AngelLestat

Autogyros are more reliable than parachutes and can face strong winds or turbulence with the mentioned bonus of guiding and soft landing. You are replacing dracos by rotor blades, so you are losing the great benefic of the escape system which is a 40% or 60% more light than the tower design, and you dont need to eject that (which contributes in the cost), you can also use that extra deltav in any emergency during orbit. About rotor blade propulsion, you can have that even with compressed helium, this was being mentioned in the nasa study on this tech. It was not necesary, but increase the safety. But well, I can not said that rotor blades will be more reliable than parachutes in the capsule or booster escenario, because the tech would be more complicated because it needs a good deployment system, only a good design and time testing will tell, personally is something that for me it will be a pleasure to see, I am tired to see how the world stay in the past just by fear or lack of inventiveness. Of course we can not ask more of Elon musk, he already did a lot, is the time for somebody else to try something new. The RCS thrusters in the top booster stage just points the inconvenience of landing with a propulsion force from below. Surely you've tried this in KSP, not matter how strong are your tops RCS, once the angle is more than 2 or 4 degress, there is not going back. Their software can be very good (in time) to ensure +95% of recoveries, But with the other way would be ensure 100. PD: grid fins does not work at low speed, so the final touches are all rockets.

Ok, A lot of misunderstandings.. I meant for a future dragon version (I am not saying they would do that, I said that is the thing I would like to see). Is not as backup for the draco thrusters.. Is the other way around, the draco thrusters would be the backup for the autogyro. Because there is no other way of execute a soft and guided landing more reliable and dependable than autogyro. The weight will be the same than parachutes.. so you remplace the actual parachutes with an autogyro. About the stage1 booster, if you have short blades, enough to decrease the speed at 10m/s close to the surface "changing the pitch", then it will weight a bit more than normal grid fins, but you also save a lot of fuel that you need to use for guiding and the fuel needed to reduce the 100m/s. And guiding and landing using rockets is a lot hard than using autogyro. The stage is too long which it makes too hard for a "force" to balance the stage from below than above.

If spacex (with extra development) would remplace the grid fins by small-medium size autogyro blades, then the guiding would be a lot easier, and you can reduce a lot the braking speed and (corrections) made by the propulsion system. Then I will like also to see an autogyro system for a dragonv3 capsule in remplacement of the parachutes, then the autogyro would be main option, and if that present fails, then the propulsion method as alternative landing method. But this tech will take some years of development, because the deployment at big speeds is a challenge.

My dirty mind was expecting something different with the topic title

How I said, it depends on the black hole itself and how fast is rotating. Kip thorne in his book also explain in detail how to steal energy from a rotating black hole using the ergosphere. For example if you have 2 massive black holes orbiting on each other, with a ship you can travel between the different ergospheres many times until you leave the system at the speed of light in any direction you want starting from a low speed. Second about the beacon, they knew very well the exact time dilation that miller´s planet have it before leave the endurance, but they only knew for certainty that the planet was a very bad idea after being 1 hour trap there, never would be a good home for the human race, due asteroids and different stuff trapped in the black hole field. But in their perspective, you also need to take into account, that they thought that one of those 3 planets was the human salvation because an "alien race" put a bridge for them there. Also they were alone with all their decisions.. Because in earth they knew almost nothing about miller´s planet. And yes.. I know what is frequency shift... but they receive the data from a sat relay they left close to the wormhole, when they cross the wormhole they receive all the data which was only "ok" messages. And it does not give more detail in that. But if you want better explanations, mines are just sentences from what I remember. You will need to get the Kip Thorne´s Book and read it, there are 400 pages with all the movie physics and concepts explained with good detail. He is an eminence in black holes, gravity waves and wormhomes. In fact the ligo experiment (now lisa) that now everybody is talking so much was designed by him. The propulsion is fusion if I don't bad remember. Also nobody should forget, that is the first movie with real visual about how it will look a wormhole and a black hole.. Just for that, everybody should be thankful.. The wormhole in Contact movie was a disk :S (also one of my favorite movies)

Thanks, one issue less.

if they are advance.. they might have neural networks to decode all our languages.. if they had neural networks.. then not sure what are they still doing here.. (in this universe)

congrats for akatsuki.. I hope this planet start to get the attention that it deserve.

How we remove the extra space between each paragraph each time we press enter? Like this.. blah blah blah.. It takes a lot of space. Is like we press 2 times enter. I cant find any setup to change that. Also utf8? where I can set that?

Falcon Heavy all the way.. vulcan will be a waste of money, it will have only a few commercial missions before realize that they need to go back to the design table.

Negating the reality? I show you Honda Clarity pictures and properties, 700km, only 3 times more tank volume (not 4) but you save a lot of space with the engine.. So in resume.. It consume the same space. Taking into account that h2 cars are just new and they will keep improving. They dont pollute and you save half of the money in fuel. The fuelling time is 3 min. Uh sorry, you need to wait 1 min longer. Lol.. OMG so much rage against hydrogen... Sensors are cheap, and many of those are just there to increase the fuel cell efficiency that as bonus point also help to detect any leak, the same that you have a lot of sensors and a computer to manage all valves which is called the "injection system" in gasoline cars. About hydrogen sensors: https://ec.europa.eu/jrc/sites/default/files/Hydrogen%20safety%20sensors_en.pdf And there are more cheap and small sensors in the way using graphene oxyde for 2017 or before. You are also ignoring all the points where hydrogen is safer than gasoline. As I said, is not more dangerous, is just flamable as any fuel, it has different properties and you need special devices the same as any fuel. With a [poor] range and waiting 20 min in recharge? And all that with a battery cost equal to a gasoline car cost? Batteries are not bad, but there are not being made for big and heavy cars, the cost is too much not just for production limitation, for a nature law give it by the energy density, weight and materials. Meanwhile hydrogen fuel cells or electrolysis are very close to get rid of the platinum, and they still need to reach the production rate that lithium batteries already had. That is why all the new hydrogen tech companies are showing higher cost of shares in the stock market. What you want I said? is already happening. Because countries needed as storage, car makers needs a vehicle with high range and low charge time with a future potential low cost. They also need a co2 free system for trucks, ships, and any other kind of vehicle. Even the army is testing tanks with fuel cells.

1-Its mention in the same movie, they use a neutron star as gravity assist to reach miller´s planet and for go back to the endurance. For this we need to remember that miller´s planet is traveling at 0.45c, but the wormhole is also orbiting the black hole. In the book kip thorne said that a neutron star will not be enoght to the manuver because it would break the ship, that he will needed another black hole (instead the neutron star) orbiting gargantua, but Christopher Nolan dint wanted 2 blackholes because it would be confusing for the audience. 2- You mean decoded from earth or the endurance? From the endurance they knew that the planet had a huge time shift, but I guess that in earth they dint know, they just knew that 3 astronauts saw 3 potential worlds. 3- Gargantua is a rotating black hole spinning at 0.999999999 the speed of light, in fact almost all supermassive black holes rotates at average 0.9999 the speed of light because each piece of matter that falls increase their speed, but this particular black hole was even faster. This rotation drags spacetime with it, and miller orbits gargantua in opposite direction of its spin. The black hole from the movie would look like this (this images is not a full render, it lacks brights and colors), but Nolan was in love from the full ring bright look. A rotating black hole It has 2 photon spheres, that´s why is so wide in the picture the photon sphere. Then you must be wonder on all the deltav maneuvers on mans planet, this is not mention in the movie, but mans planet has a orbit very eliptic, from 600 au to 5 au from the black hole, So if you are in the far from the periapsis, just a little change in your orbit can take you to the black hole.

Ok I will not quote because there is many people saying the same thing. Hydrogen volume: too high to be used in normal vehicles.. Honda clarity: Range 700km, space required (the same than any car), cost: 50000 EU, but much cheaper in japan, tanks capacity: 150 liters (3 times more than gasoil tanks as I said) http://www.cnet.com/products/2016-honda-clarity-fuel-cell/ http://www.forbes.com/sites/joannmuller/2015/10/27/hondas-new-hydrogen-powered-vehicle-feels-more-like-a-real-car/ Pictures: Free space in the front - Trunk - from side - H2 Tanks Hydrogen is hard to handle and not safety... Hydrogen systems are super safe, I will said more than any other stuff using fuel. They do it that way for the hysteria that people has around hydrogen. Any leak is detected by tons of sensors and valves that measure how much hydrogen you charge and use it. Windows open automatic if that happen. And even if they dont.. hydrogen escapes anyway. Tons of extra safety measures that I will not even mention. Gasoil gases and liquid stays close to any leak and waits until the right moment to BOOM. Hydrogen leaks in seconds and always the flames goes up. Tanks are hard as rocks, they can hold hydrogen by a lot of time (they are not ballons) and they can not explote. They can resist bullets. And even if you use a barret, it will just leak fast without explosion. Each fuel has their procedures, measures and devices to be handled.. This is true for gasoline, gasoil, natural gas, jetfuel and hydrogen.. Of course you can not use a gasoline tank with a gasoline expenser to handle natural gas, neither natural gas devices to handle gasoline.. Is stupid. The same happens with hydrogen devices and dispensers, they will be just different. There are new ways to detect hydrogen already test it but still shaping the final product like thermal cameras, and graphene oxyde that is cheap and can detect hydrogen % in the air with great accuracy. Batteries are better: Depends, if the car is light or does not need long range, then yes. But batteries are expensive, Why all lithium batteries cars are luxury class? Because they need to camouflage some way the price of batteries. Today Tesla car batteries cost around 25000 the whole pack, if we wait until 2020 when the gigafactory will be at full capacity the cost will drop a 30% --> 18000 dollars. But for that cost you can buy a whole new car. That cost will not drop until they arrive with a new battery tech (air battery which will take at least 8 to 10 years). In addition, batteries has a lifetime, so eventually you need to pay for a new full pack of batteries or change the car. Fuel cells in few years achieve a great improve in power density (4 times smallers for the same power), they also become cheap, and that taking into account that we need to wait 1 to 3 years to remplace platinum with cheaper materials without decrease efficiency. Different ways to storage hydrogen. Liquid cryo: In this form has the best energy density by volume, but you lose a 40% of the energy in the change of state and temperature lost. Now there is a new way to liquify hydrogen using magnetic refrigeration that only lose 20% of the energy, this is not a problem with future h2 jet airplanes, because you use that cooling and you help to expand the gas with the heat product of your speed. 700 bar: the most used today, you lost just 3% of the energy. 350 cryo compressed: New standard (germany used both), This has a little more density by volume than 700bar.

Is not hard to make work any gasoline engine with hydrogen, in fact here in argentina, 1/5 of the vehicles use a modification that cost 500 dollars with tank included to to run on natural gas (because here is subsidized for some silly reason), but if you charge hydrogen instead natural gas is the same. Old zeppelings instead vent the hydrogen, they injected into engines to gain a lot of range vs helium airships. The history shows me no interest in the co2 emission and there was not renewable energy sources cheap enough to capitalize that. Is not more dangerous than natural gas, and we use it in all houses. Hydrogen has bad reputation which is not deserved, promoted by USA since airships times when they wanted to exploit their helium resources, then the bad reputation go back when oil companies also look at hydrogen like some kind of competence. LIthium batteries are not so safe, they can get fire very easy at car energy density, a new kind of batteries are coming to solve that issue. Another benefic is that you produce the hydrogen in the same h2 stations, that reduce a lot the energy loses and the transport risk. What number I made up? The extra 10% to 15% of hydrogen jet turbines? The 25% fuel reduction with the new nasa blended body design that also increase the internal volume? Or the fact that if the airplane will weights 1/4 less due hydrogen amount and mass which it will translate to a new 20% decrease in fuel consumption? Also dangerous and impractical?? Why you don't provide some examples of how liquid hydrogen with their safety systems will be more dangerous than jet fuel? If you use electric engines with fuel cell, your are increasing the fuel efficiency by a factor of 3, so you need 3 times less fuel to keep the same range. This still requires 3 times more volume, but electric engines and fuel cell require less space than a full otto engine with their gas escape, radiators, gearbox, alternator, etc. And hydrogen cars just started, the technology will keep maturing decreasing the cost and volume.

This is not the same than classic religions that are part of our culture and modern civilization presenting obstacles and pushing things in base of ignorance (or not proven things). The same that nobody can demolish a building or damage a place if is proven of culture value / history / art / or attached in some way of special feelings. Why we have the right to decide what value has this on a different culture which is placed in its original habitat? But well, lets destroy the navi´s tree to obtain more unobtainium, if they complain we buy them some jeans.

Yeah methane is also part of the hydrogen economy as I mention before. But I want to extend PB666 words on airplanes. Today airplanes need normal fuels because they were designed for that, but this does not mean that we can not design an airplane to work with hydrogen, which is better fuel for airplanes than normal jetfuels. The first clue... Skylon.. It would not be even a paper design without that fact. Hydrogen is 3 times more lighter and it takes 4 times more volume (cryo liquid) compared with jetfuels. An airplane with hydrogen will have 3 advantages. 1-High efficient engine: A jet turbine designed for hydrogen has the advantage that it can work at higher temperatures without melting because you use the same hydrogen as cooling, so the carnot efficiency increase, plus you recover the energy lost in the liquefaction because you help to expand the hydrogen with the heat. 2-Blended wind body aircraft: This type of body-wing shape allows extra volume but the most important decrease in a 25% the fuel consumption. This is achieve due PB666 points, like noice reduction, higher lift --> higher altitude --> decrease of drag. 3-Hydrogen energy density: So if we combine the 2 previous points, we have that we can save almost half of the fuel, but that half of the fuel with hydrogen will weight 3 times less than normal jetfuel, it means that we can achieve higher altitude --> less drag --> less fuel consumption, In resume it will be possible to save 55% of the fuel, this mean that we need just 2 times more volume that is included in the shape.

Lol... why you dont check reality before make such statement. Hydrogen will be the number 1 energy storage method in the world for reasons that I already explain. All these selected news have something in common, they are all from today or yesterday. http://de.total.com/en-us/home/media/list-news/total-opens-hydrogen-fuel-pump-innovative-cryo-compressed-and-700-bar-fuelling-technology-munich http://www.bloomberg.com/news/articles/2015-12-03/germany-joins-global-group-to-encourage-zero-emission-vehicles http://www.businessgreen.com/bg/news/2437427/ceres-fuel-cells-aim-to-shake-up-residential-and-commercial-markets http://globenewswire.com/news-release/2015/12/02/792241/10157701/en/Connecticut-Hydrogen-and-Fuel-Cell-Industry-Expanding-as-a-Global-Leader.html http://www.hydrogenfuelnews.com/mercedes-benz-expected-unveil-new-hydrogen-fuel-cell-car-2017/8526208/ http://www.njherald.com/article/20151202/ARTICLE/312029983 http://www.greenoptimistic.com/japan-renewable-energy-options-2020-olympics/ http://www.businesswire.com/news/home/20151201005286/en/Annual-Fuel-Cell-Car-Bus-Sales-Expected https://www.energyvoice.com/other-news/trainingtechnology/94396/afc-energy-focussed-on-the-future-with-its-fuel-cell-technology/ http://www.gasworld.com/fuel-cell-buses-development-in-china-expedited/2009659.article http://www.streetinsider.com/Corporate+News/Hydrogenics+(HYGS)+Enters+Fuel+Cell+Tech+Supply+Agreement+with+Several+Chinese+EV+Integrators/11075752.html You can keep making solar and wind farms meanwhile you add some hydrogen stations at different locations, you will needed anyway for the new cars that are arriving (that is why all car companies are rushing to get their h2 car). Everytime you have an excess of energy, you make hydrogen. Then you can inject that hydrogen in the natural gas net, or sale it for vehicles or make fertilizers. That would continue until your minimun renewable output will match with all your electricity requirements, so all the extra energy you convert it in fuel for all kind of vehicles and transport. There is not need to storage electricity with other methods to convert again to electricity.

Something that is much much worse than a movie breaking physics laws or logic, is an audience criticizing the things that in fact are correct but they were too blind to not notice it or at least try to imagine a scenario where it can work.

thank you very much kunok!! I imagine that was something related to the speed of sound, but I could not find nothing in my previous search on google. But I guess I was using the wrong keywords. Have a nice day.

I show the links and I provide more math here: The thing is that like radiation follows the inverse square rule, each time you get close to the sun, the power by m2 increase a lot, so with that power over a very light sail, the acceleration you get is close to 4000g. That is why you need to imprint the instruments in the sail itself, bidimensional bodies does not get affected by huge accelerations (in case you can kept that constant in the whole area). Of course accomplish that is super difficult, but the development to that point is very cheap. We would be able to make the first graphene quarter wave sails (or something similar) in 10 years, from that point you can launch some and start practicing to see how much close you can get, starting from 0.3au periapsis to 0.007au which is your goal. This might take 30 or 40 years more from that point. But the good news is that these sails would be very cheap, you dont even need higher area sails to test this, the power-mass ratio is the same. If you try to make a conventional interstellar probe using fusion or other technology, its mass will be huge, thousands of tons, and we know almost nothing from the interstellar medium, what if we lose it? With the sails you can sent a lot. Other methods like a huge particle accelerator or something similar had their issues too, first you need higher accelerations if you dont want to increase to the infinite the cost of your accelerator. You can not brake on destination. A solar sail if accomplish to brake in destination, it can explore the whole star system with all its planets.

Physics problem: If I have a long rope in tension, lets said 2000m. If I pull one extremity of the rope, how much time it will take the pull force to reach the end? This is the same than waves? Where the tension force is the one that dictates the speed of the wave? This has something to do with the material used in the rope?

I will call on skylon too, but is too soon. dragonv2 at least is at half way.

Solar sails probes with the science instrument imprinted in the same sail, using graphene or CNT with quarter wave holes in the sail, you can make a surface reflecting with almost no mass. The same sail works also as parabolic to help in the laser communications, in a close diving by the sun, you can reach 7% the speed of light and you can brake using the same method when you reach the star destination. The sail would be cheap to make so you would not waste a lot of money until you get it. Once you get it you can sent more than one and at many stars. Even higher speeds can be achieve it if you reduce your diving distance in the apogee. Superconductor "weights" can move over magnetic veins on the sail to equal loads and shape.

I took that friction value from a table of different type of surfaces, and I choose gravel and dust, but one thing that I dint notice then is the value is measure at 40% of humidity that we have on earth, if we dry that dust and gravel to mars levels, the friction coefficient will reduce by 40%, then we need to add the temperature which any trace of water it becomes in ice dust. This is also why NASA said is too easy to drill on mars, because the friction coefficient is very low. Also if you look the friction angle on mars for all different rovers and surfaces measure it, you find values between 14 degress to 40 degress! http://onlinelibrary.wiley.com/doi/10.1029/2010JE003625/pdf Page 36 of 38 In addiction, the fact that we never measure 400kmh in mars means nothing, I never saw winds higher than 130kmh in my decades of living, but I know that are circustances and places where you can have 500kmh, besides you dont need a storm with constant winds of 400kmh, there is something called gusts or twisters generated when 2 front of winds collide that can produce 400kmh winds over a short time scale. For finish, if you walk under a storm with almost not visibility, you will not have a constant friction force in your boots because the terrain is not regular. But well, maybe your purpose is just negate anything that I said because is easier than admit that can happen :S Yes, looks like a childish behavior. Is explained above.

Guess what? It seems that we are even further than the 178th century according to your scale. In my example of 100m building, I imagine the motor has close to 20hp, at that power any motor has 93% of efficiency. Also any motor is a generator.. Just turn a DC motor and touch the cables and see what happen , or connect a generator to power. The only thing that can reduce efficiency (which I am not sure) is the pump pressure disk that push the water if is designed in a way that in reverse would not catch much water. I will later search that in google if I have time. But today we have even better electrical engines that can reach 98% of efficiency even at low power scale, and I am not talking about superconductor motors. http://www.enstroj.si/Electric-products/emrax-motorsgenerators.html " EMRAX motor is a completely new type of pancake axial flux brushless synchronous three phase AC (Alternating Current) electric motor. It can also work as a generator - technical data are the same - either EMRAX is used as a motor or as a generator. We achieved our objective and built a high-powered, high torque, extremely light, direct drive, low noise electric motor, which efficiency is up to 98%. Because of the high torque EMRAX engine can achieve high power also at relatively low rotation speeds. " I did many calculations on pipe pressure loses before. So I have a very good idea on the effect of long pipes, curves, "T" and different type of faucet. Independent of how the house-building design is made, you will find a section between the pump and the main tank without many obstructions and a good diameter, so the flow almost not change. One of my friend´s house has a terrible pipe design, and even there the lost of load from a boost pump (not higher tank) to the worst place of the house was not more than 30%.