Nasa is considering a Manned Mission to Venus before Mars!

[Bill Phil]

Hydrogen can react with CO2. And just about anything. Helium is more rare in general, so using it could be a bit more expensive than gaseous hydrogen.

[AngelLestat]

My knowledge about chemistry is low. So can you point me how a hydrogen blimp will be in danger in the Venus atmosphere? What conditions are needed to the reaction? How strong it will be?

[Sean Mirrsen]

My knowledge about chemistry is low. So can you point me how a hydrogen blimp will be in danger in the Venus atmosphere? What conditions are needed to the reaction? How strong it will be?

A hydrogen blimp in Venus atmosphere would mostly be a terrible way to store hydrogen. At the pressure and gravity that exists at that altitude, the colony could be held aloft by oxygen and nitrogen even.

More to the point though, I can't say that a hydrogen blimp would be exactly in danger in the Venus atmosphere, but hydrogen would still gradually seep out, it's the best gas for escaping containment, so it's best stored cooled and in thick tanks, not in blimps under the blazing sun. Hydrogen does react with CO₂, but the reaction requires significantly more heat than would be present at that altitude, and any gas that seeps out would be immediately swept away by wind. Plus the products of the reaction are methane and water, there is still no oxygen for anything to burn unless hydrogen seeps into the living quarters, even if something is struck by a freak lightning.

Basically, the biggest points against having a hydrogen blimp on Venus is that hydrogen is one of the irreplaceable commodities that need to be shipped in. Any benefits it has are dwarfed by the fact that hydrogen is both rocket fuel, a source of water, and CO₂ scrubber material - the less of it lost to seepage, the better, and the blimps can fly on something that's in less demand and is easier to contain.

[Rakaydos]

On the other hand, most of the applications where hydrogen leakage is a worry involves a high pressure differential. How much hydrogen leakage would you expect in an equal-pressure system such as a dirigable? Hydrogen blimps were used in war...

If planning a long term mission, it might be better to send new dirigables with hydrogen, and replace the hydrogen with heavier oxygen on site, using the displaced hydrogen as feedstock for various useful reactions in venus's atmo.

[AngelLestat]

A hydrogen blimp in Venus atmosphere would mostly be a terrible way to store hydrogen. At the pressure and gravity that exists at that altitude, the colony could be held aloft by oxygen and nitrogen even.

A colony may had benefics using oxygen and nitrogen (until certain point, the colony needs to be aerodynamic enoght to avoid end in the poles, it needs a constant speed of 2 or 4m/s), but we are talking of this mission.

Who cares if you spent hydrogen.. There are plenty here at earth, there is plenty there too. Of course it may be more valueable use it for other stuffs if you have a lot of colonies there.

The mission concept use helium, more difficult to stop than hydrogen, because its molecule has a single atom.

And with my idea, you just compress the hydrogen you need, which may help to vary buoyancy. Also helps saving weight and increasing energy storage at nights.

so it's best stored cooled and in thick tanks, not in blimps under the blazing sun.

As rakaydos said, you have almost equal pressure.

Also there is ways to avoid hydrogen leaks, one is using reduced graphene oxide.

These are also some of the advantages that graphene can provide to the Fuel Cells:

http://www.understandingnano.com/fuel-cells.html

I use 60% which is today normal efficiency for PEM fuel Cells , but in 5 or 7 years may reach 75%, one step closer to their 85% theoretical limit.

If planning a long term mission, it might be better to send new dirigables with hydrogen, and replace the hydrogen with heavier oxygen on site, using the displaced hydrogen as feedstock for various useful reactions in venus's atmo.

Yeah, that might be one which is easier to do.

I was thinking in a first unmanned mission to have all the missing data needed to plan this mission in the most efficient way.

Then you sent a second and maybe a thid unmanned mission with a similar system that I show, but with the possibility to harvester sulfuric acid and extract the hydrogen and oxygen.

So when the manned mission arrives (with the fuel needed to just go back from venus low orbit to earth), then can enter in the atmosphere (without fuel) and take it from one of the 2 unmanned harvesters.

Of course it means docking in atmosphere.

Case: It's not possible.

Cooper: No. It's necessary.

The manned blimp will be also equipped to produce fuel situ in case something happens with the 2 first harvesters.

Then explore venus not for 1 month, 12 or 14 months. So you have a travel time back to earth of 3 months instead 300 days as is planned.

Yeah I found the complete PDF from this concept study.

It seems they also thought about ISRU and docking in atmosphere, but they said that might be a bit risky to be try it in the first mission.

http://es.scribd.com/doc/250698199/HAVOC-Final-Outbrief-General-pdf

So someone has an idea of how achieve a safe docking in the atmosphere? What kind of mechanism and procedure you will use it?

Edited January 6, 2015 by AngelLestat

[Sean Mirrsen]

While I technically agree with a lot the above, this:

Who cares if you spent hydrogen.. There are plenty here at earth, there is plenty there too.

Is very much not true. Hydrogen and other light gases have been eroded from Venus's atmosphere by solar wind due to its lack of a proper magnetic field. Hydrogen is present there in very low amounts, mostly as water vapor. I rather doubt that it can be collected in sufficient amounts to offset the loss to seepage.

So someone has an idea of how achieve a safe docking in the atmosphere? What kind of mechanism and procedure you will use it?

I'm guessing it will basically amount to the gondola having a rigid dockable extension protruding slightly past the dimensions of the balloon, thus allowing the gondolas themselves to dock together and form an airtight passageway. Probably at least two simple rigid beam connectors would be good as well, to prevent sway. Beyond that, I don't know. If the design of the blimp is limited to "gondola suspended under inflatable body, then the options are fairly limited.

Outside of that, best way would be to integrate the living space into the middle of the inflatable body, so that the "docking ports" such as they are can be on the sides of the balloons. I lack the technical knowledge to provide verisimilitude beyond that.

[Impaler]

AngelLestat: Thx for the PDF, I had been wondering if their was one for this mission.

I like your Hydrogen blimp concept as you have made it serve double duty as an energy storage mechanism, if it were just for marginal buoyancy over Helium it would not be worth the difficulty but by replacing batteries the savings in mass can be considerable and the ship will have good nigh-time power. Leakage of Hydrogen during the cloud-level portion of the mission dose not look to be much of a concern, the duration is just too short and if more lifting gas were needed then a secondary Nitrogen balloon can be inflated inside the blimp to supplement it, it is common for blimps today to have secondary interior balloons of denser gass at the for and aft to control trim and N2 balloons could serve this purpose. What kind of total energy storage would you get under your proposals, and how much mass is saved vs assumption of best-of-breed Lithium Ion battery storage? One nitpick, get rid of AC/DC inverter and just use DC motor for propeller, lower mass by a lot.

The transport of Hydrogen during the trip to Venus would be the primary problem, but again this is a challenge that a Mars mission is generally believed to have as well. Though in the Mars case I believe that extracting moisture from the Mars atmosphere will prove to be superior to stored hydrogen brought from Earth. Like-wise the collection of the SulfuricAcid droplets on Venus will be more practical then transporting it from Earth, but this is not viable for the initial inflation of a blimp, the Hydrogen must be on board the ship at the time it makes atmospheric entry.

From numbers I found the peak density of Acid droplets is a 45 km altitude, a mere 7-10 km below the operational altitude and within the tensile and thermal capability of things like a Zylon cable the density is 25 mt per Million m^3 of atmosphere (note that this is 5% of the density of an Earthly cloud). If this atmosphere is drawn in at a rate of just 1 m^3 a second (a very low rate) then the droplets are condensed out by passing the atmosphere through a fine screen (of gold so no it will not be destroyed by the acid, for that matter plate everything in gold, it's ridiculously cheap and easy to do) then over 2 mt of acid would be collected a day. The acid mix is thought to be 25% water, we might simply separate that out and dump the acid, or if it were deemed worth the effort water extraction could be raised to ~40% of gross droplet weight by chemically converting the acids hydrogen content.

So water availability on Venus seems to be no problem when one actually looks at the numbers that are relevant (cloud density not overall atmospheric density). I would imagine that a specialized blimp-ship for doing this would be developed a 'cloud trawler' vessel that would dangle the collector unit on the end of a tether with the vessel equipped with radar to find and navigating around searching for the thickest clouds to optimize collection rates. The acid mix would be stored in the collector and perhaps once ever day or two the collector is hauled up and the acid transferred to a tank in the blimp gondola. When the Trawler itself is full, in perhaps a week or two it dose a fairly standard mid-air-refueling style transfer to another vessel (it extends a hose with a cone, other vessel inserts a probe), with the other vessel housing the equipment to process or use the water or acid mixture.

[Voyager55]

Would be kind of cool to say "I'm flying a blimp over Venus" yet it's a pretty pointless mission. And way to many things can go wrong. Like being simultaneously squashed and fried alive if your blimp fails. ..............Stick to the moon and Mars for now NASA.

[NERVAfan]

Basically, the biggest points against having a hydrogen blimp on Venus is that hydrogen is one of the irreplaceable commodities that need to be shipped in. Any benefits it has are dwarfed by the fact that hydrogen is both rocket fuel, a source of water, and CO₂ scrubber material - the less of it lost to seepage, the better, and the blimps can fly on something that's in less demand and is easier to contain.

Sulfuric acid contains hydrogen, so you could get it from the clouds.

EDIT: I'd imagine you'd want to use a rocket fuel you could make on-site, to minimize the mass, likely some kind of hydrocarbon that could be made biologically from Venus's clouds/atmosphere.

[AngelLestat]

Ok, here it is the HAVOC PDF ready to download and easy to see (I will post it in the first page too)

https://www.dropbox.com/s/y5gu06h0u7n7v66/HAVOC-Final-Outbrief-General-pdf.pdf?dl=0

While I technically agree with a lot the above, this:

Is very much not true. Hydrogen and other light gases have been eroded from Venus's atmosphere by solar wind due to its lack of a proper magnetic field. Hydrogen is present there in very low amounts, mostly as water vapor. I rather doubt that it can be collected in sufficient amounts to offset the loss to seepage.

The lack of hydrogen is the biggest problem of Venus in my opinion. This does not mean that we can not do ISRU, it only means that it would not be so energy/efficient as might be in different moons/planets. (In mars or the moon, is not so easy either, far from the poles the water is too stuck in dirt and if you try to heat it would sublime into vapor without liquid phase)

Scientist already believe that venus is in equilibrium with respect to hydrogen lost by atmosphere erossion which is compensate due constant asteroids and matter that falls to the planet.

About the amount of water is 15000 km3, almost the same that earth atmosphere, with the difference that it is 90 times thicker.

Another option is to make fuel using the CO2, that is the main objective in mars ISRU, but in venus it would be much easier due presssure.

I'm guessing it will basically amount to the gondola having a rigid dockable extension protruding slightly past the dimensions of the balloon, thus allowing the gondolas themselves to dock together and form an airtight passageway. Probably at least two simple rigid beam connectors would be good as well, to prevent sway. Beyond that, I don't know. If the design of the blimp is limited to "gondola suspended under inflatable body, then the options are fairly limited.

Outside of that, best way would be to integrate the living space into the middle of the inflatable body, so that the "docking ports" such as they are can be on the sides of the balloons. I lack the technical knowledge to provide verisimilitude beyond that.

Yeah that might work, maybe with a damping mechanism against any possible turbulance.

It can be a tunnel to the gondola inside the envelope using the same blimp material in case envelope docking prove to be safer.

But the main reason to "dock" is to get the fuel harvested by the drone. So maybe a hose (like the one use it to refuel airplanes in air) may work. In case of emergency that we need extract another equipment from the drone, we may have a more risky """docking""" procedure to that case.

What kind of total energy storage would you get under your proposals, and how much mass is saved vs assumption of best-of-breed Lithium Ion battery storage? One nitpick, get rid of AC/DC inverter and just use DC motor for propeller, lower mass by a lot.

The weight-energy density of batteries is about 1/20 that of gasoline and about 1/10 that of hydrogen (because small pressurized tanks have a bad weight-volume ratio), But the true is if we have a big hydrogen tank, then we would have much more energy density than gasoline.

Hydrogen (compressed) 142 MJ/kg

Gasoil/Diesel/gasoline close to 47 MJ/kg

Lithium-ion battery less than 1 MJ/kg

I dint did the right calculations yet because I am not sure to understand the KWe unit used in the PDF. That is an "USA unit" not very common used in the rest of the world. I guess is almost the same that KVA for mostly all cases. But not sure yet.

About the inverter, I also thought about that. But there are many Pros with AC engines against DC when we are talking of big powers.

Take the electric cars example, it does not matter if they use just batteries or fuel cell, they always use a AC motor. The same for electric airplanes, etc.

Lost in efficiency plus weight of the inverter is not enoght to counter the cons of DC motors (also more dangerous).

Like-wise the collection of the SulfuricAcid droplets on Venus will be more practical then transporting it from Earth, but this is not viable for the initial inflation of a blimp, the Hydrogen must be on board the ship at the time it makes atmospheric entry.

Yes but if we compare the mass of hydrogen that we need to inflate the blimp vs the LOH mass to launch, then we have 6000kg Vs 60000kg. 60 to 1. So if we can carry only the hydrogen to inflate the blimp, we would have a 5 to 10 times cheaper mission (counting the extra drones blimps that you need to sent to harvester the fuel)

From numbers I found the peak density of Acid droplets is a 45 km altitude, a mere 7-10 km below the operational altitude and within the tensile and thermal capability of things like a Zylon cable the density is 25 mt per Million m^3 of atmosphere (note that this is 5% of the density of an Earthly cloud). If this atmosphere is drawn in at a rate of just 1 m^3 a second (a very low rate) then the droplets are condensed out by passing the atmosphere through a fine screen (of gold so no it will not be destroyed by the acid, for that matter plate everything in gold, it's ridiculously cheap and easy to do) then over 2 mt of acid would be collected a day. The acid mix is thought to be 25% water, we might simply separate that out and dump the acid, or if it were deemed worth the effort water extraction could be raised to ~40% of gross droplet weight by chemically converting the acids hydrogen content.

Tantalum is better than gold and I guess cheaper to deal with acid in big concentrations and high temperatures.

About your calculations... 2mt? What is 2mt? 2 metric tons?

It can not be that number..

The acid mix would be stored in the collector and perhaps once ever day or two the collector is hauled up and the acid transferred to a tank in the blimp gondola. When the Trawler itself is full, in perhaps a week or two it dose a fairly standard mid-air-refueling style transfer to another vessel (it extends a hose with a cone, other vessel inserts a probe), with the other vessel housing the equipment to process or use the water or acid mixture.

Yeah, I dont think that acid collecting would be so hard to do in the venus clouds, less for the low requirements of the mission, you also dont have limit of time to do it, you can harvester that in 1 year, that is enoght time no matter how difficult would be. But if we think into future with many colonies there. It will be hard to become economically self sustainable if you dont have easy access to water (which you need not just to survive, to produce any kind of product too)

Maybe if there is a way to mine asteroids on LVO and "lowering the water somehow" to the colonies, then yes. I guess Venus has a great future over any other place.

Would be kind of cool to say "I'm flying a blimp over Venus" yet it's a pretty pointless mission. And way to many things can go wrong. Like being simultaneously squashed and fried alive if your blimp fails. ..............Stick to the moon and Mars for now NASA.

more things can go wrong in mars than venus. Also if we achieve to improve our climate models here at earth thanks to venus, then any accomplish that we might have in mars would not be so great and useful compared to this.

Sulfuric acid contains hydrogen, so you could get it from the clouds.

EDIT: I'd imagine you'd want to use a rocket fuel you could make on-site, to minimize the mass, likely some kind of hydrocarbon that could be made biologically from Venus's clouds/atmosphere.

Yeah, carbon is the best material, but that will be possible only with big colonies already there. You can 3d print small stuffs, but make a whole rocket.. sure not.

[Rakaydos]

So it sounds like we've got this awesome plan for ISRU. Great. What do we need to make it work?

Someone mentioned 10-20 km of acid-resistant cable , with what amounts to an acid collecting bucket at the bottom. What kind of catalists, energy, and facilities are needed to crack acid into useful components, how do we separate them, how do we store them?

[Impaler]

Double checking my numbers the density of acid droplets in Venus clouds can't be as high as I had thought, that was probably the vapor density I was looking at, the numbers are hard to get but most of what I'm reading is saying the density of droplets is comparable to Earthly fog and around 0.1 grams/m^3 at the densest cloud layer. This would mean that Venus has more like 100 kg of droplets per million m^3. Still this is quite viable to harvest, just increase the air-intake rate, it may not even require a fan if your getting differential winds at altitude, a scoop with a 10 m^2 area will bring in a huge amount each day. Also the expected air-speed of the Blimp is expected to be in the range of 5 m/s so this would translate to 50 m^3/s going into a collector, which would produce around 430 kg a day.

[AngelLestat]

Ok, I made some calculations, and even if we extract only 120kg of sulfuric acid by day, we have enoght rocket fuel in just 1 year. And I really doubt that the manned mission may be ready so fast after the unmmaned.

Methods to get rocket fuel in situ:

1- We carry few kg of H2 from earth, we combine with the Venus CO2 to produce methane / LOx.

Sabatier reaction, CO2 + 4H2 → CH4 + 2H2O, Oxygen is liberated from the water by electrolysis, and the hydrogen recycled back into the Sabatier reaction.

2- LH2 / LOx from the sulfuric acid.

The sulfuric acid concentration vary from 60% to 85%, so we have 30% water already that is easy to get If we chill or heat, because sulfuric acid freezing point is 10c and boiling point is 350c, the heat option may be efficient if we use the external heat 75c and rise it 25c to vapor the water. We can also use electrolysis which would need very few power because h2so4 is already an electrolyte.

I am not sure what is the best (low energy requirement) method to get hydrogen and oxygen from H2SO4. Hard to find any info when the reverse reaction is so popular at earth.

Here are some links that explain a bit more about ISRU in Venus:

http://selenianboondocks.com/2013/11/venus-isru-what-do-we-have-to-work-with/comment-page-1/

http://selenianboondocks.com/2013/12/venus-isru-condenseables/

http://selenianboondocks.com/2013/12/venus-isru-isru-development-phases/

-------------------------------------------------------------

Lets remember the mission phases:

Phase 1: Robotic Exploration / Phase 2: 30-day Crew to Orbit / Phase 3: 30-day Crew to Atmosphere / Phase 4: 1-year Crew to Atmosphere / Phase 5: Permanent Human Presence

We know that they also considered ISRU but they discarded due "Atmospheric rendezvous is challenging for early missions" and "No abort options during rendezvous (cannot ascend to TEI stage)"

So the key factors to improve this mission would be:

a) Better energy management and storage to all exploration vehicles, this include the use of a KITE to counter the meridional winds, remplace helium by hydrogen, and remplace much of the battery weight with a fuel cell / electrolysis cycle.

Change the mission arquitecture to avoid carry the fuel needed to launch from the clouds doing ISRU and remplace the 300 days travel return by 100 days.

We can have "a" without "b", but not vice versa.

The new HAVOC architecture might be:

Phase 1: Robotic Exploration / Phase 2: Unmanned Vehicle with ISRU / Phase 3: 30-day Crew in Orbit / Phase 4: 1-year Crew to Atmosphere / Phase 5: Permanent Human Presence

Phase 1: Is a small robotic version of the manned vehicle but without the rocket. It will have fuel cell cycle and KITE (this also work to test the design)

Phase 2: A robotic normal size copy of the manned vehicle, this would do ISRU using the same rocket to storage the O2 and LH2/Methane.

Phase 3: 1 or 2 years later, humans arrive to venus with the transfer vehicle that already has enoght fuel to go back from venus orbit, in LEO is waiting a copy of the unmanned ISRU, after 1 month in orbit -->

Phase 4: the crew board the blimp and get down to the atmosphere. They proceed with Atmospheric Rendezvous, transfer fuel to their rocket, or in case of problems use the unmanned vehicle rocket. After that, the other vehicle continue ISRU (both can). They explore by 1 year, then rise again to LVO, board the transfer vehicle, and proceed with the 100 day return transfer to earth.

(during the rocket ascent to LEO, they can abort in case something happens, the capsule is ejected, a ballon would inflate, and they would wait for the unmanned blimp reach them to try again.)

Phase 5: They already had 2 unmmaned vehicles exploring (1 doing ISRU with a rocket ready) to help in the deployment of a permanent outpost.

Not sure how much cost reductions with get in this case. I am sure that it may be a better way to design these phases. Some ideas?

Edited January 9, 2015 by AngelLestat
Some corrections

[Dispatcher]

...Not sure how much cost reductions with get in this case. I am sure that it may be a better way to design these phases. Some ideas?

I think if you are really serious about this, a real science forum frequented by a higher percentage of real scientists would probably yield more results to your liking. In contrast to a ... let's face it ... a gaming forum. Otherwise, just take a wait and see approach and hope that more posts satisfy your questions.

[cryogen]

If Venus has 84% of the gravity of Earth, why is it practical for a SSTO to reach orbit from 52 kilometers on Venus? What's the delta-V requirement for that maneuver?

It's not an SSTO actually. From page 30 of the PDF, they design for a two-stage ascent rocket, fueled by RP-1/LOX. The mass cost is 63 tons to lift a 2.2 ton crew capsule, and is the majority of the mass on Venus (96 tons).

(The atmospheric habitat is only 5.1 tons. And most of the dirigible mass is (presumably) only there for lifting the ascent rocket. So it's really expensive. They want 10 SLS cargo launches (including some Block 2) to carry everything there).

[AngelLestat]

I think if you are really serious about this, a real science forum frequented by a higher percentage of real scientists would probably yield more results to your liking. In contrast to a ... let's face it ... a gaming forum. Otherwise, just take a wait and see approach and hope that more posts satisfy your questions.

So I enter to just talk about this? It seems very selfish. Besides the few other forums related to space or physsics that I know, have almost the same average of Professional, Engineers and Physicists than KSP.

There are capable people here, the problem is that not everyone has venus in the map yet.. That might change with the years.

By the moment I am not complaint, is very easy come out with original ideas on Venus devices when there is so few people in the world thinking about it.

In case I wanna discuss this with people related to the topic, I can contact to some of the guys/girls which work in this project.

In fact my idea is to improve and check some of the new concepts that we are talking about. If they appear consistent, I can make a PDF with the names involved and sent it to Langley. Maybe they can find something useful.. or not.

It's not an SSTO actually. From page 30 of the PDF, they design for a two-stage ascent rocket, fueled by RP-1/LOX. The mass cost is 63 tons to lift a 2.2 ton crew capsule, and is the majority of the mass on Venus (96 tons).

(The atmospheric habitat is only 5.1 tons. And most of the dirigible mass is (presumably) only there for lifting the ascent rocket. So it's really expensive. They want 10 SLS cargo launches (including some Block 2) to carry everything there).

But you are answering your self, if the payload sent it to venus are not bigger than 100 tons blimp with rocket + 50 or 100 tons transfer vehicle. So maximun 200 tons, and you said that we need 10 SLS?

The pictures that you see are 8 Falcon Heavy (which may be reusable by that time) and 2 SLS. And I guess they needed more for the space inside the farings than for the mass to LEO.

--------------------------------------------------------------

A better understanding of the kite propulsion in Venus and how to use the high wind gradient at the altitude of study.

Which is more than 50m/s in just 5 km

The kites may be very small, sailboats get good speeds despite water drag due boat and keel displacement.

The blimp almost has no drag compare to a boat. That is why they can reach 150 knots.

A 30 m2 kite, has a power of 1MW at 10m/s (at 2000 mts low dense atmosphere).

We know that the concept propeller has few KW of power.

One thing that I could not draw in these perspectives is the Kite flight pattern with sinusoidally shape, projected in 40 degress forwards our speed vector.

Similar to this:

http://s20.postimg.org/dfp44f81p/10_590x340.jpg

The mechanism of each kite depends on 2 very light engines (one for each rope) which work to guide the kite, the side-slip manuver, and to retract the kite.

The side-slip manuver just release 1 rope of the two, and the kite does not produce more drag or forces, this work in case you wanna retract without force the engines, or to avoid possible turbulances.

The kites also automatic release both cables when the force exceeds some standards (as a Reel from a fishing rod), in case this continue, the side-slip manuver and the retract the cable to lower altitude gradient.

Edited January 10, 2015 by AngelLestat

[Bill Phil]

An SLS block II delivers 100+ tons to LEO. Not to Venus, so it might well take 5 to 10 SLS launches.

[cryogen]

But you are answering your self, if the payload sent it to venus are not bigger than 100 tons blimp with rocket + 50 or 100 tons transfer vehicle. So maximun 200 tons, and you said that we need 10 SLS?

The pictures that you see are 8 Falcon Heavy (which may be reusable by that time) and 2 SLS. And I guess they needed more for the space inside the farings than for the mass to LEO.

You are right! The smaller ones are Falcon Heavy, not SLS. That adds up to about 8*50t + 2*130t = 560t in LEO.

[AngelLestat]

An SLS block II delivers 100+ tons to LEO. Not to Venus, so it might well take 5 to 10 SLS launches.

then you just need 40 to 50 extra tons to sent 100 tons to venus.

I still dont see that number of SLS.

You are right! The smaller ones are Falcon Heavy, not SLS. That adds up to about 8*50t + 2*130t = 560t in LEO.

As I said, maybe they need the fairing space more than the payload limit of each launcher.

You need to sent 150 or 200 tons to Venus, this is 250 or 300 tons to LEO.

Also we are working here to reduce that number to almost half, and at the same time improve the mission value.

Edited January 10, 2015 by AngelLestat

[whiterafter]

I think a blimp on Venus being compared to done and dusted lander on Mars is like comparing apples to oranges.

I doubt NASA could get the funding for an enormous Venus project either, I can already hear congress people complaining that we don't go to the surface and that all our billions towards Mars would be wasted.

[Dispatcher]

So I enter to just talk about this? It seems very selfish. Besides the few other forums related to space or physsics that I know, have almost the same average of Professional, Engineers and Physicists than KSP.

There are capable people here, the problem is that not everyone has venus in the map yet.. That might change with the years.

By the moment I am not complaint, is very easy come out with original ideas on Venus devices when there is so few people in the world thinking about it.

In case I wanna discuss this with people related to the topic, I can contact to some of the guys/girls which work in this project.

In fact my idea is to improve and check some of the new concepts that we are talking about. If they appear consistent, I can make a PDF with the names involved and sent it to Langley. Maybe they can find something useful.. or not. ...

Yes, I think we get the idea that you are THE Venus evangelist (more so than Mr. Landis it seems) and that the KSP forums are your think-tank, on this topic. I actually don't have a problem with this. I just think you'd be more successful at the other forums as you "conquer" Venus. Edit: Actually I've seen you post on a variety of topics (other OPs and your own). And its understandable as this thread seems close to your heart. /Edit.

As I've indicated earlier in this thread, I value the concept of learning and benefiting from preliminary steps or goals as we attempt to spread out into the rest of the solar system. I don't think most people will desire to "conquer" Venus (at least its skies) until the surface of Mars is reached by humans; or more likely a base established. But I don't stop there. I think the best step for establishing a permanent human presence on Mars is to do so at our own Moon first. I find it interesting though that humanity seems to have this drive to go to somewhere somewhat familiar to them; in this case the desert world of Mars. Yet we largely don't seem interested in living, working or playing on the less harsh Antarctic continent or on/ under our much easier to reach (relative to off-Earth) seas and oceans and large lakes. We'd probably learn a lot right "here" too.

All of that said, its a pity that the early science fiction writers were wrong about the Martian canals and the jungles of Venus. If those worlds had turned out to be habitable in that sense, we'd already have colonies, not just bases, at both of those worlds. The Internet as we know it (hmmm?) might already span three worlds.

Edited January 11, 2015 by Dispatcher

[AngelLestat]

Here some good dates to launch the manned mission according to our ISRU mission perspective:

--Earth------------Destination---------Destination----------Earth------------Stay---------Mission------Injection

Departure-----------Arrival------------Departure----------Return-----------Time--------Duration-----ÃŽâ€V(km/s)

Nov-10-2021-----Mar-02-2022-------Jun-25-2023------Sep-29-2023------1.31 yrs------1.88 yrs------3.99

Jun-09-2023------Oct-15-2023-------Jan-21-2025------Apr-27-2025------1.27 yrs------1.88 yrs------3.71

2021: E-V-Transfer= 112 days---V-E-Transfer= 96 days

2023: E-V-Transfer= 128-day----V-E-Transfer= 112 days

Roughly deltaV requirements:

ISP: 440 lh2-lox

Total mission mass to LEO: 135 Tons. I miss something?

ELO to Venus aerobraking: 3.6 km/s

2 Blimp-ISRU-Rockets (include food): 30 tons * 2 = 60 Tons + propellent/engine 27 tons = 90 tons at LEO

1 Transfer Vehicle (dry mass: 30Tons): Food-water 1.5 tons + propellent/engine 15 tons = 45 tons at LEO

VLO to Earth Aerobraking: 3.4 km/s

1 Transfer Vehicle (dry mass: 20 tons): Food-water 1 ton + propellent 9.5 tons = 30 tons.

Ok we still need to find a new design for the ISRU blimp.. It needs ample variable buoyancy while maintaining good aerodynamics and fit inside the farings. Not easy.

I know how to implement all the kite mechanism, ISRU systems and energy fuel cell managment cycle. But not so sure how to acomplish the new blimp design.

Tips and critics accepted.

I think a blimp on Venus being compared to done and dusted lander on Mars is like comparing apples to oranges.

I doubt NASA could get the funding for an enormous Venus project either, I can already hear congress people complaining that we don't go to the surface and that all our billions towards Mars would be wasted.

Why it would be wasted? Knowledge never is wasted.

All the money they put in mars mission research was of great help and it will be used for a mars mission or for this mission.

Tell me one thing that it will be waste it..

In case you said Orion? Orion is kinda a waste of money because it does not work for mars. In fact may work as transfer vehicle to venus (in case they dont want design something better for that purposee), but not for mars.

In the same mars documentary, they ask: Why we design orion if does not have any clear objective or location to be used. ANd the same people involve said: we dont have any idea!!

It was just a goberment trick to keep busy all mars lovers.

A venus mission may help to design and perform a mars mission in the short term.

Yes, I think we get the idea that you are THE Venus evangelist (more so than Mr. Landis it seems) and that the KSP forums are your think-tank, on this topic. I actually don't have a problem with this. I just think you'd be more successful at the other forums as you "conquer" Venus. Edit: Actually I've seen you post on a variety of topics (other OPs and your own). And its understandable as this thread seems close to your heart. /Edit.

You came with all kind of psychological reasoning to day

So venus evangelist... heh, Ok I take it.

But just allow me to point some difference with respect that distinction.

Evangelist is a word which source is religion, and often religion is synonymous of conservatives or opposed to change.

I am quite the opossite. I can show you plenty of reply post that I did in which after discuss over many pages, I realize due logic, or evidence than I am wrong, and it takes me just 1 minute recognize my mistake or embrace the new concept.

But is true, there are many things that I like from Venus; like airships, floating cities, sailboats (that is were the kite idea comes from), etc.

I don't think most people will desire to "conquer" Venus (at least its skies) until the surface of Mars is reached by humans; or more likely a base established. But I don't stop there. I think the best step for establishing a permanent human presence on Mars is to do so at our own Moon first. I find it interesting though that humanity seems to have this drive to go to somewhere somewhat familiar to them; in this case the desert world of Mars.

Aha.. But there is the question...

Humanity seems to looks mars as something familiar to them. But what they see?

Only an image..

Is only one sense from the five. What is this thing we call home? only the visual image of our world? Or the pressure that keep us alive, the confort temperature to which we are used, or that strong force which never left us since we born?

The sound, taste and smell which can not be the same in such mars pressure.

In venus we have an sky and clouds; we need to ignore all our others senses to feel us like in home?

Yet we largely don't seem interested in living, working or playing on the less harsh Antarctic continent or on/ under our much easier to reach (relative to off-Earth) seas and oceans and large lakes. We'd probably learn a lot right "here" too.

But I guess is not a question about if we can find another place to live or build our home...

Yes we have plenty of space here at earth, but the resources are limited.

Also all those virgin habitats are taken by other species. What is their place if we keep expanding in this world?

All of that said, its a pity that the early science fiction writers were wrong about the Martian canals and the jungles of Venus. If those worlds had turned out to be habitable in that sense, we'd already have colonies, not just bases, at both of those worlds. The Internet as we know it (hmmm?) might already span three worlds.

For sure.

Also let me add that I read "many years ago" the Kim Stanley´s trilogy about mars, just to mention that I was quite into mars before read the Landis paper.

Edited January 12, 2015 by AngelLestat

[Impaler]

The usage of kites to counter the relative poleward and equatorial winds on Venus sound interesting, but I'm concerned that these kites would be delicate, likely to tangle in the wind or with each other and would be impossible to untangle. Would not simply lowering a static parachute into deeper air with lower relative wind speed be an adequate 'air anchor' without relying on complex active control. A drawstring on the chute should allow it to be expanded and collapsed for differing the amount of drag produced as well as allow it to be fully reeled back into the craft if needed.

The low density of H2/O2 propellent makes rockets very puffy and increases atmospheric drag, on Earth for launching from the ground they often end up being no better then hydrocarbon rockets. Add in the extreme cooling requirements for the Hydrogen which we basically can't even do on Earth (the hydrogen is allowed to boil inside the rocket on the pad) and I think that propellent choice is out. The traditional Methane/LoX combo from Mars would just optimal for Venus as well. As ISPP is considered a must have for human landings on Mars I think it is perfectly valid to incorporate the same technology on Venus.

[Rakaydos]

The usage of kites to counter the relative poleward and equatorial winds on Venus sound interesting, but I'm concerned that these kites would be delicate, likely to tangle in the wind or with each other and would be impossible to untangle. Would not simply lowering a static parachute into deeper air with lower relative wind speed be an adequate 'air anchor' without relying on complex active control. A drawstring on the chute should allow it to be expanded and collapsed for differing the amount of drag produced as well as allow it to be fully reeled back into the craft if needed.

The low density of H2/O2 propellent makes rockets very puffy and increases atmospheric drag, on Earth for launching from the ground they often end up being no better then hydrocarbon rockets. Add in the extreme cooling requirements for the Hydrogen which we basically can't even do on Earth (the hydrogen is allowed to boil inside the rocket on the pad) and I think that propellent choice is out. The traditional Methane/LoX combo from Mars would just optimal for Venus as well. As ISPP is considered a must have for human landings on Mars I think it is perfectly valid to incorporate the same technology on Venus.

can we merge the "airbreak" and the Acid Bucket into a single application? Or is there enviromental or multitasking issues with that idea?

Given the energy we have available, what kind of catalists and reactions would we need to create methane+LoX out of sulpheric acid and Co2?

[Impaler]

I think that is perfectly feasible in the sense that the 'bucket' (I'm more imagining something shaped like a jet engine filled with screens) is going to cause drag. If it is not enough on it's own then having the chute dragging behind it would be fine and would keep the thing pointed into the wind. Their might be some conflict in which altitude is optimal for each device though, the maximum acidity level for the collector is unlikely to be the ideal location for a parachute, the chute is going to need to be very acid proof if it lives at that altitude. Still that seems better then trying to have two separate things dangling under the blimp, the inevitable tangle is just so obvious.

The Acid solution naturally decays back into water vapor and Sulfur-Trioxide when it's heated in the lower atmosphere to 300C, perhaps this is all that needs to be done. I think I also read somewhere that CO might do the job, would steal an O atom leaving sulfur dioxide and water, can anyone else confirm?

Edited January 13, 2015 by Impaler