AngelLestat

I guess there is some logic about the position and tilt of the engines. If we take into account pair production effect as source to increase efficiency, then this will mostly happens at the same flux direction, because gama rays has more chance to find particles to hit and became particles them self, which can be focused by the nozzle. So if a gama ray travel in opposite direction to the exhaust, then there is less chance to became particle again. In this case most of the radiation (which can not be focused) escape to the front of the ship. Then we can ask.. how much of that radiation absorb the ship and the crew. The crew just a bit, because for the effect that I already mention and the square rule. The ship not so much either, because gamma rays are very difficult to stop, you need materials with high atomic numbers and thicker. So if the ship is base on graphene (carbon) composite, very thin, strong and light. Then mostly all the radiation escape to the space without increase heat.

But I said 6 to 10 times the volume.. not the amount of helium. The amount of helium you will need it will be 4 times, i guess. (venus at 50km Vs Earth at 10km) Example: if we have a blimp with 100000m3 full of hydrogen will lift: 160 tons at 50km altitud in venus. Amount of hydrogen needed (mass): 7000 kg The same amount of hydrogen at 10 km on earth will lift: Volume 263903 m3 Lift 31 tons. So if I want to lift the same mass I need 4-5 times more hydrogen and 12 times more volume. Also we can not use hydrogen at earth, we need to use helium and this is too expensive. If there is an error with my math let me know. I am sleep, so maybe I wrong.

In what year was cancelled? Can you post some info about that? But there will always mission which are approved and other that are cancelled. This does not mean that they were cancelled because the ISS Take a look: http://solarsystem.nasa.gov/missions/profile.cfm?Sort=Chron&StartYear=2000&EndYear=2009 Tell me if you find some decrease or increase in the amount of missions over the apollo or ISS construction. Also the ISS never had the marketing as the apollo, because it was in low orbit and russian had a space station before. But the ISS must continue, it force countries to always keep it alive with several launchs, this encourage agencies to search a cheap way to launch stuffs. It does not decrease the space exploration in any way. If the ISS will be abandoned, then % fed budget will also decrease. The problem with is that you lose lift capabilities over height. You will need a ballon with 6 to 10 times more volume to lift the same weight at 10km than venus at 50 km. And you need to fill that volume with hellium or hydrogen.. Hydrogen is cheap but dangerous here at earth, if you use helium you lost all that helium (which count also as fuel) A better possibility will be use a variable buoyancy vehicle to rise the rocket. In this way you just consume the energy to compress the hellium. By the way.. I present this transport concept 1 year ago, everybody said that it was crazy, that this thing dint have any economic possiblity, etc. Now there is 22 in production stage, 4 of 66 tons, and 18 of 250 tons, with new orders in hold, until they gather more, to see if is convenient to open a new factory. It does not have sense What about your wind opinion which was related as the main excuse to not go venus? ------------------------------------------------- merry christmas for those who follow this tradition.

venus has also co2 ice crystals at 80 to 100 km height.

Read the second answer of this post and you will understand: http://forum.kerbalspaceprogram.com/threads/103899-The-physics-of-avatar?p=1622122&viewfull=1#post1622122 "Second, I calculated the energy required by the laser to accelerate 1000 tons (we dont substrate the mass here). This give us 2 Pw by second, how is possible that I have a similar value when the laser needs to give 150000000 times more energy than the required energy to push the ship with rockets?" against the video energy requirements using rockets on the 1250tons case. It has no sense.

Let us know if you achieve this.. of course is time consuming. Just some ray cast of few particles will be enoght to have an idea. But it sounds hard anyway.

Ok, lets try again, NervaFan answer was goof enoght. I will try to clarify a little more. About what a manned mission can do than a robotic cant.. plus why sent people, I explain this already in many previous post. You can quote me from there, but read them all. Here some data. http://en.wikipedia.org/wiki/Budget_of_NASA Take a look the % fed budget and year. Right now the % fed budget is in free fall because lack of public interest, the only 2 times that increase was over the apollo program and ISS. That's what people wants. There is where you get extreme budgets. If NASA keeps doing unmanned missions the budget will decrease with the time, so you will have less mission over time, but if you find something to inspire the world you can get several times that budget which will not decrease your future budgets, In fact it will increase them. Also you have the excuse that you do to understand the risk that earth face and what to do to save us. why you think venus winds will present a problem?? Even high winds in earth 200km/h does not present a problem with high altitude manned ballons. And earth winds has turbulance, you have also vertical winds.. You dont have that in venus.Of course we need to be sure, for that reason we will sent a unmanned mission first.. But previous missions at that height show not signs of turbulance. I can explain from many angles why is like that. With evidence and all kind of data. Fly with airships in Venus is much much much safe than at earth. Here an importat fact why this is shocking to so many.. In the space competition between Russia and USA, they choose to focus in one planet, this was because the few probes sent to mars by Russia fails, and the probes sent to Venus by Nasa also fail. So they thoght that it would be a waste of money and sign of weakness try to reach the achievements already accomplish by the other. Also like USA always was the media master. They sale to Venus like a Heal Planet who had not purpose, and mars like the human destiny. But Russia knew the possibility to colonize venus cloulds even back then at 1970. http://i.imgur.com/IEHMEni.jpg And now Nasa realize that Mars has more drawbacks than they thoght before.. So now they try to change perspective. lets leave it that way.. its clear that we have two very different ways to think about politics, public opinion and budgets. The time will tell who is right. Although the past, gives me the reason to me.

You give me the reason about who has more common sense in space economics just by mention the word "trillions". With that start, it will be very difficult to explain you why is like that. The ISS cost from its start to now is 153 billions, this taking into account that they use mostly the space shuttle to make it. (not cost effective at all) Mars direct cost is 30 Billions. My estimated cost of this mission until phase 4: 60 Billions, this include the remaning development cost of the new NASA launcher (which will be used for mars missions), the first probe mission to venus, the second 1 month manned mission, and the third 1 year manned mission. 80 Billions as top, who wanna bet?

More usefull than improve our climate models and understand with certain our current fate with the global warming, which may save us all?Not mention that is much cool than a moon mission. Is not an entertainment company, but once a while they need to inspire and gain the people interest. Because PR you like it or not, its what define how much budget you receive for certain mission. Read my Karriz answer. That is the thing they dont understand. They think that there is a fixed budget and you need to choose what to do. Noo. In fact if this mission cost billions, it may open a new budget for another manned mission with even higher cost, this without touch the anual nasa budget. If you said: "not.. I dont want it..." they will spent that money in other military toys, right now the budget difference between military and nasa is 50:1 But some people (some scientist included) had the wrong ilussion that if they reject the budget for these manned missions, the goverment will said: "-well I give you the same money, use it as you want." That is delusional. Nasa will answer, "-well then lets sent 100 probes missions", goberment.. "-why you need so much? noo.. we cant tell people that we spent money in 100 different mission to do the same thing or similar things". Not to mention that those 100 mission will be out of radar from the 99% of word population. At the end they will said "-take.. here you have enoght for 2 probe missions.. good luck." For the first mission they will bring the fuel with them. You can make hydrogen from the atmosphere for sure, but we didn´t test nothing yet to collect sulfure acid (the hardest part) and extract the H2, we can convert the co2 to be used as fuel, but not sure how usefull it will be. The manned sumbmarine Trieste reach 11.000mts of depth back in 1960 in the pacific, so pressure is not the issue. The only issue that I see to colonize venus is water. You can get it.. but is not easy. You can recycle once you have it all the times you want, but you will need to use in process as "rocket fuel" which you need to gather it again. Graphene (Carbon) is good resistent to sulfure acid lower than 75% and very bad for higher concentrations, some micro doplets may reach 85% in venus. The best elements to counter high concentrate sulfure acid are: Viton, pvc, polypropylene , ceramics, noryl, teflon, kynar, tantalum, hastelloy -->full time Neoprene, zirconion, nylon, latex --> only for limited time, maybe months. But you start with 85% of gravity, and it drops faster than here at earth, because you already are at 50km. Can you remember me how to calculate the low orbit speed? But that is the error, they dont not compete for funding. If they found that they can go mars first, then is ok for me. But if we dont have yet the technology to go there, instead wait 15 or 20 years more, I want a manned mission to venus first. And it does not mean that if you make a venus mission first you lost the mars mission. Because the first gets more public attention and they will want more. Also technology used in the first can be used in the second.

nobody did a virtual representation how things will look from inside the bubble and from outside?

Yeah agree, and if this happen, I hope you make the mod -Hooligan Labs is not real enoght. Ok, one social experiment for you, ask anyone in the street about space activities they may know.. they will mention when we go to the moon, ISS, and maybe hubble and voyayer. Maybe they hear about other missions, but they can not give any name or detail of those missions. They already sent ballons to venus but without camera.. when they sent probes they dont care about the public, also they have so limited bandwith that is only enoght to get some science, but not much to show. There was already a lot of mars rovers, yet even this is the only that people may see. BORING is the word. You think this is the way to get people attention? Nobody really cares about these missions, taking into account that people are who paid for these missions, if you dont get their attention, you will have less money to invest in space. I will show you how to get people attention: HAVOC, The mission project to fly through the Venus clouds, destined to understand the earth´s fate against the biggest problem that humanity even face, the climate change! Join the crew in this risky journey since the apollo mission or colon, to solve some of the misteries hiden in our twin hell planet, to avoid make the same mistake here on earth. Real time pictures transmissions with brief resume at the end of each day. Post documentary of 10 chapters showing all the trip odyssey with the 100 TB of data collected of all sensors and the 5 HD camera recording full time. Merchandising of the mission, with RC blimps at scale, PC game including all missions phases (build your floating colony) and the movie. Thats is how you get in no time, the next huge budget for the next mission you want to do, at the same time people understand that the climate change problem is real, more if NASA get in so much trouble to find an answer. Without mention the prestige that NASA and goverment will get with this mission Well the amount of atmosphere that you need to cross from that height is the same as earth, but the venus gravity and circunference is lower, So I will said 6500 to 7000m/s. A blimp in the venus atmosphere at 50km has 30% more lift than a blimp at earth surface. But if you wanna launch a rocket from 10km of altitude with a blimp here on earth, you will need a hugeee blimp because the atmosphere at 10km is too thin. If you wanna take things from the surface if you have a cloud city, the best way is with a hot "air" ballon, you just heat the gases inside your envelope to be more lighter than the surrounding, you need a nuclear heater instead combustion. I know, but is not the best place to get public attention right now. A mission to Venus, which is much more expensive, you get some of that money back just because it has more marketing. And I am not saying you get the money from the media, you get the money because people get most interested in space, so they will not put excuses in the senate "why we are going to the moon, we were already there, there is things more important to solve here". Your budget limit it does not depent much of the country condition, it depends on the public opinion.

Lol OMG, why are you so negative against this movie? something really bad happened while you was seeing the movie at the cinema? About unobtanium, If that is the right name that engineers use to describe a wonder material, then if you find such material with wonder properties, you can called unobtanium. Maybe graphene could be called that way. There is a a huge difference between fantasy and science fiction. Avatar is science fiction. Antimatter was already created, it was already contain, they also measure the energy release when it touch normal matter. Every year scientists rise the superconductor state some degress more. And they dont understand yet the physsics behind superconductors and superfluidity. So they are just guessing in each try. Laser sails were already tested in laboratory. Sorry, but all that has no relation at all with pseudoscience. I wonder if the scientists who designed the apollo mission, they had to gather in the fantasy room to plan the mission? Now name me a movie with a interstellar ship more plausible than the Venture Star. Note: James Cameron didn´t design the ship, it was Charles Pellegrino and Jim Powell, two physicist. -------------------------- Now back to the topic, someone knows why the kinetic energy requirements to brake differ so much from the one you get with a=F/m?

Moon again? after 46 years our biggest next step will be moon?? And mars is out the question for the next decade, there are many issues which are not solvet yet.. too expensive and risky. But a previus mission to venus may help to push a mars mission. People tend to think that if you do one, you will not do the other. But not, is all about getting the people attention. ????? who said that? try to focus in the discussion. If you make me a question I answer. But you need to take into account my other answers instead come out with these comments. http://ceres.larc.nasa.gov/documents/STM/2010-09/28_Bony_CERES_ScienceTeam_sep2010_final.pdf “... the modelling of time dependent clouds is perhaps the weakest aspect of the existing general circulation models and may be the most difficult task in constructing any reliable climate model†http://en.wikipedia.org/wiki/General_Circulation_Model The effects of clouds are a significant area of uncertainty in climate models The clouds of Venus are still a mystery, its effects are completely different from our predictions, solving that will inprove significantly our current models. We dont know yet, but Mars direct (I am a zubrin fan) showed to be too risky, it fails to provide the minimum safety requirements, but I guess you already knew this. But is not only that mission: http://www.wired.co.uk/news/archive/2013-05/31/getting-to-mars http://rt.com/news/199240-space-...-mars-colonization/ http://www.extremetech.com/extreme/191862-the-first-mars-one-colonists-will-suffocate-starve-and-be-incinerated-according-to-mit Why you need to drill? You use the same Radioisotope Thermoelectric Generator to melt the ice all the way down. It just need to be powerfull enoght. The ice that it melts will instant sublime due the lack of pressure, so you have a hole like the one you will make with a drill. So you keep connection with the surface through a cable. At least that is my idea. yes me too, because I said a lot of times all the reasons why we need to sent astronats, being the most important "to inspire a new generation" and because we can not go to mars yet. - Come on, "yes they are" isn't a valid reason.but I already answer this in previous post, and I was not the only one who answer this. - What are you going to do with "many terrabytes" of space? Cassini has sent close to 500 GB of data in it's whole 10 year mission. You think you the HAVOC mission is going to produce more than that in 30 days? We dont have 10 years, and we can have 10 TB in just one month. It can record in full HD in all frequencys all the trip, Havoc in its whole journey will travel 285000 km, 7.5 laps around venus. - But of all places, why Venus? At 52 km, Is the place more similar to earth in the solar system. Also due all its advantages. I love it. As I said before, this is a new idea for NASA, they never realized of this possibility until now... O2 is not the problem, that is too easy in Venus.. We need to figure out how hard is to get water from the atmosphere (the tiny sulfure rain). From the last probes, it seems that wind is not a problem, is too constant in the whole planet without turbulance.. of course we need to be sure. But water its the biggest problem for colonize venus. There is 15000 km3 of water in the atmosphere, but the atmosphere is so thick, that is almost nothing in comparison. People see sulfure acid as a problem... but I would love if it will rain as at earth the same amount of acid there. Then it will be too good to be real, a perfect place to sustain a new civilization and economy. Yeah, lets sit here to watch TV as in the Wall-e movie, meanwhile robots fill their lifes living all the adventures which we are too lazy and death to do it. Lucky for us, robots still can not perform so well as the ISS astronauts do. Before post, I search for a similar topic, but I dint notice any. Also I post it in the first second which gizmag publish it. So I dint imagine that it was a 2 day old news. Agree.

so a superconducor material at room temperature can not exist? Antimatter propulsion can not exist? A laser sail can not exist? we are using the newton and einstein formules to compare the numbers, we need to do that in a different forum section?

they should joint forces.. yeah that.

Why not? what is your next step then... Humans in GEO? In my case, if they go outside the airship at 52km height with just an oxygen mask, they will make my day and all my future days. Maybe that is too much to ask for the first month mission, but it will happen for sure for the next 1 year mission. micro droplets you may said.. Imagine the amount of water in our atmosphere, 40% of humidity (you get wet with that?), in the Venus case there is a 1% of water-sulfure acid humidity. You can be naked outside by 1 min or more, and you will not feel absoluty nothing. Extra time and you might start to feel some ardor in the skin. Also, nothing that any latex suit (with mask) can not counter. I dont know other way to explain it.. Read the pdf. You think that I made it up? Not ask me, ask to the meteorologists. Of course than several different missions to venus will collect more science that a single manned mission.But we need a manned mission too, and right now a manned mars mission is too expensive and risky. Maybe this mission can encourage people interest to take the next step in mars. For a life search quest, I would preffer an unmanned mission to europa under ice lakes. More chance to find complex life there. Because we dont know for certain what we put in motion burning already the 50% of fossil fuels who was storage over 1000 millions of years. We know that some mass extintions happen before when similar amount of co2 was burn due massive volcan activity who burn huge carbon reservoirs plus forests. Now we have a chain reaction effect which extra co2 melt ice, then earth reflects less radiation, then methane reservoirs escape to atmosphere, temperature rise, more water vapor reach the atmosphere which rise even more the temperature. And right now we can not predict the right values of all these process. Because our climate understanding is basic. Also understanding the climate, we can focus our resources in the best way to prevent this, maybe there is a better way than just cut our co2 emissions. The biggest problem of humanity is global warming. (well in fact is the same huminity it self, the increase in poppulation) - Time delays and bandwidth are a non issue for observational experiments. yes they are. - We don't have meteorologist in Space to predict our weather, because sending the data down from satellites works just fine. why they will be in space? if the atmosphere is right here? lol - CCD's on cameras(depending on their application) can see the whole electromagnetic spectrum, the human eye can only see visible light. So you would want to send those. you have limit bandwidth, here you can go back with many terabytes of data. - Curiosity landed just fine with out the help direct human input and it's the most complex craft that landed on an other planet, deploying a few probes should be trivial in comparison. I already said it, I am agree that is always cheap to sent a probe than a human.. But we need a manned mission too! Now.. in ten years, not in 30 years. If Nasa officially stated they were going to mars, then you will find a trace of that manned mission on their site yeah of course. The topic tittle it said: "they are considering"

You cann´t blame NASA, this vision to sent humans at the Venus clouds is very recent for NASA, they never thoght about this possibility before. Of course soviets did since 1970, because they were the Venus masters. But in the west, the first scientist who realized about this possibility was Geoffrey Landis few years back. Is a big change of perspective, but there is not much difference; we can go to a planet to float in some liquid, to be on ground, or to float in their atmosphere. I would love to also explore Jupiter with a hot "air" ballon powered by a nuclear heater. With this you can choose any altitude you want, it does not matter what gas you have inside your envelope, if you heated, it will be lighter than the surrounding. Nasa knows that they need to plan a new manned mission to some place (not the moon) to capture again the attention of the world. But mars is still too risky without ways to abort. This mission is a lot shorted, 400 days VS a 600 to 900 days mars mission. Also until you dont receive the money, you can present any different mission, only after you start to work hard in achieve that. So there is no time lost here. Ok, that is kinda negative.. but more reason to watch it in TV!! To be 100% honest. There is 3 robers in mars, and nobody gives a ****, I am not the exception. Thanks, but I expect some extra info, this project it does not seems to have an official web page. EDIT: Albert, I will answer your post later.

That is the wrong approach, these tanks are just draws, even if they had certain measure, you need to take into account how to keep them cold and contain with magnets, then there is the issue of density.. There is experimental evidence that a hypothetical state of deuterium would be 1 millon times more dense than liquid hydrogen. So how we calculate volume if we dont know nothing about density, magnetic confine require, etc. How to storage and gather antimatter are the concepts most difficult to solve in antimatter propulsion. So lets keep them out of this discussion. Lets make something clear. We can not keep talking about different mass ratios, we need to choose one so we all have the same number. From my part, I have plenty of evidence which show that the dry mass is close to 350t or 400t. And the wet mass is 1000 tons (or 600 tons if we use a magnetic sail to brake, it does not add mass) So if someone disagree with my mass estimation, lets see who present more evidence to prove me wrong. Now about the video. He calculate the required energy by second to brake from the kinetic energy approach. But I dont know.. something is wrong with that. First he calculated for 1250 tons, but if that is the wet mass, then he forget to substrate all the mass that ISV loss meanwhile the fuel burns. Second, I calculated the energy required by the laser to accelerate 1000 tons (we dont substrate the mass here). This give us 2 Pw by second, how is possible that I have a similar value when the laser needs to give 150000000 times more energy than the required energy to push the ship with rockets? Sail: (F*c)/2=p 6.7N by Gw a=F/m KE=1/2*m*v2 In addition, its heat calculations are wrong. I explain already the amount of energy that the ship absorb. And is magic how the radiators area match my heat waste requirements.

wow, i love it.

yeah, I always mix the names. And K2 explanation not always help, I find troubles linking sometimes the cassimir effect with this.

No I am not.. you dint see the second link? I want you watched all, but I dint wanna force you to spent 15 min doing that. I love the whole discussion, and I invite all to see it. Also we learn things more efficient when we look our selfs reflected in somebody else doing the same thing. We are still like any animal in that. Chimps learn things a lot faster when they copy the actions from their own specie. So there is when these actions capture the attention from the whole world. We can learn reading a book, but going to school and lessen a proffesor we understand things faster. This is explained in psicology. So lets not remove the need to see another human being in another planet. That is something that the humanity needs. Also we already saw humans with a space suit, but the only place to see a human without a space suit in other world is in Venus. Is cheaper to sent humans to venus than mars, also safest. And it will be awesome! sure, but we still need that source of inspiration to embrace a new age of young scientist. I dint find details about the probes launched from the manned blimp yet. But I saw many times projects designs who solve all those problems with ease. I can search the PDFs if you want. They did already that in 1975 to 1985 with the ballon probes.

Kip Thorne in his book about the science behind Interstellar (movie) explain how millers planet has an stable orbit around a supermassive kerr blackhole at 2,5 radii and it also explain the complex eliptic orbit of man´s plannet, which goes from 600 radii to almost 5.. Of course this is a rare case were the black hole is spinning ultra fast, so you may be right in more general cases.

http://youtu.be/40YIIaF1qiw?t=28m55s That is the key moment that I wanna share. But the discussion on probes-vs-humans starts here, and I encourage all to watch it. http://youtu.be/40YIIaF1qiw?t=21m23s Albert, I know that gravity bends light.. this mean that we can solve singularities? We have a math model to predict our climate. But is not complete, it has flaws in some areas. We dont understand much about clouds, hurricanes. We can not predict what is the real fate of earth on global warming, we have some rought estimations in short periods but we dont know for certain in what mess we really are. The model may work fine in some circumstances. But that is because was made it and corrected to match predictions with the things we measure. But a good model needs to work fine in any circustance under any atmosphere. And it doesn´t. So only when we use the same model with two different parameter values and then we compare the predictions with the real measures taken. That is when we find the key to solve all the flaws that our math model may have. http://www.lpi.usra.edu/vexag/meetings/archive/vexag_9th/augSept11/presentations/WhyExploreVenusNow.pdf Venus has a lot of similarities with earth, gravity, amount of co2, it had similar amount of water before, similar pressure and temperature at 50km height, etc. Also finding an strong evidence about the global warming and our atmosphere fate, may force to all nations to take the issue much more seriously. Yes, and now we can try to become friends of this bacteria so we dont feel alone anymore. If almost all life die due a climate change, then that question takes a new meaning. The main advantage to manned mission (lets ignore the publicity and inspirational advantage) is that you dont have time delays or lack of comunication due planet rotation, bandwidth to sent information, etc. In the same way a geologist may be a lot more efficient in mars than a rover, applied on a meteorologist in venus. A meteorologist can saw the cloulds formations - colors, and understand a lot more what is going on. They can know if a sample may be contaminated or not, etc. They will also sent probes to the surface from the blimp, and you need to drive them in real time. well said.The key advantage is that we can test anything about this mission in our own atmosphere. We can not do the same for mars. You dont need manned missions to the venus surface, if you have human pressence in the atmosphere, then you can command any robot by virtual reality as you will be there. Why they talk about helium airships? hydrogen is a lot cheaper with extra lift, and venus does not have big levels of o2, is all trapped in the co2, so there is not risk.

In this case I am agree zetax.

before answer you, please define "too close". I am agree with the rest of your explanation, but I wanna add: there is absolutely nothing preventing you from making the space englobing the ship move faster than light which we know about it. There are some papers who find troubles with the stability of the bubble when its close to the speed of light. Also I keep reading each month a different explanation to negative matter. Which may give us a clue that there is not much we can said for certain on negative matter or to describe its properties. I even hear a theory that said it may be made from ordinary matter.