Terraforming Venus

[SargeRho]

Machines can deal far more easily with vacuum than with 92 atmospheres and 500°C, basically for one simple reason. Mechanical Stress. The only mechanical stress a robotic miner operating in vacuum experiences is the friction of its own parts and the wear of the mining equipment.

On venus, you have tremendous heat and pressure to add to that. Machines operating in the deep ocean don't have much of a problem, because it's very cold. No need to put a cooling system in place to prevent the thing from melting. Due to the cold, you can even expose many things to the environment without trouble. That is not so on Venus, where you can't expose any parts that are heat-sensitive. Electric motors and electronics, to name a few.

Have you ever drilled a hole, in hard wood or stone? You'll then have noticed that the drill gets very very hot in the process. It cools down quickly, because the Atmosphere is by comparison very cold. Know what happens when a drill gets too hot? It bends and breaks. And that happens long before the 500°C mark. Now think of the stress that would impose on mining equipment on the surface of Venus. Things would have to be built out of extremely durable materials, which has the disadvantage of being expensive as hell.

Take Titanium. The main reason Titanium anythings are very expensive is not that Titanium is rare. It isn't, we use it as white paint. But Titanium is very hard, and takes special tools to machine. And I think it's kinda energy intensive to purify (read: separate from Oxygen, as Titanium Dioxide is the most common form).

If I was an investor and had to choose between Mars and Venus, I'd choose Mars, because it has fewer engineering challenges, and doesn't require equipment that is quite as expensive.

Sure, you can build drills made of Titanium Carbide or Tungsten Carbide, with Diamond tips and Titanium gears, as well as Liquid Helium cooling systems. But that would be extraordinarily expensive. You can use ordinary Earth mining equipment on Mars, with slight modifications. Same goes for Asteroids.

As for NSWRs, have you every looked at them, done any research? You're talking about storing highly radioactive fuel that will undergo fission if enough of it is concentrated. And the engine itself is basically a continuously ongoing nuclear explosion under water. Nobody has any idea how to build it, or if it could be built in the first place. Nuclear Lightbulbs would be a better option imo.

Edited February 21, 2014 by SargeRho

[RuBisCO]

From 0.1nm to 35nm, most particle however are 0.5nm. My estimation said that the common size at that altitude would be 2 nm.

Here is the source where is better explain the altitude and process.

So how about the density of particles at that altitude? From the charts in the book Venus Revealed the clouds end at 48 km (replaced by “thin haze†or “Virgaâ€Â) so your cloud city is literally but inside clouds of sulfuric acid.

What the point was is that the idea of going outside on Venus at that altitude with open skin is a bad idea, I think you agreed already. This is all counter to the idea of going outside in a vacuum, what I was getting at is: why do either? We can have machines working in either environment, and vacuum is more preferable to machines then working on the surface of Venus.

So you said that all elements can be extracted from 1 asteroid? Source?

Its a matter of logic, the C-type asteroids are the primordial material all the planets were made off, they have ALL the elements. And the methods I describe could theoretically separate any element for any other element within the energy usage limits I provided.

http://www.philipmetzger.com/blog/type-of-asteroid-to-mine-part-3/

" C Type accounts for about 75% of all asteroids. They formed in the outer portions of the asteroid belt closer to the frost line where it was cooler so carbon compounds could condense. They also contain hydrated minerals so we can get lots of water out of them. Some estimates are that we can get over 20% of the mass of the asteroid out in the form of water. Since chondrites are undifferentiated they also contain primitive metals, sometimes as much as 40% by mass. These would be extremely good asteroids to mine, having water, metals, and carbon compounds, all three in one. Because they are dark, they are rather hard to find."

http://www.uapress.arizona.edu/onlinebks/ResourcesNearEarthSpace/resources21.pdf

But machinary or robots would not have any problems with this, so only remains the g-factor. Or I need to quote the trieste and re-entry examples again?

No, machines are going to have problems with that, they are going to be very heavy machines, needing pressure chambers and heat pumps capable of maintaining nearly 500 K temperature differentials! There are extensive engineering challenges in making components capable of operating mechanically under those conditions. In Near Earth Space the engineering requirements are going to be significantly less.

I read Rendevouz with Rama and all its secuels 15 years ago. In this case such thing was made by the galaxy monitor.

We already had this at 1930:

http://tweedlandthegentlemansclub.blogspot.com.ar/2012/08/the-fabulous-interiors-of-hindenburg.html

http://www.nlhs.com/images/hindenburg/big_hindenburg_crew_mess.jpg

http://www.canadiancar.technomuses.ca/images/frise_chronologique-timeline/full/1930/Po-1930.jpg

Yeah and zeppelin travel was eventually found to be uneconomical, same will be for making a floating city on Venus when other options are cheaper and more economical like asteroid colonies.

90 years later, we have this in space:

http://www.nasa.gov/images/content/114305main_iss010e25228.jpg

http://spaceflight.nasa.gov/gallery/images/station/crew-34/hires/iss034e023541.jpg

So this means that when we would be able to make something like you said, then in venus we can have something 10 times better.

Hey and we should have atomic vacuum cleaners and flying cars by now to... see there is a difference from what is practical and viable from what is just daydreams: asteroid colonies are more practical and more likely then a Venus cloud colony. Although frankly both may end up at just dreams.

If we are going to limit this discussion to being practical enough to not terraform Venus and live in its clouds instead, we might as well ask why not be even more practical and not even live on Venus at all?

mined is the right word??

20ppm in the whole atmophere 92 bar. We need to know yet with accuracy how much it is in the cloud level. Then you need to add the water inside sulfure acid 150ppm that is mostly at cloud lv too.

Yes "mine" I guess we could call it "extract", We would need to suck in cloud particles, condense them, purify the sulfuric acid, undergo electrolysis, it would be rather energy intensive, at least more so then taking chunks of chrondrite asteroid, heating them in a solar ovens to 400 C and boiling out all the water at up to 20% per kg of raw material.

you mean the cost? of course it would be also reduce it. But the deltav it would be always the same.

No it is much higher, just to get out of Venus is going to take 10.3 km/s, you can get to some asteroids and back in less than that!

So now you are a especialist nuclear engineer? Where it said that is highly unstable? For earth we can have skylon, for venus it seems a good option.

Appeal to authority fallacy. One does not need to be a nuclear engineer to see the problems in a Nuclear Salt Water Rocket: first off the amounts of Plutonium, U235 or U233 it requires is prodigious, the nuclear salt water needs to be stored in geometry regulated, boron or neutron absorbing fuel tanks to prevent accidental criticality, hence 'unstable', and it will shoot out a beam of radioactive waste when operating. The practical, economical, political difficulties all of that entails means it not likely to happen.

One does not need to be a nuclear scientist to point that out, just as one does not need to be a mathematician to do basic mathematics.

First you was talking about bring asteroids from asteroid belt, then you speak about near object,

I was suggesting bringing an asteroid to earth orbit in counter to your claims of bring them on to Venus (why Venus, why not earth?) Ideally we go out to one in near earth space and only hull back refined material.

then I said that mostly all near object needs at least 5,4km/s, then you said that there is some with less. Now what? you need to find an asteroid that has all elements (I am not sure if that asteroid exist even in the asteroid belt) then it needs to have 2,2 km/s max deltav (less than earth escape velocity), and all the manuvers that you are using are the most low energy manuvers. So they take a lot of time. And time is money.I can use also the Interplanetary Transport Network if the time is not important.

With aerocapture you can kill 15km/s or more if you want.

My point is not simply in getting there, it is also is getting back, getting back from Venus alone is more delta-v then getting to and from most asteroids, and that not include cutting through venus's atmosphere.

Time is not simply money, fuel is too. And if your gong to talk about things like solar sails than your being contradictory counting the cost of time when many other forms of propulsion can get the job done much faster than solar sails. Also solar sails can't get one off venus, but they could easily be used around an asteroid.

I really need to answer this?? if in 2000 millons of years we still "alive", then is the sun the one that needs to move away of us.

This thread is talking about things like terraforming planets, a task that would take tens of thousands of years for Venus, might as well talk about solar system engineering to add billions of years of habitability to a system.

In jupiter? In jupiter clouds? No you cant. Gravity is too high.

Oh so you do have a practicality limit. Well sure a Jupiter colony would not be for the faint of heart, but anything is possible.

It seems that you are out of valid points, the only things that you do is repeat your self that an asteroid colony is more realistic with the hope you start to believe it.

And in my design I manage how to avoid all possible risks and how to collect energy at night. You would not find that in other place.

Well you fail to disprove my points or even acknowledge them. For example you devise complex schemes to extract energy when my solution is simply to have solar panels face the sun, no need to energy storage or multiple energy sources. No need to worry about much in the way of structure in building solar arrays kilometers wide in zero-gravity.

There is not enoght comets or asteroids to get that amount of water. And you would take a lot more to do.

The oort cloud is estimated to weigh in at 1.9 earth masses the amount of delta-v required to get out there would be less then the solar escape velocity from earth (42.1 km/s) of which much of that can be provided by a gravity assisted from Jupiter. Once out at an oort cloud comet, with only a few hundred meters per second of delta-v we could have it hurdling into the inner solar system. Sure all of this would take a few hundred years, but consider the time span for terraforming Venus would be in the tens of thousands of years it would be a viable option.

Heck we could probably grab just one plutoid like Eris or pluto its self, weighing less than Europa and having a higher percentage of water per ton, and send it flying into the inner solar system. Don't ask me how we move it, but technically it would be easier than Europa. Anyways we would have it smack Venus. The impact alone would likely knock off much of venus's present atmosphere. Eris for example weighs in at 12.5 times as much as all the water on earth, assuming just 10% of water which is probably an under estimate it would still weigh more then all the water on earth. Of course you would not want to be on or anywhere near Venus during such a collision of worlds, any cloud cities would need to be abondoned or suffer a trully epic death. but the new world produced afterwards would have a lot of water (all of a sudden), now in just one (or a handful of truly GRAND impacts) all the materials are present for terrafroming. The surface though would have become completely molten but its not like Venus has not done that before and probably recently in geological history (last few hundred million years), going back to its present crust thickness of just a few hundred meters would probably take only a few thousand years. A combination of solarshade and bio-chemical engineering as previously describe could probably bring Venus up to habitable in a few thousands years.

Highlighted because it is very relevent to the thread, for the people that think they can defeat rule 25 of the internet.

Yeah, that is tricky.

Wormholes... and maybe wizards.

I know that its name is Europa, but Europa here in spanish means Europe (continent), so I thought that maybe this planet was called Europa in reference to the continent´s name.

Both the continent and the moon were named after one of Zeus's aaah “Ladiesâ€Â. See with google you can learn something new everyday.

Winds dont blow right now at high speeds over the surfuce becouse the pressure, its all relative to the pressure. So almost all details of venus atmosphere at 50km 1bar should remain at venus surfuce 1 bar.

yeah I'm pretty sure climatology does not work like that! First of all the reason winds are slow on the surface has little to do with pressure, and everything to do with friction with the planet its self, its call Laminar flow. Honestly its anyones (other then a group of climatologist with a supercompueter) guess what kind of weather venus would have at 3 atmospheres of mostly nitrogen on a planet with a solar day of 4 months. I would hope it still super-rotates and I would put a good bet due to frictions with mountains and hills surface winds would be low, but that as far as I'm guessing.

Edited February 22, 2014 by RuBisCO

[SargeRho]

About a Jovian cloud colony: Jupiter's "Surface" gravity is only 2.4 times that of Earth. Most people can manage that.

[Rakaydos]

About a Jovian cloud colony: Jupiter's "Surface" gravity is only 2.4 times that of Earth. Most people can manage that.

Saturn would have closer to 1G, I believe...

[AngelLestat]

I will no answer word by word becouse I am getting tired. Besides, I explain all this several times already. If these notions can not enter in your heads, not blame me. I give many reasons with real examples.

Resume:

Venus floating cities colonization:

Cons:

1-Harder to start with the first manned mission, due to the extra deltaV to take off from 50km in comparison with asteroids, moon and mars.

2-The water is scattered in the atmosphere, this increase the difficulties for the first missions.

3-No easy to mine resources at the surfuce due to heat and pressure, this is a difficulty for the first missions.

4-Extra transit time needed to reach venus than moon.

5-Sufure acid scattlered in the atmosphere which forces to use antiacid covers and cloth to protect skin and materials from longer exposures.

6-No great amont of water, this is big difficulty in case we wanna start any terraform process.

Pros:

1-The most similar environment to Earth in the whole solar system, 0,9g, 1Bar and earth range temperatures.

2-At 50km altitude, venus atmophere provide better shielding againt sun or cosmic radiation than earth atmophere.

3-Very easy to float things in a CO2 atmophere; Air is a lifting gas, hidrogen provide a lot of lift. Less gravity than earth.

4-Constant horizontal wings that provide a 96hrs day/night cycle, High DV between winds at different altitud to provide a lot of energy.

5-Enoght water and all kind of resources to sustain a popullation like earth floating in the Venus clouds.

6-Venus gets 2 times more energy than earth. It can be harvested with solar cells pointing to any place due to the clouds refrectivity.

7-Sulfure acid very easy to get, this is main ingredient that any industry needs.

8-Shorted launch windows and transit times to any place in the solar system.

9-Thick atmophere which allows high deltav aerocaptures saving a lot of proppelent.

10-Locate some automated industries process on the surfuce to take advantage of the heat and pressure to decrease the cost of many developments products.

11-Once you have all infrastructure set, Venus has the potential to grow its economics faster than earth.

To understand all this cons and pross, we need to be able to see the big picture.

-Kg to orbit cost lows every year, this is equal also to the deltaV cost.

-Earth popullations growth, this can be only mitigated by global politics, epidemics, wars or equal distribution of resources and education (utopia, but internet may have the last word).

-Increase of the Non-renewable resources cost, each time is more difficult to extract them.

-There is not need for a an enterprice to be competitive from begining with the already established ones to start receive investments, support and some profits. And it might took from 1 to 100 years to remplace its competitors.

This last items are facts! If someone disagree, go and ask your concerns to someone else.

How to deal with 700K Temperature, 90 bar Pressure and sulfure acids.

To start I will remember again the Trieste, first manned submarine to reach 11 km depth (990 Bar) in 1960

Space craft reentry deal with temperatures of 7500K or more, also experiments of fussion or high power lasers also deal with great amount of temperature.

We deal with sulfure acids all days, in all parts of the world since ancient times. There is hundreds of materials that are inmune to acids.

So lets start talk about materials.

All carbon based materials resist +3000K (they not melt, sublime), this include Diamonds (for drilled tips), CNT, graphene the most resistent with +5000K. (sulfure acid affect some carbon based, but diamond are very resistent)

Platinum: Melting point 2000K (inmune to sulfure acids)

Deal with pressure has nothing to do with materials, is a design matter.

Any open shape like an hot air ballon envelope would not present any problems. In fact one of the design probes from geoffrey landis is a spheric hermetic ballon metal microns thick which contains water inside and nitrogen gas. So when the ballon entry in the atmosphere, how is low dense resist the reentry heat, then fall until reach higher pressures and temperatures, so the water start to boil and expand coutering the pressure. More heat equal to more internal pressure. So you dont have problems with external pressure.

Electronics: there is already 500K electronics, and we know already how to make 750K electronics. Carbon based materials, uranium oxide, valves, etc.

Someone mention a electric motor. Well you can remplace the copper with CNT wires to the coil. Then remplace the common coil varnish with another insulator, in case a different insultor presents problems with strenth or mechanical properties, then you may make the coils fix position and the magnets in the rotor.

Here there is a note about electric motors or other devices already test it for Venus aplications, with temperatures +800K.

http://www.unmannedspaceflight.com/index.php?act=Attach&type=post&id=23200

We can also have a liquid like water in a sealed container, when this is heated by the atmosphere, expand produce work (all kind of movements you want) and then you need to cool it again, for that you can use wind (surfuce 10km/h high density) mechanical energy without the need of any electrical device to produce movement. (Is easy to forget our oldest technologies).

About drill.. yes sure, how I explain you can use tons of materials for that, but one thing.. why you need to drill? You can detonate. That is the advantage of venus over zero g mining.

Another misunderstood from the graphics, is that if you are on haze cloud lv, you can not see nothing and you will melt by sulfure without cloth. The concentrations remains low. The visibility remains high. Here in earth we have a normal 40% humidity in the air.

At Venus that humidity made of water vapour and sulfure acid it would be close to 0.xx%. But the cloud had many km of height, so for that reason you can not see through them.

Rubisco, I guess these folks disagree with your point of view about airships. And they bet millons into this. You wanna rise your bet?

Airships are not so common at earth becouse oxigen, that was clear after the hidenburg disaster. So hidrogen is not allow. But they still have their place.

Long time ago zepellings dominated the sky (weird becouse aircraft came first, dont you?), Its strength was proved at war, dropping hundreds of bombs from an altutude where airplanes can not damage them. And if they did. 10 or 100 holes was not a big issue. That amount of hidrogen did not escape so fast. (you remember when you ask me how fast a city would sink with a rip?)

They can be good to transport big payloads without much fuel consuptions, there max velocity is 200km/h, but if they intercepts the high air currents, with that they can reach 400km/h.

The legs of that airship are great, they can work in the water, like overcraft, like suc-kers for high winds conditions and they can be deploy or opposite just suc-king the air.

You mention oort cloud, and type c asteroids, first I ask you to mention one asteroids that contains all elements, 4 or 8 elements are not all elements, you can manage well with 8 elements, but you would always needs something else. More with something so complex like a space habitat.

And the oort cloud does not enter in the discuccion becouse is absurd. I will no spend more details about it xd

I guess if you both put in my posicion to defend the idea, you can find all ways to counter those negative issues. But you just not want it.

PD: thanks for the europa info.

PD2:

About a Jovian cloud colony: Jupiter's "Surface" gravity is only 2.4 times that of Earth. Most people can manage that.

Yes sure, if their are Saiyajin, I guess they would not have any trouble.

Edited February 22, 2014 by AngelLestat

[SargeRho]

Dealing with pressure has everything to do with materials.

Spacecraft use ablative heat shields (these boil away slowly, pretty much all active spacecraft) or heat shields made of materials that can sustain extreme temperature gradients (space shuttle, X-37). These are designed to be subject to extreme heat for short periods. Also useless on Venus. The Trieste didn't have to deal with glass-weakening, solder-melting, people-toasting 500°C, only with pressure. These are thus utterly inapplicable examples.

Wether you use explosives or not, you HAVE to use drills. And good luck finding an explosive that won't auto-detonate already at 92 atmospheres/500°C.

[AngelLestat]

C4.. well that was fast dont you thing?

You can use drills if you want in venus like already explain. Why? there is something that I dint explain?

And my examples show you that, all problems even combined can be manage it, I thought in some of the solutions for those problems.. So if I can, then it would be a lot easier for a company with people working in this all days. So you dont have more excuses.. Accept it!! is a facinating idea

[SargeRho]

C4 detonates under Venusian surface conditions.

And the issue isn't if problems can be overcome. The issue is can they be overcome ECONOMICALLY. Is it worth overcoming them, or doing something else instead? I still don't think a venusian cloud colony is worth the trouble. Fascinating, yes. Maybe even plausible. But realistic? Nope.

[RuBisCO]

AngelLestat,

For cons you forgot

1. High delta-v to return, though atmosphere no less.

2. Requires heat shield to enter

3. Mass of surface equipment increased by having to deal with extreme pressure and temperatures, this is a perpetual difficulty.

Rubisco, I guess these folks disagree with your point of view about airships. And they bet millons into this. You wanna rise your bet?

Another appeal to authority. Yes I'll bet they are wrong. Its been nearly 80 years now and air-travel is nearly completely dominated by airplanes and helicopters, airships are the vinyl records of the shy.

And again the C-type asteroids have ALL the elements, in fact any rock has ALL the elements its just a matter of concentration. C-type asteroids being the undifferentiated material the started the solar system, have all the elements, at least in concentrations of a few dozen parts per billion for the most rarest (and most rarely used) elements, enough to be extracted and separated by the technique I describe of solar thermal vaporization in low pressure hydrogen reducing atmosphere followed, electrowinning in a fluoride or chloride molten salt, within the energy limits I describe (based on vaporizing iron and electrolysis). We are talking of a good overestimate of 50 kw/hour per kilogram (Aluminum electrolysis is 15 kw/hr per kilogram) at least half of that energy provided by solar concentrators afloat in zero gravity. That right no giant windmills high in venus atmosphere, no generators operating at 500 C at 92 atmospheres, just a thin Mylar like foil. You on the other hand need rather "innovative system" and heavy for having a mining, ore processing, refining, all over Venus mining at different ore deposit, utilizing at least megawatts if not gigawatt, nearly everything operating at least a 500 C and 92 atmospheres. My solution is simpler, cheaper, more practical.

.... Back on topic:

And what is wrong with the oort cloud? Add up the delta-v needed to pull water off of europa, out of jupiter's gravity well, out of Jupiter space and to Venus, verse flying out to a comet and nugging it into free-fall into the inner solar system. And we don't need to go that far there are plenty of comets or other concentrated volatile material objects only as far as Neptune space, with no gravity wells to climb out of. The only hindrance is size, now if hundreds of thousands of small impacts of just a few kilometer wide comets can do just as good of a job as a few world colliding impacts of smacking plutoids into Venus, so be it. The Delta-V required in pushing either would be small. Pluto for example has an orbital speed of 4.7 km/s, so to get it to crash into the sun would require 4.7 km/s, to get it to crash into Venus would require a little less. Further out the amount of Delta-V required is less (but time goes up). Of course moving a comet of a billion tons a few hundred m/s over the course of decades could be done with multi-terrawatt fusion engines or that nuclear salt water engine, you would just need 10 million of said comets, each roughly 100 km wide, but only a single planitoid/eer I mean "dwaft planet" of 10^19 tons, I don't know maybe the starship enterprises D with its "multiphase tractor beam" or some other BS.

So lets take pluto (what good is it anyways?) and somehow smack nearly all 1.3*10^22 tons of it, which is made of roughly 10-50% water or 93%-464% all the water on earth, into Venus. What would we get? Well a few percents of that mass would be blown off in the impact, this would include much of Venus present atmosphere, if we impact at an angle to the equator we could also impart a fair amount of spin to venus, perhaps a spin of just a few earth days in length instead of its present spin of ~4 earth months should be possible (a pluto size body impacting venus at radius length from venus at 45 km/s would impart a spin of 3.7 days, that without taking into account angular momentum which means only the mass at the surface of venus at equator is at full spin, not all of venus's mass). Shallow enough of a impact we might be able to make a tiny moon around Venus as well if we wanted, definitely a ring for a few thousand years. Venus would become a molten mass until its crust cooled after a few thousands years, assuming we also built a solar shade. The oceans would rain down, new Venus would likely be remarkably flat, an ocean world until it crust got thick enough to support continents which would take millions of years. Assuming I'm wrong and some of Venus crust remains intact to form islands right way (around the poles?) Venus would be perfectly habitable thousands of years after impact, with a solar shade letting in controlled amounts of sunlight.

Perhaps it would be best to smack smaller bodies into a venus, really bigger comets, to get the right ratio of spin imparted, atmosphere knocked off and water/hydrogen delivered, without destroying enough of the crust to require thousands of years of cooling and render the planet into an ocean world. Of course Venus equator would take most of the punishment so expect at least that area to be melted flat. Let see assuming a density of 1.3 tons/m^3 and 70% water that would require 50,000, 40 km wide impactors, or 3000 impactors of 100 km wide to equal all the water on earth. It would require only 120, 300 km wide impactors (at 50% water and 1.7 tons/m^3). There should be enough bodies of these sizes in the Kepler belts alone, forget the Oort cloud.

In fact the more I think about this the more just smacking Venus with 500-500,000 comets totaling roughly 10^22 kg is a really great way to terraform Venus!

1. It will impart spin, how much, well that a good physic test question:

1000 impactors each weighing in at 1*10^19 kg impact Venus's surface at the equator a full radius from the center of Venus, each impactor is traveling at 50 km/s upon impact. Venus has a mass of 4.867*10^24, assume angular momentum of a sphere and 50% of the mass of the impactors imparting angular momentum, how much spin would Venus gain in m/s, and in revolutions per hour?

My guess based on velocity imparted just from a direct strike is that a total spin will be less than 2 day. This is because a direct strike would impart 267 m/s change in Venus's velocity, calculate that velocity over Venus circumference equals a 40 hour long day.

2. That spin imparted will not be uniform, a magnetic field would arise!

Even after a more accurate measure of its spin is calculated from angular momentum of a sphere, it still won't account for a difference in density of Venus at depth as well for fluid motion of Venus's mental, crust and core. It is likely a spin up of Venus's surface will not translate directly throughout, the surface will end up spinning slightly faster then the core, this difference in spin would generate a magnetic field (sort of like on earth) which would protect Venus from solar striping over the long run.

3. Blow off Venus atmosphere.

These impacts at such an angle could also end up blow off a good percentage of Venus's atmosphere. When each impact strikes against the equator a wave of venus's atmosphere will be blown off into space. This of course would also start blowing off what was already added to venus's atmosphere from previous impacts, so we can strip all of Venus's atmosphere in this manner, only a percentage, I would just throw a number out there an say we could get ride of 50% of Venus's atmosphere this way tops.

4. Adding all the required water, plus more.

All the water of earth, plus more, hopefully all the residual CO2 can be converted to solid carbon and carbonates. Venus may end up with even more nitrogen though. Venus would after all these impacts likely still have 2-4 atmosphere air pressure of almost all nitrogen gas.

Problems: how to move that many gigantic comets, how not to have all of Venus's surface melt down flat.

Edited February 23, 2014 by RuBisCO

[AngelLestat]

C4 detonates under Venusian surface conditions.

And the issue isn't if problems can be overcome. The issue is can they be overcome ECONOMICALLY. Is it worth overcoming them, or doing something else instead? I still don't think a venusian cloud colony is worth the trouble. Fascinating, yes. Maybe even plausible. But realistic? Nope.

Look I respect your opinion.

I think that the first mining steps (and they would be more like practice than to get real benefics) it would be the Moon short followed but some asteroids.

Then at the same time we would have some manned missions to mars, I am not sure if an small colony would try to settle or not in the comming years.

After that, the first plans to start a colony at venus would appear, all with small steps. But when the colony is already settle, after that all steps would be big, it would not take much time to overcome the small mars colony first, then moon, and near asteroids habitats. Becouse the venus potential is bigger if we see the big picture.

About C4, I watch a MythBuster episode some time back, where they try to detonate C4 without the detonator. They could not.

They sink the c4 in melt thermit (that is close to 2000k), then they shot it with all kind of guns, they crushed dropping a heavy weight from height, etc.

Until they ask to an expert why they could not detonate. Becouse that is the main reason of the explosive, to be super safe, it was made for that.

You can only detonate with EXTREME HEAT and a SHOCKWAVE. Read about it.

AngelLestat,

For cons you forgot

1. High delta-v to return, though atmosphere no less.

2. Requires heat shield to enter

3. Mass of surface equipment increased by having to deal with extreme pressure and temperatures, this is a perpetual difficulty.

I dint.

Your number 1 is also my number 1. You need 8,5km/s to reach orbit. (but there are methods to reduce that, then if you count how much easy is get orbit each year, it reachs the point where is only the fuel price and the management cost.

Your number 2. Why I need to be in the list?? its almost irrelevant from the mass point of view. I can kill 6000 or 12000m/s if I want in venus atmosphere. How much fuel you would need if you want kill that speed without aerocapture?

Also depends on the design and density. For example skylon does not have a heat shield.

Your number 3. Why the mass increase? Is not a manned vehicle!!! You dint see the new desigs for the new venus rovers???

http://upload.wikimedia.org/wikipedia/commons/1/15/Venus_Rover.jpg

http://www.nasa.gov/images/content/681522main_Landis_Image_2012-1.jpg

Those are massive for you?

Of course a mined vehicle needs to be massive, but just equal massive like any other vehicle at mars or machinery at asteroid belt.

And any problems mining in the surfuce of venus that you need to have into account, is highly countered by the benefic of mining at 0.9g

Another appeal to authority. Yes I'll bet they are wrong. Its been nearly 80 years now and air-travel is nearly completely dominated by airplanes and helicopters, airships are the vinyl records of the shy.

But you dint see the videos, before talk you need to understand why old airships fail, and why this one has so much to offer.

Helicopters cant carry bigger or heavy payloads, besides the fuel consumption is 8 or 10 times higher.

Airplanes needs a good landing strip. They can not carry big payloads and fuel consumptions is 6 times more.

Normal zeppelings needs ballast and other things to land.

This one can land in water or any way. It does not have those problems.

It can be also used with turism transport or entertainment. Is like said that cruises has not profits becouse airplanes are fast.

And again the C-type asteroids have ALL the elements, in fact any rock has ALL the elements its just a matter of concentration.

What happens if you need bigger amounts of that ppm material? Or you need to wait to mine all the asteroid before star construct the things that you need?

(Aluminum electrolysis is 15 kw/hr per kilogram) at least half of that energy provided by solar concentrators afloat in zero gravity. That right no giant windmills high in venus atmosphere, no generators operating at 500 C at 92 atmospheres, just a thin Mylar like foil. You on the other hand need rather "innovative system" and heavy for having a mining, ore processing, refining, all over Venus mining at different ore deposit, utilizing at least megawatts if not gigawatt, nearly everything operating at least a 500 C and 92 atmospheres. My solution is simpler, cheaper, more practical.

Are you joking XD? First, 15kw/h per kilogram. That seems very energy inneficient taking into account that is 1kg, I dont know how you see it...

Then you think that harvester energy far from the sun is easier than a mechanical windmill? "innovative system????? lol"

In this case the high pressure is a benefic, you have low wind speed (perfect for mills) with high density (more energy for unit of area).

The venus surfuce heat you use it to boil the water or any similar liquid.

And what is wrong with the oort cloud? Add up the delta-v needed to pull water off of europa, out of jupiter's gravity well

I never said move europa, I just take it like a theorical example in case something similar (with europa amount of water) it would be orbiting venus.

And the only idea that I drop in that case was shot the water using a noozle from the surfuce to venus.

But in case that you have a moon that is almost 80% water (maybe enceladus), it would be a lot more efficient try to move enceladus away from saturn than find, reach and move an amount of asteroids that equals enceladu´s water from asteroid belt or oort cloud.

and what do you mean by free fall? All things that are in orbit are in free fall. You need to slow their orbital velocity. You can use enceladu water like reaction mass for a nuclear or fussion engine. Oort Cloud is very very far.

each roughly 100 km wide, but only a single planitoid/eer I mean "dwaft planet" of 10^19 tons, I don't know maybe the starship enterprises D with its "multiphase tractor beam" or some other BS.

Is just a matter of scale up, instead put millons of fussions reactors over all asteroids in oort cloud, you may put those millons reactors in enceladus.

But something is clear, it does not worth it, the only solution is like I thought, try to use the exhaust velocity of a fussion engine to send all the water. Maybe there is way to focus those particles. But still, always we talk about move things, it require energy, and if those things are massive like planets, it does not matter what you do. It will require an amount of energy according the mass you want to move.

if we impact at an angle to the equator we could also impart a fair amount of spin to venus, perhaps a spin of just a few earth days in length instead of its present spin of ~4 earth months should be possible (a pluto size body impacting venus at radius length from venus at 45 km/s would impart a spin of 3.7 days, that without taking into account angular momentum which means only the mass at the surface of venus at equator is at full spin, not all of venus's mass)

I dont see with good eyes any impact strategy, you would need to wait millons of years to the planet recover from the impact. With a lot of collateral problems.

And what happen if 1000 years after the impact you realize that there is a better way to do it? XD

Venus would be perfectly habitable thousands of years after impact, with a solar shade letting in controlled amounts of sunlight.

Check how much time the earth take to cold before the "moon" impact.

Perhaps it would be best to smack smaller bodies into a venus, really bigger comets-.....

1000 impactors each weighing in at 1*10^19 kg impact Venus's surface at the equator a full radius from the center of Venus, each impactor is traveling at 50 km/s upon impact. ....

My guess based on velocity imparted just from a direct strike is that a total spin will be less than 2 day. This is because a direct strike would impart 267 m/s change in Venus's velocity, calculate that velocity over Venus circumference equals a 40 hour long day.

Sorry, I dint follow you in your math to see if is ok or not, just becouse I dont believe that crash things into venus is the way to go.

You dont need to forget the atmosphere, is so thick that if you crash small sizes asteroids into venus they would not reach the ground, for that reason venus has no visible craters. You would just heat the venus atmophere even more. And if you crush things, the most possible is that you remove the little amount of water that venus has first. Those are 15000km3 of watter, so you have a lot of asteroids there.

2. That spin imparted will not be uniform, a magnetic field would arise!

3. Blow off Venus atmosphere.

4. Adding all the required water, plus more.

All the water of earth, plus more, hopefully all the residual CO2 can be converted to solid carbon and carbonates. Venus may end up with even more nitrogen though. Venus would after all these impacts likely still have 2-4 atmosphere air pressure of almost all nitrogen gas.

Problems: how to move that many gigantic comets, how not to have all of Venus's surface melt down flat.

And all those huge problems just to try to impose a 24hs spin. When the airwinds already give us 96hs spin.

We need to forget terraform venus, all those matters are impractical (taking the advantage you get) even if we have free energy.

The problem is that we se all from earth perspective. But maybe Venus has more benefics being like that, than similar to earth.

We must learn to take the good things and not try to change the bad according to our tastes.

That is equal true for planets like people.

Our social problems are always to try to change the ambient to our needs instead try to fusion us with the ambient.

Edited February 23, 2014 by AngelLestat

[Seret]

About C4, I watch a MythBuster episode some time back, where they try to detonate C4 without the detonator. They could not.

They sink the c4 in melt thermit (that is close to 2000k), then they shot it with all kind of guns, they crushed dropping a heavy weight from height, etc.

Until they ask to an expert why they could not detonate. Becouse that is the main reason of the explosive, to be super safe, it was made for that.

You can only detonate with EXTREME HEAT and a SHOCKWAVE. Read about it.

C4 is not magical, it's just a high explosive. Generally yes, most explosives are deliberately quite insensitive. To get a full detonation you will require a very high velocity shock wave. Nothing else will do. However, not only are most explosives themselves flammable (soldiers have been known to use small pieces of plastic explosives for cooking if they have nothing else available) but they will undergo a reaction called deflagration if they get too hot. Deflagration is effectively very rapid burning, unlike detonation which is a specific and much more energetic chemical reaction. However, if you were standing near to it a deflagration feels and looks about the same as detonation, and deflagrating HE can and will induce sympathetic detonation in nearby explosives.

People whose day job involves proximity to high explosives (such as myself for several years) tend to be quite careful about avoiding fires, as things will go bang. You would absolutely not want to expose any high explosive to the Venusian atmosphere.

[AngelLestat]

Hi Seret, thanks for the extra data. I really appreciate your knowledge on the subject.

Yes, now that I remember, they mention that you can also use it to cook. In fact, I guess some time they measure what fuel was more effective in mass/calories to heat water (c4 was there).

But that reaction does not need oxygen?

At venus we have 450Celcius at the surfuce but without oxygen, and it will be all manage it by remote controlled machinery from the clouds cities. Is not that safe enoght?

The problem come I guess with the detonator, is the detonator heat resistent? It would be possible to make a detonator heat resistent in case is not?

PD: interesting work yours, I will like to know more.

[Seret]

is the detonator heat resistent?

Absolutely not. There are two main types, electric and non-electric. The non-electric ones literally have a burning fuse shoved into them, so you can see why they aren't going to enjoy the heat. Sadly even the electric ones actually work by heating of a wire, so they don't like getting warm either. Dets are nasty little buggers, and not to be trusted.

The problem is that the only way to reliably set off a large, safe, insensitive charge is by smacking it with another explosive. In practice this means you need what's called an explosive train, where you use a very small amount of a very sensitive substance to initiate a larger amount of more insensitive stuff, all the way up until you have something big enough to set off the main charge. So you are always going to need a certain amount of the really dodgy material. Not that this matters, because even the really insensitive stuff like C4, TNT and ANFO can't handle Venusian temperatures. At the very least, they'd rapidly decompose which tends to exude less stable products such as nitroglycerine, of which I'm sure you're aware.

[RuBisCO]

Your number 1 is also my number 1. You need 8,5km/s to reach orbit. (but there are methods to reduce that, then if you count how much easy is get orbit each year, it reachs the point where is only the fuel price and the management cost.

Lots of launch windows don't make a price go down,

Your number 2. Why I need to be in the list?? its almost irrelevant from the mass point of view. I can kill 6000 or 12000m/s if I want in venus atmosphere. How much fuel you would need if you want kill that speed without aerocapture?

Also depends on the design and density. For example skylon does not have a heat shield.

A heat shield can be 15% of the mass, as well has having a ship designed to withstand the heat and the Gs. Asteroid colonies don't need aerocapture, there is no gravity well to fall down, the ships can be flimsy solar sails. Skylon has yet to fly.

Your number 3. Why the mass increase? Is not a manned vehicle!!! You dint see the new desigs for the new venus rovers???

http://upload.wikimedia.org/wikipedia/commons/1/15/Venus_Rover.jpg

http://www.nasa.gov/images/content/681522main_Landis_Image_2012-1.jpg

Those are paper rovers, not actually built. A robot on the surface will need a pressure vessel (heavy) for pressure sensitive components like capacitors, optics, etc, cooling system (heavy) a powerplant for the cooling system (heavy). A robot that can operate at 500 C and 92 atm will require a lot of advance engineering, advance engineering aim at a rather esoteric task (operation on Venus)

Those are massive for you?

Of course a mined vehicle needs to be massive, but just equal massive like any other vehicle at mars or machinery at asteroid belt.

No a mining vessel on an asteroid does not need to be massive, first off the 1.4 g/ml rock is soft and does not require big and heavy crushers, the machines do not need to support their own weight for they have virtually none.

And any problems mining in the surfuce of venus that you need to have into account, is highly countered by the benefic of mining at 0.9g

There is no benefits of mining at 0.9gm there are many benefits to mining at 0g though, as I explained.

But you dint see the videos, before talk you need to understand why old airships fail, and why this one has so much to offer.

Helicopters cant carry bigger or heavy payloads, besides the fuel consumption is 8 or 10 times higher.

Airplanes needs a good landing strip. They can not carry big payloads and fuel consumptions is 6 times more.

Normal zeppelings needs ballast and other things to land.

This one can land in water or any way. It does not have those problems.

It can be also used with turism transport or entertainment. Is like said that cruises has not profits becouse airplanes are fast.

And it is huge and requires massive expensive storage facilities and investment.

What happens if you need bigger amounts of that ppm material? Or you need to wait to mine all the asteroid before star construct the things that you need?

Why would they need it in big amounts? Take ruthenium for example, all the worlds production is under 40 tons a year, it is not needed much. But lets go with that logic, why would they on Venus not also for some reasons need "bigger amounts" of a rare earth mineral: how would they mine it? Scorer the surface of Venus for a good ore source, build specialty extraction system for extracting it from the ore. The asteroid mine on the other hand can start TRADING resources mined for other resources and equipment from earth, unlike the Venus colony which is mainly a one way trip. The asteroid mine can on just one spot (the asteroid) get EVERYTHING, While the Venus colony is going to need mines all over Venus different ores.

Are you joking XD? First, 15kw/h per kilogram. That seems very energy inneficient taking into account that is 1kg, I dont know how you see it...

Google the energy cost of aluminum production.

Then you think that harvester energy far from the sun is easier than a mechanical windmill? "innovative system????? lol"

Near Earth Space is not far from the sun, it going to be between 500-2000 W/m^2 of solar flux. Remember these asteroids can even cross Venus's orbit.

In this case the high pressure is a benefic, you have low wind speed (perfect for mills) with high density (more energy for unit of area).

The venus surfuce heat you use it to boil the water or any similar liquid.

If you boil water on venus's surface, how are you going to cool it and close the cycle, you need to pump the steam up 50 km to cool it down.

I never said move europa, I just take it like a theorical example in case something similar (with europa amount of water) it would be orbiting venus.

And the only idea that I drop in that case was shot the water using a noozle from the surfuce to venus.

But in case that you have a moon that is almost 80% water (maybe enceladus), it would be a lot more efficient try to move enceladus away from saturn than find, reach and move an amount of asteroids that equals enceladu´s water from asteroid belt or oort cloud.

I don't know about that: you have to consider the delta-V needed to get out of Saturn's gravity well. Also again Keplar space is good enough. There are plenty of Enceladus size bodies there (you would need at least 10 of them). Orbits closer to the sun require more delta-v to drop down than orbits further from the sun, and since terraforming Venus is going to a many thousands of year process anyways just for all the heat rejection and complete repocessing of the planet titanic atmosphere, time is not a consideration.

and what do you mean by free fall? All things that are in orbit are in free fall. You need to slow their orbital velocity. You can use enceladu water like reaction mass for a nuclear or fussion engine. Oort Cloud is very very far.

Again Keplar Belt is good enough. What I mean is that an object like Pluto needs less then 5 km/s to completely cancel out all its orbital velocity, it would then drop straight into the sun, a little less to fall as low as Venus space. The further the object is from the sun the less delta-v is needed to do this. An object orbiting Saturn would need to first get out of Saturn orbit (unknown delta-v), and then would need twice as much delta-v for pluto to fall to venus space. An object orbiting jupiter would need to first get out of Jupiter orbit (unk delta-v) and then would need three times as much delta-v.

Is just a matter of scale up, instead put millons of fussions reactors over all asteroids in oort cloud, you may put those millons reactors in enceladus.

But something is clear, it does not worth it, the only solution is like I thought, try to use the exhaust velocity of a fussion engine to send all the water. Maybe there is way to focus those particles. But still, always we talk about move things, it require energy, and if those things are massive like planets, it does not matter what you do. It will require an amount of energy according the mass you want to move.

Again even if you want to just send the water (magically) your still talking about 10^21 kg of water. Extracting and using star trek teleporters to move the water from a body that is 80% water will have saved you only 20% is mass, for the added cost of a extracting system to extract all the water.

I dont see with good eyes any impact strategy, you would need to wait millons of years to the planet recover from the impact. With a lot of collateral problems.

And what happen if 1000 years after the impact you realize that there is a better way to do it? XD

You would not need to wait millions of years (assuming the whole crust is not molten). The surface of a planet can lose several dozen degrees in just a night! That temperature loss can go down through 2 meters of soil in just a few months. Imagine Venus with a sunshade shadowing the whole planet, it would cool down very rapidly, in just a few centuries at least. The only problem is the rate and size of the impacts, the really big ones could melt the whole crust of the planet, and if this allows convection of heat liquidity from below it would really slow cooling down.

Check how much time the earth take to cold before the "moon" impact.

We aren't impacting the moon, at least not in just one impact.

Sorry, I dint follow you in your math to see if is ok or not, just becouse I dont believe that crash things into venus is the way to go.

You "believe"??? This is religion and not science?

You dont need to forget the atmosphere, is so thick that if you crash small sizes asteroids into venus they would not reach the ground, for that reason venus has no visible craters. You would just heat the venus atmophere even more.

a 100 km wide body traveling at 50 km/s will penetrate through Venus atmosphere! There are in fact impact craters on venus: http://www.solarviews.com/eng/vencrate.htm

And if you crush things, the most possible is that you remove the little amount of water that venus has first. Those are 15000km3 of watter, so you have a lot of asteroids there.

That nothing, we are talking about delivering 10^21 to 10^22 kg of water to venus, one hundred thousand to one million times greater amounts of water then is already there.

And all those huge problems just to try to impose a 24hs spin. When the airwinds already give us 96hs spin.

We need to forget terraform venus, all those matters are impractical (taking the advantage you get) even if we have free energy.

The problem is that we se all from earth perspective. But maybe Venus has more benefics being like that, than similar to earth.

Now you want to talk practical? Well I recommend going to or starting a thread about "colonizing Venus the way it is" and leave this thread about Terraforming Venus.

We must learn to take the good things and not try to change the bad according to our tastes.

That is equal true for planets like people.

Our social problems are always to try to change the ambient to our needs instead try to fusion us with the ambient.

I really don't think "fusion us with the ambient" is a good idea, I don't think living in a tribe out in nature, constantly warring with my neighboring tribes, murder each other and dragging the women back kicking and screaming is a good idea. No changing the world for our convince has overall been a benefit, then again it has allowed us to populate into the billions, I guess we could murder 99 out of 100 people so that 1% can go back to living in "harmony with nature", either that or we keep with progress and technological development and try to build better worlds.

Edited February 24, 2014 by RuBisCO

[AngelLestat]

Absolutely not.

Lol, you are not helping seret, and you are the specialist. Think out of the box for 1 min please.

Yesterday, I was thinking in the detonator problem, becouse I know before you answer that it will represent an issue.

So I imaging an electrical resistance inside a high pressure container with a liquid. Then if you heat the liquid to very high temperatures you would have a shockwave in conjunction with heat. But I was not sure of how much m/s that shockwave would be.

Today I see your answer, it seems that the c4 melting point it was also a issue.

But comming back to my idea, I thought that if I was correct it was very probably another came with this idea before me.

And tadan...

http://www.google.com/patents/US1408565

Then, if exist such detonator then it means that there is a explosives for high temperatures. The answer is yes "BTDAONAB"

http://www.wydawnictwa.ipo.waw.pl/cejem/vol-9-3-2012/Agrawal.pdf

It can be used for very deep drill holes, so they need to stand temperatures until 500Celcius and high pressures.

This one, stand 550Celcius and 300000Bar (How I said, deal with pressure is not a big deal).

So, problem solve. And I think if chemist know that they dont need to worry for the oxygen (a big oxidant element) they could find many different solutions.

Lots of launch windows don't make a price go down

?? read again please. When I said how much easy is to reach orbit each year, I meant the cost due to technologies or just for practice in the matter. It has nothing to do with launch windows. But now you mention, that also reflects into the cost some how.

A heat shield can be 15% of the mass, as well has having a ship designed to withstand the heat and the Gs. Asteroid colonies don't need aerocapture, there is no gravity well to fall down, the ships can be flimsy solar sails. Skylon has yet to fly.

Really? in what year? 1960 comming back from the moon to super speed?

Well never mind, lets said that is like you said. If 15% is what do you need to earth, then for the same speed you need almost the half of that in venus.

And now we have a lot of better materials, and like I said, it depends also of the design and density.

You have inflatable heat shields, does decrease a lot your density by unit of area. Also the same inflatable heat shield can work like ballon once you are at 50km height.

Those are paper rovers, not actually built. A robot on the surface will need a pressure vessel (heavy) for pressure sensitive components like capacitors, optics, etc, cooling system (heavy) a powerplant for the cooling system (heavy). A robot that can operate at 500 C and 92 atm will require a lot of advance engineering, advance engineering aim at a rather esoteric task (operation on Venus)

Lol, you think those rovers are just a draw??? You think that Geoffrey Landis and its team are just a regular internet guys?

It works in the NIAC, high advance nasa concepts. Read his curriculum, He design many rovers or different aplications that was used in many of the nasa missions.

AND PLEASE STOP WITH THE PRESSURE ISSUE!! IS NOT AN ISSUE!!!

Yes..!! Humans can die with that pressure, The max is 33 bar, but if you overseed that you die for chemicals reasons, no due to pressure.

For example Cachalot are mammals like us, this is mean they had air inside its lungs (pressure problem if you change from high pressure to light pressure quick or vice versa.), but nonetheless, they can immerse to 3km of deep (250Bar) for search food. And their limits is not becouse pressure, Is becouse they can hold their breath 90min.

No a mining vessel on an asteroid does not need to be massive, first off the 1.4 g/ml rock is soft and does not require big and heavy crushers, the machines do not need to support their own weight for they have virtually none.

There is no benefits of mining at 0.9gm there are many benefits to mining at 0g though, as I explained.

You think that all asteroids form from dust? Asteroids were parts of stars or other planets, they have metals portions more dense than we can find at earth.

Do you like to read about asteroid mining, but you never read how difficult it is. What are the problems that you need to deal.

First, anything that we know about mining at earth or different methods, etc. Do not work in space.

Second a simple drill, if you dont fix your tool to your asteroid (this is mean extra holes that you need to do), the only one that will turn it will be you, or your spacestation.

Third, you need always something to push against. That is super easy in a planet with gravity (that is becouse all transports vehicles are 10000 more efficient than any space vehicle). How you move all the material that you extract? How you keep all material in one place without float around and lost it?

You can not su.ck them becouse there is not air. You can not use a simple conveyor belt becouse you dont have gravity.

There is ways to solve these problems, but you always need to deal with the fact that you dont have something to push against.

And it is huge and requires massive expensive storage facilities and investment.

So? they still have a product which has not competitors in what it does. One advice, always tries to delegate any economic decision.

Why would they need it in big amounts? Take ruthenium for example, all the worlds production is under 40 tons a year, it is not needed much. But lets go with that logic, why would they on Venus not also for some reasons need "bigger amounts" of a rare earth mineral: how would they mine it? Scorer the surface of Venus for a good ore source, build specialty extraction system for extracting it from the ore. The asteroid mine on the other hand can start TRADING resources mined for other resources and equipment from earth, unlike the Venus colony which is mainly a one way trip. The asteroid mine can on just one spot (the asteroid) get EVERYTHING, While the Venus colony is going to need mines all over Venus different ores.

I am not talking about very rare elements, I am talking about elements that you may need in big amounts and you do not have enoght. Maybe carbon, calcium, magneso, sulfure, lithium, potacium, argon, xenon, sulfur, phosphorus, sodium, etc.

Besides, a C type asteroid "may" be compound of many elements, but in any place it said that has all. No even in small amounts.

Is like in the planets, if you mine one place you will find that you have a lot of some components and almost nothing of others.

The same happen with asteroids becouse they form in a similar way. Meanwhile at venus you can search in other place, in your space mining station you need to go and search another asteroid, or wait to be sent from the earth (9,5km/s just leo).

Google the energy cost of aluminum production.

I am not saying that asteroid mining has no benefics or profits. I never said that. But asteroid mining does not solve all earth problems. In the same way than an airplane can not solve all transport problems. You got that?

If you boil water on venus's surface, how are you going to cool it and close the cycle, you need to pump the steam up 50 km to cool it down.

?? So why I mention the mechanical windmill? It was not for electrical purpose. It was to produce work. This work would cold the water so the cycle can continue.

In fact, water start to boil at 300celcius at 90 bar. Now you just need a liquid than the boiling point at that pressure were close to 400Celcius and ready, you have a very efficient work transference cycle.

I don't know about that: you have to consider the delta-V needed to get out of Saturn's gravity well...

What I mean is that an object like Pluto needs less then 5 km/s to completely cancel out all its orbital velocity

I put that in hold, I will do the math to compare both cases. Then I tell you.

Again even if you want to just send the water (magically) your still talking about 10^21 kg of water. Extracting and using star trek teleporters to move the water from a body that is 80% water will have saved you only 20% is mass, for the added cost of a extracting system to extract all the water.

What adding cost? the same propulsion system that you can use to move a massive object, it will be the same than shot all that water in the right direction.

With this approach you only move the water, not the whole planets with its core, grounds, etc. How much % of water has europa or pluton?

You would not need to wait millions of years (assuming the whole crust is not molten). The surface of a planet can lose several dozen degrees in just a night! That temperature loss can go down through 2 meters of soil in just a few months. Imagine Venus with a sunshade shadowing the whole planet, it would cool down very rapidly, in just a few centuries at least. The only problem is the rate and size of the impacts, the really big ones could melt the whole crust of the planet, and if this allows convection of heat liquidity from below it would really slow cooling down.

The surfuce yes.. But here you need to take the atmosphere. After the moon formation, is estimated that earth took 10 millons years to cold down.

This is becouse most of its gas and water remains covering all earth with clouds, so then you need to take into account the temperature of clouds like surfuce at high altitude, this is mean low temperatures at high altitude but really high temperatures in the surfuce.

Now you want to talk practical? Well I recommend going to or starting a thread about "colonizing Venus the way it is" and leave this thread about Terraforming Venus.

You are wrong, these ideas are about terraforming venus. We are rising its ground lv to heights with more habitable conditions.

After that we can start to convert the co2 of direct way without use water. But is less efficient than use a replicator like plants.

I really don't think "fusion us with the ambient" is a good idea, I don't think living in a tribe out in nature, constantly warring with my neighboring tribes, murder each other and dragging the women back kicking and screaming is a good idea. No changing the world for our convince has overall been a benefit, then again it has allowed us to populate into the billions, I guess we could murder 99 out of 100 people so that 1% can go back to living in "harmony with nature", either that or we keep with progress and technological development and try to build better worlds.

i dont care :S, And you have a psicologic issue if you interpret all my words this way.

When I mention education problems, you start to talk about poor countries and discrimination.

Now I said fusion with the ambient and you talk about kill 99% of the populate.

I will not even bother to explain this.

Edited February 24, 2014 by AngelLestat

[SargeRho]

"they still have a product which has not competitors in what it does."

And what would that be?

"Maybe carbon, calcium, magneso, sulfure, lithium, potacium, argon, xenon, sulfur, phosphorus, sodium, etc."

All of which, exept xenon, are very abundant on Earth.

[Rakaydos]

is Lestat still talking about interplanetary trade?

Not going to happen. Any planetary mining (of ANY body) is not going to be profitable enough to ship to other worlds.

Small asteroids might be profitable because of the lack of gravity, but even the large ones like Ceres and Vesta are too big to economically mine.

[Dispatcher]

Ceres is a minor planet; similar to Pluto. It is largely an ice body, not like most objects in the asteroid belt. So mining of it, per se, would not be profitable, unless you want to haul its water to another location. Vesta is the largest known asteroid, in terms of composition.

[Seret]

Yesterday, I was thinking in the detonator problem, becouse I know before you answer that it will represent an issue.

So I imaging an electrical resistance inside a high pressure container with a liquid. Then if you heat the liquid to very high temperatures you would have a shockwave in conjunction with heat. But I was not sure of how much m/s that shockwave would be.

There's a reason you need an explosion to trigger a secondary or tertiary explosive. Det cord (which is how you often set things off) is typically about 7000m s^-1. Back to the drawing board for your theoretical high-temp det I'm afraid. High pressure blasts of liquids are actually used in bomb disposal because they disrupt IED components without triggering the explosives, they're called disruptors and are powered by substantially more energetic sources than a hot wire.

That's interesting about that high-temperature explosive though. They do all sorts of weird stuff in mining that I don't pretend to be super gripped-up on. I do note that the paper is only from 2012 and they make it clear they're talking about a product still in the research phase, so I wouldn't pin too much expectation on it.

[RuBisCO]

?? read again please. When I said how much easy is to reach orbit each year, I meant the cost due to technologies or just for practice in the matter. It has nothing to do with launch windows. But now you mention, that also reflects into the cost some how.

Well frankly it not easy to make sense of what you say.

Really? in what year? 1960 comming back from the moon to super speed?

Well never mind, lets said that is like you said. If 15% is what do you need to earth, then for the same speed you need almost the half of that in venus.

And now we have a lot of better materials, and like I said, it depends also of the design and density.

You have inflatable heat shields, does decrease a lot your density by unit of area. Also the same inflatable heat shield can work like ballon once you are at 50km height.

All flippant assumptions. Again for an asteroid mission there are no need for a heat shield, no need to aerocapture to save delta-v, no need for exotic heat resistant materials, heat shields or inflatable shields or ships that can withstand high gees or aerodynamic friction. Those things all add weight.

Lol, you think those rovers are just a draw??? You think that Geoffrey Landis and its team are just a regular internet guys?

Yes, those are just drawings, no I did not say "Geoffrey Landis and its team are just a regular internet guys" there paper is a “paper study†that is what I said. It is not a proposal, there is no designed rover, no built rover, all he present is a handful of experimental parts which provide some proof of concept. All of this is a very long ways way from machines on Venus's surface mining tons of ore, processing that ore and extracting vital elements out, all the while working in 500 C at 92 atmosphere, with sulfates mind you. All of which will weigh a heck of a lot more then a scientific rover.

It works in the NIAC, high advance nasa concepts. Read his curriculum, He design many rovers or different aplications that was used in many of the nasa missions.

Again with the appeal to authority. Sure he has designed rovers for NASA, but he has not built or designed a rover for Venus, all he presented there is that it is possible. I don't deny that it is possible, I'm just saying it is Impractical to scale that up to a fully automated mining industry on the surface of Venus! And that even if such an industry was built it would be heavy and expensive, more so then an Asteriod mining industry. So far all you have done is provide strawmen, red herring and other fallacies like the one above to avoid acknowledging this fact.

AND PLEASE STOP WITH THE PRESSURE ISSUE!! IS NOT AN ISSUE!!!

No it is an issue, denying it without premise does not make it so. Many components that work here on earth do so under earth pressure of less. Take a capacitor for example, at 92 atmosphere the insulators between the plates will be crushed and the cap won't work like it does. At 92 atmosphere the arcing from a rotor to a stator in a motor could happen, any kind of conventional bearing or seal will be shot, etc, etc. These are not impossible to solve problems, they are just expensive to solve and add weight.

Yes..!! Humans can die with that pressure, The max is 33 bar, but if you overseed that you die for chemicals reasons, no due to pressure.

For example Cachalot are mammals like us, this is mean they had air inside its lungs (pressure problem if you change from high pressure to light pressure quick or vice versa.), but nonetheless, they can immerse to 3km of deep (250Bar) for search food. And their limits is not becouse pressure, Is becouse they can hold their breath 90min.

Are you suggesting human should work on the surface of Venus? Actually at extreme pressure proteins fold differently, it requires some evolution to adapt to life at extreme pressures or be able to operate at those depths, in short: human's are not spermwhales.

You think that all asteroids form from dust? Asteroids were parts of stars or other planets, they have metals portions more dense than we can find at earth.

No I don't think or have said they are from dust, only that C-type asteroids are primordial, and have all the elements, including the most popular, hydrogen, oxygen, carbon, iron, aluminum, in large quantities. Some asteroids like the M-types were in fact part of the cores of failed planets, those ones a could provide a lot of rare earth minerals in concentrations not see on earth (because our core is not exposed), but for a singular colony a C-type asteroid would provide everything they need materially. A M-type asteroid is for a secondary mine for getting the really valuable stuff in bulk and for potential profit on earth.

Do you like to read about asteroid mining, but you never read how difficult it is. What are the problems that you need to deal.

First, anything that we know about mining at earth or different methods, etc. Do not work in space.

I've explained how to mine an asteroid, and no it not like mining on earth.

Second a simple drill, if you dont fix your tool to your asteroid (this is mean extra holes that you need to do), the only one that will turn it will be you, or your spacestation.

I've explained how to do this already: a boring mining or 'mechanical worm' can eat out an asteroid from the inside. It remains fixed to the walls of the tunnels it bores. Such a machine would not need to be the size of terrestrial tunnel borers, as its tunnels are not designed for functional purpose (like trains), instead it can be small, like a meter across at most. The boring head would go through C-Type asteroid material at 1.3 g/ml like butter!

Third, you need always something to push against. That is super easy in a planet with gravity (that is becouse all transports vehicles are 10000 more efficient than any space vehicle). How you move all the material that you extract?

Inside the mining tunnels the machine would push against the walls and climb back out, bring with it crushed rock to a station on the surface. The mode of locamotion would be the same as a worm (hence the name) like this:

1. Expand section A

2. Deflat section B

3. Extend piston connecting section A to section B

4. Expand Section B

5. Deflat Section A

6. Retract piston connecting section A to section B

The 'inflated' sections of the 'worm' hold it firm against the walls of the tunnel. They don't need to be inflatable badder, they could just be hydraulic walls just like the boring machines here on earth.

How you keep all material in one place without float around and lost it?

The material is mechanically compressed into a chambers that makes up segments of the mechanical worm. Once full it crawls back to the station on the surface. In the station it “excretes†what it has collected into the stations enclosed containers. If you don't believe such a system can work then stand on your head and drink, you will find that your throat is preforming what you would call a miracle.

You can not su.ck them because there is not air. You can not use a simple conveyor belt becouse you dont have gravity.

The boring head is pressed against the rock, as it spins, crushed rock is forced through holes in the crushing face, mechanical pressure pushed it back into the storage segments, Piston walls in the segments allow it to excrete its contents later. After that material can be compressed into bricks which can be grabbed and move about robotically.

There is ways to solve these problems, but you always need to deal with the fact that you dont have something to push against.

Again you have the walls to push against, like this: http://www.youtube.com/watch?v=IB19qOzX-qY except not as cute and with no gravity to fight against.

So? they still have a product which has not competitors in what it does. One advice, always tries to delegate any economic decision.

No they have th compete against heavy lift helicopters and aircraft, sure those consume more fuel but they have entrenched industries and require a fraction of the storage costs. Pratical things like that.

I am not talking about very rare elements, I am talking about elements that you may need in big amounts and you do not have enoght. Maybe carbon, calcium, magneso, sulfure, lithium, potacium, argon, xenon, sulfur, phosphorus, sodium, etc.

All plentiful in C-type asteroids in concentrations as high concentrations. Even argon and xenon can be found though they would most likely be imbedded into the surface layers of an asteriod via solar winds

Besides, a C type asteroid "may" be compound of many elements, but in any place it said that has all. No even in small amounts.

Again any rock contains ALL the natural elements, it just some of them will be concentrations of parts per trillion. The C-Type asteroids on the other hand being undifferentiated matter contain all the natural elements in higher concentrations then that.

Is like in the planets, if you mine one place you will find that you have a lot of some components and almost nothing of others.

Actually this is what C-Type, S-Type and M-Type asteroids do as well, as they are formed differently and have different elemental compositions. The C-Types contain volatilities, common elements as well heavy metals, while the M-type are concentrated metals.

The same happen with asteroids becouse they form in a similar way. Meanwhile at venus you can search in other place, in your space mining station you need to go and search another asteroid, or wait to be sent from the earth (9,5km/s just leo).

Movement from one asteroid to another may not be much delta-v if they are both NEOs. And again one C-Type asteroid can provide all the necessary elements. So there is no need to move around.

I am not saying that asteroid mining has no benefics or profits. I never said that. But asteroid mining does not solve all earth problems.

But I'm not saying asteriod minign solves all earth problems, I only saying it more pratical than Venus mining.

In the same way than an airplane can not solve all transport problems. You got that?

A venus mine is not a heavy lift zeppelin for a rare and specific task, it has not use what so ever.

?? So why I mention the mechanical windmill? It was not for electrical purpose. It was to produce work. This work would cold the water so the cycle can continue.

...WHY??? Ok let me get his straight you boil water for something, you then compress it back into water... why? What need is there for boiled water at the surface of venus? Why not just use the mechanical work of the windmill directly and avoid all the energy transformation cycles?

I put that in hold, I will do the math to compare both cases. Then I tell you.

Sure.

What adding cost? the same propulsion system that you can use to move a massive object, it will be the same than shot all that water in the right direction.

With this approach you only move the water, not the whole planets with its core, grounds, etc. How much % of water has europa or pluton?

You gave me a figure of 80%, so I told you the answer is a saving in weight moved is 20%. Now sure if you minning a body that is only 20% water that might be best, but how do you move that much water?

The surfuce yes.. But here you need to take the atmosphere. After the moon formation, is estimated that earth took 10 millons years to cold down.

This is becouse most of its gas and water remains covering all earth with clouds, so then you need to take into account the temperature of clouds like surfuce at high altitude, this is mean low temperatures at high altitude but really high temperatures in the surfuce.

Again the impacting body will not be delivering as much energy as what created the moon which weighed several or orders of magnitude greater (I theory suggest it was mars sized) Second was the early earth covered in the shadow of a sunshade devoid of solar flux?

You are wrong, these ideas are about terraforming venus. We are rising its ground lv to heights with more habitable conditions.

After that we can start to convert the co2 of direct way without use water. But is less efficient than use a replicator like plants.

Your changing the meaning of the word: building floating cities is not “terraformingâ€Â.

i dont care :S, And you have a psicologic issue if you interpret all my words this way.

When I mention education problems, you start to talk about poor countries and discrimination.

Now I said fusion with the ambient and you talk about kill 99% of the populate.

I will not even bother to explain this.

Hey if your going to give me generic and vague statements like “fusion with the ambient†I'll interpret it any way I want.

[RuBisCO]

Anyways back to Terraforming Venus

So I did some spread sheet caculations on moving large comets and plantiods.

There are two realistic means of proplusion we can consider: somekind of fusion engine or high powered fission engines like the nuclear salt water rocket. The fusion engine we can assume can opperate off the comet completely for fuel, both as propellant and for fusionable hydrogen, deuterium, boron, etc, assuming we ever develop a means of sustaining such fusion. I give this a thrust to weight ratio of 0.001. The nuclear salt water rocket from zubrin paper has a thrust to weight of 40, the only problems is it will need to bring all its uranium or thorium with it (and breed the uranium from the thorium) while the rest of the propellent can come from the comet.. oh and technoloigically building a rocket that can contain a continuous nuclear explosion is... questionable.

So lets get to the numbers:

4000 AU in the oort cloud a 1*10^18 kg comet (~120 km wide) has an orbital velocity of just 471 m/s. To cancel all that out would require 15,000 kg per second of fuel at an Isp 4000, 588 MN of thrust at 14.4 TW, for 305 years. 60 million tons of fusion propulsion plant and equipment would be needed, or just 1500 tons of fission propulsion equipment plus 1.5 million tons of Uranium (assuming 90% efficiency). 0.01% of the comets mass would need to be consumed as propellant. It would take 45,200 years to fall to venus. It would require the same amount of power and propulsion for a 1*10^16 comet (about ~25 km wide) in the kepler belt at 40 AU and 4710 m/s delta-v needed, except 1% of the comets mass would be consumed as propellant, it would take ~45 years to fall to venus. The maneuver is not instantaneous (obviously) so there will be no Oberth effect (except for the oort cloud body) and the cost in delta-v would thus increase, maybe even double but it may also be possible to fly past one of the gas giants for a gravity swing.

At Pluto space/Keplar belt of 40 AU, a 1*10^18 kg comet has an orbital speed of 4710 m/s, It would require 1.5 million kg per second of propellant at an ISP of 4000 for 305 years, 58.8 GN of thrust at 1442 TW to cancel out that velocity in 305 years. 6 billion tons of fusion tug, or 150,000 tons of fission tug, plus 150 million tons of uranium/thorium.

Clearly the Fission "tug" is the lighter option, it is just we need to extract millions of tons of uranium or thorium and ship it up there.

Now it would take 1400 of the 10^18 kg comets to eqaul the mass of water on earth (assuming they are 100% water) I would say a full 10,000 of them to blast away venus's atmosphere, give it spin and add enough hydrogenated and carbon seqestering materials to completely soak up all the CO2. For the 10^16 kg comets we would need a million of those.

Once a "tug" moves a comet in for collision, it can detach in the final days, fly by venus and back out to kepler space to get another comet, minimal delta-v need be spent, but we are talking roughly 500 years per cycle, so to get if we built 500 of these things it would take them 10,000 years to move all the comets.

If we use the fission engine option it would require at least 1.5*10^15 kg of uranium/thorium, but that is 0.0066% the mass of the largest M-type asteriod (16 Psyche) so if just that one asteriod has a uranium/thorium concentration of 66 ppm (about 5-10 times earth's crust concentration) we are good to go, we would just need to process all 2.27*10^19 kg of Psyche to get it all. The fusion tug option would forgo this, but instead each one of those tugs alone is a gigantic asteriod size ship! Added together and assuming 20 reuses they weigh 2 times as much as the fission ships and all their uranium/thorium fuel. The only diffrence is the fusion ships would be made out of much more common stuff, aluminium, copper, steel, carbon composite, etc, use "all" the parts of an asteriods. I guess both options could be done at once, keep building fusion tugs while collecting enough uranium for the much lighter fission tugs. Imagine a 100,000 ton standardize fusion tug produce via produce and operated automatically, it would require 60,000 of these to move a 10^18 kg comet to venus and back out to another comet in under 500 years, we would need 300,000,000 of these ships to do it all in 10,000 years, add in all the supporting infrastucture to keep these ships tuned up and operating for 10,000 years of operation.

Perhaps a better option will come about, cheap antimater, gravity and anti-gravity drives, wormholes, etc, but yes it could be done within less fantastic technological limits, it just would require a massive solar system wide economy in which the largest of asteriods and in which hundred of millions if not a billion ships can built and kept operating for at least 10,000 years.

Edited February 25, 2014 by RuBisCO
Correction on free fall times!

[Rakaydos]

If there's no rush, using a solar sail to deorbit an oort cloud object would probably be more efficent. Instead of heavy nuclear material, you're shipping miles upon miles of reflective material, and letting it sit there.

[RuBisCO]

If there's no rush, using a solar sail to deorbit an oort cloud object would probably be more efficent. Instead of heavy nuclear material, you're shipping miles upon miles of reflective material, and letting it sit there.

Yeah but that would take trillions of years, longer then the lifespan of the sun, a solar sail with say a newtron of thrust (which out in oort cloud space would be a huge stail measuring hundred of kilometers wide) would take 17.4 trillion years to de-orbit a 10^18 kg comet.

----

Anyways another option is to mine hydrogen from comets. Hydrogen would reduce the amount of water needed on venus, plus soak up all of venus CO2 by converting it to water (and solid carbon). Hydrogen could be mined from the gas giants but that would require crawling to the bottom of the gas giants gravity well and stripping atmosphere off the top (will countering for drag) then crawling out of the gas giants gravity well. The energy required to convert 1 kilogram of hydrogen from water is roughly 200 MJ (assuming 70-80% efficency) that the same amont of energy needed to move 1 kg of material to 6.3 km/s, So if mining a comet direcly saves you more then 6.3 km/s in delta-v it might be worth it. Of course we also needed to add the mass of melting equipment, electrolysis equipment, fusionable extractors for making fuel for the fusion reactors, cryogenics plants to cool the hydrogen down to a liquid and massive fuel tanks to move the hydrogen. We can use the waste liquid oxgyen as propellant though, though it would provide worse ISP then water. Assuming we don't blow away venus's atmosphere we would need 4.2*10^19 kg of hydrogen to convert all of venus's atmosphere or about 400-500 10^18 kg comets would need to be completely coverted (assuming they are 10% hydrogen by mass, nearly completely water-methane-ammonia, 800-1000 if they are 5% hydrogen). Still 97% of the mass moved to venus would need to be water, not hydrogen (assuming there are negliable level of oxides on the surface of venus) and that would be at least 1.4*10^21 kg of water. The numbers I provided assume 10^22 kg of material smashed into venus which provides plenty of overhead, if we were to mine water directly and deliver it directly it could save some mass, but that depends on how much water a comet is made out of, if it 80% water is it worthwhile to melt and extract all the water? Probably not.

Edited February 25, 2014 by RuBisCO

[Pds314]

Hmm... I think I'd put an array of mirror-sats that were transparent to IR but reflected visible light away from the planet.

Then, once the temperature was suitable, figure out a way to sequester 250 billion megatonnes of CO2..... Not sure how that is gonna work. Sending it to interplanetary space would take too much energy (1.25E28 joules or so).

For oxygen, just find an asteroid with large quantities of Iron or Silicon and burn it in the O2.

[Pds314]

Just send Earth's moon into an intercept with Venus and boom. No more atmosphere.