Never Exploit Venus & Mercury: A Pity for the Solar System

[Jon Richfield]

Venus and Mercury arguably are the most valuable real estate in the Solar system. I propose a reason why we will never exploit them, and why it is a pity. See next message.

 

[Jon Richfield]

Venus for Termites



or Whatever Happened to Hubris?



Ever since Babel, probably as an after-effect, Mankind has been unable to unite to meet large challenges. The nearest thing to a counter-example in recent history was the Ijsselmeer dam; the Dutch practically pawned their country for it, but that was just one nation. As a species we lack the long view, the guts, the commitment, for projects which politicians in power will not live to profit by. We are monkeys rather than termites, and none the better for it. Consider a project tailor-made for a termite civilisation on our scale, the conquest of Venus. At a stroke it would more than double the land space available to humanity, render the species practically immune from asteroidal wipe-out or cosmic catastrophe for five billion years or so, increase industrial capacity several-fold, and create the infrastructure to establish a race of spacefarers who could conquer this corner of the galaxy.



As apes however, we stand a better chance of growing ourselves termites’ wings.



And that is a pity. Apart from a shortage of hydrogen, Venus is good real estate. Its atmosphere is largely vaporised rock (CO2) and its climate is a bit dodgy, but all that depends on a single problem: the Venusian day. Adjust the day length and hey... well not presto, but certainly abracadabra, we double our current living space and gain an equal area for industrial real estate into the bargain. We also get so much free, renewable energy that to burn either molecules or atoms for large scale power would be ludicrous in the next few hundred million years, on Venus at least.



The trick is to adjust Venus’ sidereal day to equal the length of its year, so that it permanently keeps one face to the sun. In the process we would also strip local space of all threatening asteroids. We would hunt down everything movable, all the way to the Kuiper belt, and drop it with precise aim on the appropriate limb of Venus. Since she has a retrograde spin, we would *speed up* the rotation.



By exploiting the potential energy of rocks in remote orbit, we could profit energetically by a factor of a hundred or so; more if we handle the slingshotting neatly. We would invest in steering the missiles rather than impelling them. Some 70000-80000 10km rocks should do the job nicely -- a total mass about equivalent to the top few kilometres of Texas. Would-be comets (“dirty snowballs“), would be even more rewarding, because of their hydrogen content.



It might take a millennium or two, but that is a pretty modest price for five billion years worth of planet, surely?



Once Venus settles into its new role as the only planet with six poles (perihelion (or solar) and aphelion (or antisolar) as well as North and South, East and West, not to mention NNW!) and three equators to match, the current east-west equatorial wind will decay into turbulent convection and the weather forecast for the antisolar pole will be: frigid sulphuric rain, followed by blizzards with precipitation of about two kilometres of dry ice. The remaining atmosphere will be mainly nitrogen and some oxygen at roughly earth’s atmospheric pressure.



It seems *meant*, doesn’t it?



Around the "solar" twilight equator, convection should establish a permanent steady wind of enormous power. If ever there was a dream environment for a wind farm...! Since the wind speed would be fairly constant, we could design windmills of great efficiency for a modest price. For the price of installation and maintenance of generators, it should supply electricity for the entire residential region: the cooler half of the dayside, nearest the twilight equator.



At the industrial areas at the Solar high latitudes, we would exploit solar power of an intensity to make the best on Earth look feeble, not to mention intermittent and seasonal! The dayside would exceed twice the usable land area of Earth.



It’s not what you have, it’s what you do with it!



For a few millennia we would live indoors, but seeding of temperate zones with algae, plus employing spare solar power to split CO2 should improve the atmosphere till it becomes breathable for humans. Water would be the main problem. Venus remember, is poor in hydrogen and water would settle out on the night side. Coal mining on Earth might find an analogy in ice mining on Venus. But fine tuning the planet’s rotational obliquity and day length would be a continuing concern, so to make a virtue of a necessity, private enterprise Rockrat astronauts would always be hunting ammonia- and water-rich comets to drop with great precision on the night side. At least Venus would be one planet where water is properly valued!



Still, we need not be obsessively pessimistic about water. Pile up dry ice to about two kilometres depth, and you may expect a significant glacial flow. The night side cap of CO2 would continuously flow towards the twilight zone and carry vast amounts of scoured rock, moraine which might, or might not be valuable in itself. As the CO2 reaches warmer areas, it volatilises and for the most part, it would quickly freeze out again on the night side. However, some of the first volatiles to settle out of the atmosphere would be the water, ammonia and sulphur oxides. They would remain behind as harvestable powders in the moraines. They might be only a percent or two of the original atmosphere, but that would amount to a lot of valuable material. What is more, such valuable volatiles would continuously snow out on the night side, but they would all do so near the edge. They would soon be borne out to where they could be collected and recycled. In fact, in the process they would be fractionated and could be purified cheaply.



The whole process is so inviting that it makes a mockery of the idea of terraforming Mars. For probably no greater investment, and in my isolated opinion in no greater time span, we would get far more planet, develop far more valuable technology, and earn a far, far more valuable, power-rich prize.



If we were termites.



But sadly, being monkeys, not termites, we never will do it...

Monkey Jon

 

[Danger]

I have neither the energy nor the sobriety to read that whole post right now, but the first few paragraphs had me rolling.

 

[Jon Richfield]

I have neither the energy nor the sobriety to read that whole post right now, but the first few paragraphs had me rolling.

Much thanks! I'll wait with bated breath for the hangover!

 

[Danger]

Alas... I don't get hangovers. If I did, it would probably be a lot easier to quit drinking.
Congrats, also, for being the first person that I've seen spell "bated" properly. (It's usually "baited". )

 

[Jon Richfield]

Alas... I don't get hangovers. If I did, it would probably be a lot easier to quit drinking.
Congrats, also, for being the first person that I've seen spell "bated" properly. (It's usually "baited". )

Now Danger, don't you bait me into a tirade on spelling, literacy, and all that!
Punctilious spelling is addictive. It should come with a government health warning.
Go well,
Jon

 

[jselin]

Jon,

As I started to read your post I was already writing you off but I continued and I must say I'm impressed. As crazy as the idea sounds I admire you for thinking outside the box and thinking through so much of the detail. As far as mega projects go its not just about coming together but the true cost of implementation. As a species we are only just becoming capable of anything really and we already have our eyes on lofty goals. We will need to implement serious time and labor savings to attempt anything at even 1/1000th the scope of this... something like near automated design and manufacturing in a complete multiphysics simulator to make implementation a much smaller line item on the overall budget and to allow for high certainty pricing of implementation with high certainty of success.

Right now its like we're on food stamps and talking about buying a yacht :)

 

[Ranger Mike]

Danger
its 5 O'clock some where ..i just got to find out where!

 

[pallidin]

You know, there are certain recreational drugs that can cause this type of rambling.

 

[Jon Richfield]

As I started to read your post I was already writing you off but I continued and I must say I'm impressed. As crazy as the idea sounds I admire you for thinking outside the box and thinking through so much of the detail. As far as mega projects go its not just about coming together but the true cost of implementation.

JS, thank you for a response that left me feeling very complimented.

As a species we are only just becoming capable of anything really and we already have our eyes on lofty goals. We will need to implement serious time and labor savings to attempt anything at even 1/1000th the scope of this... something like near automated design and manufacturing in a complete multiphysics simulator to make implementation a much smaller line item on the overall budget and to allow for high certainty pricing of implementation with high certainty of success.

I agree with everything you have said in your posting. I have had some thoughts along the lines that you mention in the foregoing paragraph. I wonder whether I should post those thoughts. If I do, then maybe I should put them into another thread. I'll think about that...

Right now its like we're on food stamps and talking about buying a yacht :)

You got that right! Don't think that I underestimate the scope of the project. It actually is so large that although I speak glibly of the rewards being measured in terms of gaining another planet, it is not clear that there would be profits that make sense in terms of current economic concepts. For one thing, we are speaking about a project that would take at least several centuries even to adjust the planet's rotation satisfactorily; and probably 1000 years or thereabouts to make serious progress with the (I hesitate to call it "terraforming", because the results would be so different from Earth) ground-level engineering.
I argue that the sheer scope of the profits (a whole new planet...) is several orders of magnitude beyond the costs, and this certainly is true. However, how do we go about defining the economics of a project that will show no profit during the lifetimes of our great great great great great great grandchildren?
Even if we get our act together and extend the human mind and longevity to scales are rational for a social species whose major intellectual, psychological, and experiential capital is in the minds of its individuals. As things stand, our functional lives our ridiculously short for any of our conscious objectives. Unless we overcome that, our only possible purpose as a species could resemble some meta-purpose, or meta-consciousness, such as Aunt Hillary in "Goedel, Escher, Bach" by Hofstadter.
A social insect (such as indeed, a termite) might have no difficulty with that question, but a human?
Now, as you have, I am sure, fully realized, this is a fun idea for me. I have no intention of running out, breaking through the cordon of bodyguards, and buttonholing some of the current superpower presidents to move them to start a super-Manhattan Project to conquer Venus and Mercury (Mercury is a honey! But I think I will let that proposal simmer on the backburner for now. Still, I hope you can see the rationality of the insight that the inner planets are where our short-term future prospects lie.)
At the same time, beyond the fun, I cannot escape a chill feeling that if we do not break into the point of view, the hubris, that would permit humanity to tackle such projects, we are doomed. Doomed in this century? Probably not. Doomed in this millennium? Very likely not, if certain trends can be managed. But doomed certainly. A single planet, even without having to deal with our destructive tendencies as a species, is a sterile bottle. We break out or perish in our own midden.
But, for a somewhat warmer feeling, maybe I should start a few related threads. Thanks for the encouragement so far.
Cheers,
Jon

 

[pallidin]

For one thing, we are speaking about a project that would take at least several centuries even to adjust the planet's rotation satisfactorily;

OK, now, this is ridiculous.

 

[Jon Richfield]

Right now its like we're on food stamps and talking about buying a yacht

Oh yes, and I forgot to mention that the Ijsselmeer dam is in some ways a very illuminating model. It is a fascinating subject and I commend it to your attention in case you do not happen to know much about it. Wikipedia is a good place to start.
Now, the point I am getting at is not so much that the project is big, but that because it is big its actual objectives have changed during its history. They bid fair to change again, if not actually continually. Such change is not the kind of thing that one naïvely associates with engineering projects, but on such scales and larger, I reckon that we very much do need to think in such terms.
In nature there are many models for such indirect or unforeseen changes in the direction and context of development.
Beware! As a line of thought, this one is fit to swallow minds.
Cheers,
Jon

 

[Jon Richfield]

OK, now, this is ridiculous.

Very likely, but could you please elaborate a bit? Are you referring to the time scale, the project, the objectives, the economics, the engineering, the...
Come on, if you bothered to reply, you could say a bit more than that surely?
Thanks in anticipation,
Jon

 

[pallidin]

Jon, chill.
Your theory and thrust has no substance of "doable" applicability.

 

[Jon Richfield]

You know, there are certain recreational drugs that can cause this type of rambling.

I didn't actually, though I'll take your word for it. But are you talking about the Venus thing or the hangovers etc?

 

[pallidin]

Jon, we can not just adjust the Earth's rotation with some sense of specificity:
This is not possible with current technology at all. The forces demanded are far greater than we could produce. Even with nuclear devices.
Our Earth is very massive.
Not to mention the fact that, if we could do that, it would be extremely dangerous to alter what we have now.

 

[Jon Richfield]

Your theory and thrust has no substance of "doable" applicability.

Why not? It might be a large project by current standards, but so was the Ijsselmeer project in its day. The technology is a modest, quantifiable extrapolation of what we know, and much of what we would need to do in preparation would have thoroughly doable and material benefit even if we changed our minds halfway.

So far you have not said anything beyond denial. It is not as though I were suggesting the colonisation of Mars or a universal Zodiocracy, is it? As an engineering project it is rational in terms of resources, mechanisms and rewards. What more is necessary, beyond commitment?

Let's hear something substantial; I am not in a snit. I am dead serious. I really do want some remarks. Have you identified a single obstacle, let alone anything that comes anywhere near rivalling what I see as the real killer: the Termite/Monkey dichotomy? Or the (closely related) problem of long-term projects in our current ideas of economy?

The fact of the matter is that we are doomed, but the reason we are doomed is nit that we couldn't do it but that, being monkeys, we won't.
Cheers,
Jon

 

[pallidin]

I am going to retire for the evening/morning and allow you to reflect on those thoughts.
Nite, nite...

 

[Jon Richfield]

Jon, we can not just adjust the Earth's rotation with some sense of specificity:
This is not possible with current technology at all. The forces demanded are far greater than we could produce. Even with nuclear devices.
Our Earth is very massive.
Not to mention the fact that, if we could do that, it would be extremely dangerous to alter what we have now.

Pallidin,
Thank you for coming back, but are we talking about the same thing? You said that we cannot adjust the Earth's rotation, and with minor reservations, I agree. As for the use of nuclear devices for any such purpose, that really would be ridiculous! For one thing, I doubt that all the nuclear devices we could scrape together would suffice. But how did the adjustment of the rotation of Earth get into this? I never mentioned that, and if anyone has any ideas as to why we should want to do this, do let me know please, I am absolutely stumped!
What I proposed was to change the rotation of Venus, and I explained both why and how. You will notice that in comparison to any plausible adjustment to the Earth's rotation, the problems would be trivial.
Thanks again,
Jon

 

[pallidin]

What I proposed was to change the rotation of Venus...

Uh, what?! Your kidding, right?

No offense intended, but that is simply beyond ridiculous. The energy required is mind-numbling enormous.

 

[Jon Richfield]

Uh, what?! Your kidding, right?

Errr... no. Not last time I checked. Should I be?

No offense intended, but that is simply beyond ridiculous. The energy required is mind-numbling enormous.

Well Pallidin, no offence on this side either, but did you actually read the proposal? The energy is there for the taking. It would take a certain amount of patience, good sense and investment, much as one needs a match or flint and steel, or perhaps a lens, to start a forest fire, but the energy is in the air and the organic material, abstracted from the sun. It is no good arguing that a match is all we have and it has mind-numblingly, enormously, less energy than a forest fire, therefore we cannot start a forest fire! (I admit that as a biologist I find the forest-fire analogy nauseating, but you understand what I mean, I hope!)

I remind you of what I propose: In the near Kuiper belt we have enough accumulated kinetic energy to drive the whole planet of Venus into the sun if we chose. I do not propose anything so drastic. Gently, gently say I! Just a slight rotational adjustment...

You thought at first I was talking about Earth's rotation, right? Now, THAT would be expensive! For Venus, all we need is to speed up its rotation by about 8%; for Earth we would need to slow its rotation down by a factor of about 365, even if we could imagine a reason for doing so, which I for one, can not! Are we talking about the same thing?

I am proposing something with certain classes of objective rewards, and proposing how to do it with existing resources.

Where I come from, that is called engineering. It certainly is only the first phase of engineering, the conceptualising stage, but it is not fantasy. The obstacles are political, not technical.

In turn, so far all you have said is in effect: "No, it is too big!"

Please explain the merit of your assessment.

Cheers,

Jon

 

[jselin]

A recent article on Physorg about a newly discovered planet brought this discussion to mind!

http://www.physorg.com/news204999128.html

Tidally locked Earth like planet! This place would have all of these extreme conditions. The article even describes the potential habitable zone in the same way.

 

[Jon Richfield]

A recent article on Physorg about a newly discovered planet brought this discussion to mind!

http://www.physorg.com/news204999128.html

Tidally locked Earth like planet! This place would have all of these extreme conditions. The article even describes the potential habitable zone in the same way.

Hi J,

Many thanks for the reference. It is interesting from many points of view, isn't it? For one thing there is the red dwarf aspect. I have updated the Wikipedia red dwarf Article in the light of that information. In some respects the red dwarf implications would be more optimistic than those for Venus, whereas in others they might well be less. Similarly, the fact that Gliese 581 g is more massive than Earth entails certain grounds for optimism, whereas conversely the lower the gravity of Venus is attractive in other respects.
The habitable zone of Gliese 581 g not only suggests enormous scope for certain forms of evolution, but for far greater implications than anything suggested in the Wikipedia article, including the paragraphs I added. In the light of our palaeontological history on earth, the scope for speculation on Gliese 581 g beggars the mind!

Speaking of other planets, I must get onto the subject of colonising Mercury, mustn't I? It seems to me a likely place for a far more healthy existence than Venus. As they say, in the real estate industry it is all about location, location, location...

Cheers,

Jon

 

[Algr]

I can't imagine a society that could summon the energy to alter the rotation of venus would have much use for windmills and solar panels. Building an all new planet would be easier, faster, and more certain of success then what you suggest.

And the Monkeys vrs termites thing is just insulting. Termites are fixed in their behavior and could never build anything that they haven't done a million times before.

 

[Jon Richfield]

I can't imagine a society that could summon the energy to alter the rotation of venus would have much use for windmills and solar panels. Building an all new planet would be easier, faster, and more certain of success then what you suggest.

It is hard to tell how serious you are. It is even harder to tell whether to hope that you are...

Let us consider a few of your putative pleasantries:
I propose using mainly available sources of kinetic energy to alter the rotation of a planet by a few percent so that the natural consequences can do most of the terraforming, and you...

Let's get this straight. You reckon that: Building ...? an ...? all ...? new ...? planet ...? would be easier, faster... etc?

Well, that sounds like a really tempting assessment Algr! This I cannot resist! Do please demonstrate your seasoned expertise in quantity surveying for such matters! Tell how you would go about it, where you would get your material from, how much of it is available, and how you would obtain it and move it, and how you see all that as being cheaper and easier etc.

Give him room folks! This will be a tour de force to knock Blondin right off his high wire.

Gosh! After that the rest seems almost anticlimactic. A few lines of that special arithmetic of yours should take care of it. Here we have a people who have carefully bombarded a planet with enough Kuiper Belt objects to use the potential and kinetic energy to perform a trifling adjustment to its rotation, and having done that they no longer need prime sources of energy? Suddenly the laws of thermodynamics are repealed? Free solar energy in horrendous amounts, in convenient forms such as stable convection cells and high intensity sunlight, exceeding anything we are burning on Earth, and practically pollution-free, and suddenly they no longer need it?

You absolutely gotta be joking!

And the Monkeys vrs termites thing is just insulting. Termites are fixed in their behavior and could never build anything that they haven't done a million times before.

You seem to be easily insulted Algr, as well as being hard to please. I can think of just one species of primate that has achieved greater feats of engineering than termites (and it is arguable to what extent those feats are greater in proportion) and you are dissatisfied with the compliment of the comparison? And at the rate that species is going it might well not last for more than a few centuries, after a distinct history of less than a hundred thousand years and a generic history of less than five million years.

Now you want to compare that scruffy band of scrabbling rabble favourably to an order that has been doing very nicely thank you, for some three hundred and fifty million years? An order that has seen the dinosaurs, pelycosaurs, therapsids, and the tertiary giant mammals come and go?

You may not have much sense of proportion man, but you sure got style! So termites have fixed behaviour have they? On what time scale? And from what perspective? I won't ask you just how rigid their behaviour is, or why that should matter, because I feel a bit guilty at throwing you a chunk of homework that I would be surprised to see you complete, but why don't you go and read up about Ant Hillary? And when you have done that, ask yourself how she stacks up against the neurones of your own central nervous system.

You also might want to find out how many things termites are building today that they never seemed any likelier to do in their early days, than cockroaches today would be likely to build six-metre mounds.

Then again, explain why future termites a few million years down the line must necessarily be no more intelligent than today's species than you are (I hope!) more intelligent than your own ancestors of the Eocene? (Heck! Make that the Miocene!)

What is more, try reading what I wrote in a sensible perspective. Just what did you think the termite/primate analogy referred to? No one else seemed to have trouble with it, and yet you seem to think yourself intelligent enough to take offence? Offensively?

I don't know what you have been smoking, but I bet it has the govt health warning aaallll over it!

 

[JaredJames]

You're proposing changing the rotation of a planet. Altering it's angling momentum. That is enough to write you off in my books.

Sorry to be so blunt but you seem to be missing one key fact. We don't have the ability to pilot asteroids in a basic sense, let alone navigate them successfully into a slingshot of venus... 80,000 times!

It's all very well saying "if we do X we get Y out of it", but if we can't do X, we don't stand a change of achieving Y.

If we have the ability to do everything you describe with the asteroids (and in turn Venus), why would we be interested in Venus? We could simply build some big *** space stations, park them close enough to the sun so we get maximum solar efficiency from some solar panels and plant growth etc and then live on them.

 

[Algr]

Building a planet is simple. Instead of bombarding the asteroids into venus, we melt them together into a ring and spin it to produce centrifugal gravity. A dome over the inside of the ring holds in an atmosphere from small captured comets. This could be done from small metallic asteroids, that would cumulatively weigh less then a single one of the 70000-80000 10km rocks that you propose moving.

Small versions of this can be built today, and as we gain experience and technology we can build ever larger ones. Cumulatively, you'd have a planet sized living space long before anyone could set foot on venus.

 

[Jon Richfield]

Building a planet is simple. Instead of bombarding the asteroids into venus, we melt them together into a ring and spin it to produce centrifugal gravity. A dome over the inside of the ring holds in an atmosphere from small captured comets. This could be done from small metallic asteroids, that would cumulatively weigh less then a single one of the 70000-80000 10km rocks that you propose moving.

Small versions of this can be built today, and as we gain experience and technology we can build ever larger ones. Cumulatively, you'd have a planet sized living space long before anyone could set foot on venus.

Al, MEGO!

Apart from a few minor details like security (I can just imagine the resilience of a rock ring with a magically created "dome", compared to a planet with an atmosphere!) simply getting it to work at all would require magic. Have you worked out what would happen to your ring's dynamics? Even a static ring would take some building; moving things around inside the ring would risk having resonances that would make life positively interesting.

You also seem to have a cheerful attitude to timescales and dynamics. Just how do you intend to melt your (say 100000; use the same figure for my scheme; who cares, as long as we can ease the strain on our calculators!) rocks? Say "Let there be heat"? How many joules of heat would you say would melt something like 1e17 tonnes of rock and metal? Do you suppose that the entire stockpile of nuclear weapons on Earth would suffice? (Don't ask me, I haven't worked it out yet!)

Al, I really must apologise for the note of unintentional asperity in my previous note. I must hand it to you. You may not have arithmetic, but man, you got style!

Nor does it stop there! How do you want to fetch your rocks? In a satchel? In the Venus scheme we would encourage them to fall (which certainly will require energy for steering, but will pay it back with about 10000% interest) and where they land, they yield up what they brought, both matter and energy. Bang!

Right?

But you? You simply collect them the same way (or have you developed teleportation while I wasn't looking?) and when they arrive at your growing ring of raw rock and meteoric iron and iridium, you errrrr... stop them somehow? Am I missing something? Sure as shooting Al, someone is missing something!

And melting your rock isn't challenging enough, is it? Oh no! You want to convert the unrefined rock and metal into structural material such as will make some unspecified ring to live in and on, and cover it with a dome? Transparent, no doubt? Next time you have ten minutes and a blowtorch to spare, do a bit of rock melting and let me now what colour and strength of dome you expect to get from meteoric rock. Or do you expect to refine meteorite-proof silica slabs somehow in free fall? Ask the guys in Spacelab how easy it will be, will you?

You speak of cumulatively trivial masses of material, but don't you realize that cumulatively trivial masses are trivial resources as well? Otherwise why are we still grubbing around on our nasty bit of massive rock with its deeply buried treasures of precious metals at its core? Why not just pack ourselves a few pup tents and establish ourselves in orbit?

But Al, you are trying to have your cake and eat it too, aren't you? Like: "Cumulatively, you'd have a planet sized living space long before anyone could set foot on venus." Less than one of our 1e12 tonne rocks would suffice for a "planet"?

Tell you what Al, you give us an outline design, nothing tediously detailed, just enough for us to get some idea of the orders of magnitude of the "planet" you would build out of your 1e12 tonnes, assuming that the whole "rock" is usable material. You could hardly ask for a more generous offer than that, could you?

And as a special favour, if you come up with a halfway decent scheme, I'll tell you how to Terraform Mercury even more rewardingly.

You see Al, small may be elegant, but for some things small is just mingy!

Sorry, got to go.

Cheers,

Jon

 

[Jon Richfield]

You're proposing changing the rotation of a planet. Altering it's angling momentum. That is enough to write you off in my books.

JJ, no one said a blind word about angling, not for minnows, moonfish or Moby Dick. You might just be thinking of angular momentum, but if you take a look at the proposal, you will see that angular momentum is strictly conserved. When I came up with this I expected all sorts of flak of course, but I didn't think I'd have to put up with folks who not only didn't understand angular momentum, but confused it with fishing. <siiiigh!>

Sorry to be so blunt but you seem to be missing one key fact. We don't have the ability to pilot asteroids in a basic sense, let alone navigate them successfully into a slingshot of venus... 80,000 times!

JJ, don't be sorry, be sensible. Of course we have the ability. Here is a homework assignment for you. Go and work out a few details for a system to do so, and come back when you can describe it and compare notes with my proposals. And when you can explain why there is in fact conservation of angling (Good Grief! I suppose you have a non-standard keyboard, huh?) momentum.

If we have the ability to do everything you describe with the asteroids (and in turn Venus), why would we be interested in Venus? We could simply build some big *** space stations, park them close enough to the sun so we get maximum solar efficiency from some solar panels and plant growth etc and then live on them.

Parking next to the sun is another subject. It does not greatly affect this project, though the Mercury project is far superior to that rather stale idea. If you want to live on a hot rock, sell the idea to Alr; he has the idea that anyone who could undertake such schemes would have no use for solar or wind power. He not only doesn't believe in conserving angular momentum, but energy in general, I would expect. But he does share your contempt for material resources it seems, judging from his domed ring "planet".

By all means come back for more details when you get stuck, but now, as I said to Al, must run.

Jon

 

[JaredJames]

Im on my phone so it was auto text trying to tell me what i wanted to say.

You want to alter the rotation of the planet, aka change its angular momentum. Where it goes / comes from is irrelevant. Changing it isn't as easy as you are making out.

Are you seriously telling me you know a way to pilot an asteroid, 10km in diameter, into a slingshot around venus, let alone consistently 80000 times?
It isn't down to me to come up with ways for your plan to work, you want to claim it can be done, you tell us how.

How about you cite a source for piloting asteroids or changing the angular momentum of a planet as per pf guidelines?

 

[Algr]

Mr Richfield, If you want people to take your ideas seriously you need to learn to have some respect for your audience. First the termites and monkeys, then you devote a whole paragraph to a typo that anyone ought to see means "angular momentum".

It should be obvious that my "planet" is simply a series of space stations. We've already built space stations, so arguing that they aren't feasible makes you look a bit silly. Mining asteroids for materials is not something I invented, and as for energy, how about focusing sunlight? (No we don't need the whole station molten at once. Sheesh.)

As to your plan: The moon reaches 200 degrees on it's day side. A tidally locked venus will have habitable temperatures only on a narrow twilight ring. And what will happen to geology when ground that has been at 800+ degrees for millions of years starts to cool down and contract? (Especially on the night side?) What will those earthquakes be like?

And finally there is your timescale. In 1000 years if we aren't extinct, we will have manned missions to many other solar systems. Is it likely that we won't find anything better to start with then venus? It is pointless to make plans with no payoff for a millennium when humanity changes as fast as it does.

 

[Jon Richfield]

Im on my phone so it was auto text trying to tell me what i wanted to say.

Ah! Well that is a relief. I had been wondering at what level to pitch the response. I seldom use a cellphone and avoid auto for exactly that sort of reason, so that explanation had not occurred to me. It did not look like finger trouble, so I got the impression of scientific illiteracy and I thought I was in real trouble. Welcome back to the world! At least we now can talk sense at each other.

You want to alter the rotation of the planet, aka change its angular momentum. Where it goes / comes from is irrelevant. Changing it isn't as easy as you are making out.

Where it goes to or comes from is extremely relevant. It is crucially relevant. Even your cellphone could tell you that if you spin it. If I had proposed that we correct the planet's spin by getting a lot of marathon runners to accelerate on the equator, then you might have a point. After all, we would lose the adjustment to the angular momentum every time one of them stopped for a rest. If instead I had a lot of really humungous flywheels accelerating near the poles, you might be at a slightly smaller advantage, because I could have the flywheels spinning in a vacuum on magnetic bearings. I might even tune them to achieve permanent changes to their system's angular momentum by electromagnetic interaction with the ambient magnetic field of the solar system. But I think you will accept that option is unattractive in engineering terms, so I would not push it too hard if I were you; always aim for practicality, I say, and you see JJ, those flywheels would have to be really huge, the ambient field is very weak, and above all, every joule equivalent of the planetary angular momentum would have to be generated locally.

We could not afford that JJ, so where we are to get it from is indeed relevant in the highest degree.

You see?

OTOH, changing the angular momentum is as easy as I make out. It is exactly, precisely as easy. No more, no less. Work it out. Any mass at a given (linear) momentum striking the planet on a given trajectory will affect its angular momentum by exactly that product of its mass and velocity in vector addition to the orientation of the planet's spin. One makes certain allowances for atmospheric and pedological factors of course, but what else is new?

Unless of course you know different! Do tell us if so!

Are you seriously telling me you know a way to pilot an asteroid, 10km in diameter, into a slingshot around venus, let alone consistently 80000 times?

Well, actually I wouldn't insist on the 80000 figure, because I have a sneaking suspicion that the Kuiper belt is not set up for our convenience as an array of conveniently standardised 1e12.5 tonne blocks, so let's work on a basis of 100000 times. 80000 is such an awkward number, isn't it?
But BTAIM, no, although I could do that (in principle) it would be pointless most times, wouldn't it? For a start it would not affect the planet's angular momentum, would it?
No, the idea would be to strike the appropriate limb of the planet solidly. Would you settle for that? That would affect the planet's angular momentum, right?

It isn't down to me to come up with ways for your plan to work, you want to claim it can be done, you tell us how.

JJ, I already have someone coming down on me for not being nice enough to you. I don't need you to tell me of at least one way in which it can be done, but for me to tell you would really smack of excessive patronism, don't you think? Besides, who knows, with your skills maybe you could propose something really different and original (my approach is creakingly pedestrian, I am sorry to say!) So let's leave it at that for now. When you find yourself stumped, let me know and I will help you out of your difficulty and explain some of the hazards of trying to assert and support a negative.

How about you cite a source for piloting asteroids or changing the angular momentum of a planet as per pf guidelines?

Ah yes! Silly me! I had not read on far enough when I keyed in the previous paragraph. Oh well, to help you on your way, any school physics textbook this side of the antidarwinistic bible belt should give you ample material on angular momentum and momentum vector arithmetic. Let me know when you get stuck, but please organise your questions first. Firstly, that way you will find yourself able to answer many of them yourself, and far more profitably than having me do it for you. Secondly, I don't have the time for too much stuff that your teachers should have told you already.
It might however, speed you on your way if I suggested that steering any solid body in space follows the same general rules, and that some of us have managed pretty well already.
Yes?
Go well!
Jon

 

[Jon Richfield]

Mr Richfield, If you want people to take your ideas seriously you need to learn to have some respect for your audience. First the termites and monkeys...

Mr Algr, Thank you condignly for your concern and correction. I find myself however at something of a loss to excogitate the significance of your apparently resentful preoccupation with primates and termites. Would you please explain whether and how you read anything offensive into that analogy; and in fact whether you understood the parallel at all? I hardly expected to have to spell out anything of that kind in this forum! As a helpful hint, avoid invoking stereotyped behaviour; it patently is not your field of expertise.

...then you devote a whole paragraph to a typo that anyone ought to see means "angular momentum".

A typo...? Al, you leave me breathless. Not only could anyone see what it meant (assuming that they knew what angular momentum was, which btw, most people don't, even including some in this forum!) but I did too. I even helpfully supplied the correction, remember? Free of charge! What is more, as typos go, it was rather misleading. If it had been "agnular" or "angilar" or "angulr" or "anngular" I would have passed it by as I do with all the usual stuff. You don't perpetrate anything of the kind of course, but I certainly do, or worse. You might find it instructive and even entertaining to read Laurence Durrell's "Frying the Flag".

So AL, try it from my perspective: JJ writes a rather curious argument suggestive of difficulty with the arcane concept of conservation of angular momentum, and spells it so hopelessly wrongly as to suggest that he had never seen the word. From this I am to deduce that he does indeed know what he is talking about and that he was betrayed by his cellphone?

Well, he took it in good part and pointed out that the error was indeed trivial and understandable, so that was that. We sorted it out in one exchange. But what your role in this might be, I am not so sure.

It should be obvious that my "planet" is simply a series of space stations. We've already built space stations, so arguing that they aren't feasible makes you look a bit silly.

It should indeed be obvious. It was so obvious to me that I could not understand why you were having difficulty with the concept. Silly, silly me, as you point out, if only I had in fact said that no such thing as a space station were feasible. Which please note, I had not. (Mind you, I would hesitate to point to our only extant specimen of a space station as a counterexample )

But Al, it is simplistic to classify a planet as a space station or a space station as a planet, as if the two were in general interchangeable, simply because they share certain orbital characteristics. You might well find it to be a wholesomely sobering exercise to sit down for a few hours and draw up a list of the respective attractions and functions of orbiting bodies of different orders of magnitude. Start with say something tiny, perhaps a few dozen times the scale of the Space Station. Then try something a few km across, say something like Phobos. Then something like Ceres. Then Mercury. (Good one Mercury!) then Venus (Great one Venus! For termites anyway!) Gas giants? Hmmmm... Well think about them anyway. Good stuff thinking. Pity it hurts so, isn't it? Worse than gym time!

If you do your assignment properly, you should be astonished at some of the implications and prerequisites that emerge.

Mining asteroids for materials is not something I invented, and as for energy, how about focusing sunlight? (No we don't need the whole station molten at once. Sheesh.)

You never invented mining asteroids for materials? I thought everyone had done that at one time or another. Oh well. But you know, you really need to do better than that if you want to stop confusing issues, which is a great waste of energy and intellect. If we want to mine asteroids, we can do that a lot more cheaply than moving them into new orbits and melting them and forming them into rings and attaching domes and all that. All we need do is go to where they already are, assess their value, and send out some automated mining equipment to retrieve whatever we happen to want, and leave the unwanted bits where we found them. If we discover that say, Themis is 50% osmiridium, such a project might be worth while, but anything much less dramatic than that is not likely to be attractive, certainly not in comparison to what we could do on a planet of our own, such as Venus. (Notice that moving Themis into a more convenient orbit so that the application of solar heat would become attractive, would be a project that would dwarf the challenge of adjusting the rotation of Venus.)

Now, just what do you expect to mine from your "planet" once you have assembled it and melted it and all that Good Stuff? All several trillion tonnes of it? How do you expect to make a viable proposition of it? What would Earth profit, and what would that artificial space station present as a self-supporting environment to long-term occupants? Mining? Agriculture? Fabrication? Energy? Fundamental research? Population space? All of those perhaps, but I really would like to see you spell it out cogently. Please! Something better, and with a better rationale than piecemeal solar energy fusion of asteroidal or meteoritic rock! OK?

Eish...!

As to your plan: The moon reaches 200 degrees on it's day side. A tidally locked venus will have habitable temperatures only on a narrow twilight ring. And what will happen to geology when ground that has been at 800+ degrees for millions of years starts to cool down and contract? (Especially on the night side?) What will those earthquakes be like?

Uh... I don't suppose you mean Kelvin? Rømer? Celsius? No? Then I suppose you mean Fahrenheit. Right? Tsk tsk... Oh well.

Al, did you notice that the primary rationale of the scheme depended on first giving Venus an atmosphere roughly comparable to that of Earth? Did you really think that this would have no effect on the surface temperature? Please justify your assertion, if so. If not, what would you expect to happen to the temperature on various parts of the surface of Venus?

Only a narrow twilight ring you say? Forgive my pointing out that you have a facile way of using qualitative terms to assert quantitative propositions. Note that firstly, if that ring of living space were only a few km wide, it would dwarf anything that you could assemble in space. If it were just 250km wide (very narrow, right?) it would be about 10000000 square km. Secondly, solar intensity at the orbit of Venus is only about twice that on Earth, and the angle of the sun to the horizon would be of great relevance, so actually, about the outer half of dayside, the face of the planet facing the sun, should be very livable; even the inner bullseye with the sun at its zenith would be perfectly liveable with a bit of shading and solar power. It would be a fabulous region for industrial real estate. After all this is Venus we are discussing, not Mercury ! Also please note that dayside is about double the land area of Earth.

Oh yes, the earthquakes... well quakes anyway. Frankly, I am unthrilled. There might well be quakes, but I suspect that our 100000 dino-killer impacts would have shaken up most impending quakes for a start. Also, Venus seems to have very little in the line of tectonic activity. The rate of cooling by conduction from underground to the surface would be very modest indeed. Even the heat content of soil 100m subsurface would show very little change in 1000 years. The nightside glaciers would cause far more quake activity, but then who lives nightside anyway? If at the time we begin to move in and settle, we find that quakes are troublesome, we simply adapt our building techniques. I was tempted to invoke the super-science of our descendants that you and JJ set such store by, but most of the quakes, if they are caused by cooling, would be horizontal S and P waves; easy to build for even using our current primitive techniques, right?

And finally there is your timescale. In 1000 years if we aren't extinct, we will have manned missions to many other solar systems. Is it likely that we won't find anything better to start with then venus? It is pointless to make plans with no payoff for a millennium when humanity changes as fast as it does.

"If we aren't extinct..." well, since we are not termites that is a large assumption, I grant. I frequently am surprised by the fact we have made it as far this. But 1KY is such a vanishingly short period that if we can't survive it, we hardly matter.

But really Al... Other solar systems...

You know, I actually am all in favour of expeditions of various kinds to other solar systems, but there is no reason other than idealism even to contemplate them! 1KY? Suppose we consider a confirmed, suitable planet at 10 LY away (adjust my figures to suit your argument, but if you reckon on a nice, cosy 'ole at 1 LY away, I'll want to know where you get your data from!) That is about 1e14km, right? Suppose we can get a suitably sized colony ship up to an average speed of 1000 kps (tell me when you have worked out how to do that and how much fuel you would be taking along and what speed you would expect to achieve en route! Bussard jets? Tell me more! Lots more!)

That leaves us with a journey of a mere 1e11 seconds or about 1e3.5 years. OK? Never mind the preparation, the sales talk and politics etc, just the 1-way journey would take well over 3000 years. Not 1000, 3000!

Eh?? Who said "Round trip"? Over 6000Y? Not counting settling-in time?

Now, the Venus/Mercury/Asteroids schemes should offer at least certain advantages while they were under way, and huge rewards thereafter, but just how do you expect to get material (as opposed to ideological) rewards from your interstellar schemes? Trade? Emigration?

Sorry Al, but someone said something to the effect that if there is something you cannot do anything about, then it isn't a problem; it is reality.

It really is! There is a lot of reality to our corner of the universe.

Jon

 

[Algr]

This is the kind of discussion that can have no end, so I'm not going to bother...

 

[JaredJames]

This is the kind of discussion that can have no end, so I'm not going to bother...

Agreed. I think I'll give it one last shot and then I'll see if it's worth continuing.

Mr Richfield, you want to alter the angular momentum of a planet. Yes, your technique would work. I have never denied that, however you are failing to understand that getting to the point of changing the rotation is the problem. Piloting an asteroid into a slingshot around the planet isn't easy and so far you haven't proposed a way to do it multiple times. Unless you are willing to share how to accomplish that feat, it stands that we simply don't have that capability.

That is why I'm saying where it comes from / goes to is irrelevant. We can give all the ways we like to change the rotation of a planet (or do anything) but if we physically cannot achieve them (by means of flying asteroids around / into a planet or otherwise), they really are useless ideas to us until the technology becomes available. (And at the point it does, if we still want to use it for that purpose.)

Despite your lovely long response, you still haven't provided a way to actually send an asteroid from the belt to Venus. As above, any concept you provide after that is meaningless unless you can explain how we get over that massive hurdle.

There are no school physics books which discuss asteroid piloting. My argument isn't with your angular momentum issue. It is with getting to changing the angular momentum.

Despite the main point of my last post asking you to tell me how we get asteroids to Venus in the first place, you still haven't responded with regards to that.

At the moment it looks as if you've provided an idea and then expect everyone else to fill in the blanks as to how we achieve it. It's no different to me giving an idea regarding the use of a perpetual motion machine but not explaining how we get the PPM. I can go into great detail about how we use the device but constantly avoid describing how to achieve the device itself, expecting others to actually come up with the device for me. This is simply not how things work and a bad way of discussing a topic.

This is the last chance I'll give you to explain the following:
a) How we get asteroids from the belt to Venus.