so hard to include, quietly, by the command hierarchy, on the basis of need to protect the command hierarchy.

I don't think space colonies can piggyback a Stangelove option into their objectives like that - I don't think it can be a primary objective and be viable. Other, more compelling reasons are needed. And I keep coming back to the size and capabilities a space economy needs to be self reliant - and how to grow it sufficiently in the absence of tangible returns on investment; these kinds of "higher" objectives won't matter if the space economy cannot support itself.

Space is certainly of great military significance and space programs exist in large part because of that - but near term it is entirely about Near Earth space concerns, for communication and observation, command and control. Should "Peaceful use of Space" agreements fail - and I'm not sure they are being upheld in practice right now, let alone spirit - that would include weaponising. One space battle and a Kessler cascade could end space ambitions for good - not good.
 
Feb 22, 2021
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The only problem with the conquest of space is that we are divided into countries and we do not cooperate with each other.
And when we cooperate, we try to get profit for our own people and not for people on Earth
 
Mar 5, 2020
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Could still be difficult to get sufficient motivation - 1 in 10,000 year impacts make good odds for NOT being hit any time soon;
Thanks to the secret science funded by the generous contributions of John D. Rockefeller to the University of Chicago the secret monopolization of geochronology would have never have been possible.

John D. Rockefeller was an oil man. Interstellar asteroid impacts create the geologic conditions for oil. Geochronology is bought and paid for science. Thanks to Rockefeller and the oil companies’, interstellar asteroid impacts are completely missing from the published scientific and geological literature.

Multiple impacts in or near North and South America resulted in the extinction of the Megafauna on both continents. All published information about the dates is suspect but it could be around the Younger Dryas.

The impacts which created the Eastern Mediterranean sapropels. What is the actual date for the S-1 sapropel because you should automatically assume that the published date is a contrived fiction.

The Late Bronze Age Collapse appears to be the direct result of an impact. Some of the first archaeologists sent to investigate the Late Bronze Age Collapse were from the University of Chicago.

Impacts happen a lot. But this information was more valuable as an economic secret than as publicly available science.
 

aff

Mar 2, 2021
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I think that they do build big parts here on terra firma 🌏 but they also have to send up the connecting parts too.
 

Catastrophe

There never was a good war, or a bad peace
Feb 18, 2020
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If the weight is not an issue, why not build the whole station on the ground and lift it in one go.

Since this is not the plan, there must be something against it, nicht wahr?

Cat :)
 
Mar 11, 2021
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Before having a clear understanding of the solar system, it is recommended not to excessively plunder or colonize the space domain.
If the solar system itself is indeed a "living body", we are undoubtedly the "cancer cells" in his body. Now that the earth is overwhelmed, the migration to space may represent the proliferation of cancer cells.
 
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