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KerikBalm

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  1. Argon has a MW of 40 N2 has a MW of 28..... CO2 has a MW of 44... What were you saying?
  2. That was assuming an average temperature of -40C, assumes even temperature distribution - the rate of loss when its warmer will not be compensated by the reduced rate when it is colder, and of course, ignores the solar wind - which admittedly is hard to model. It also assumes the gas is never significantly disassociated into smaller compounds. Anyway... it lacks nitrogen now... where do you propose getting enough to rebuild Mar's atmosphere? -Although you could stubstitute Argon/Krypton/Xenon for a lot of N2, to truly terraform, it needs to have a N2 atmosphere so that life can fix nitrogen.
  3. I seem to recall some challenge to make the lightest eve lander ended up with something like a 2 stage to orbit vehicle. The first stage was an ion powered plane, and the 2nd stage was a landercan with I think a FL-T200 tank and a 48-7s.. maybe it was more stages than that... but I think if it was, it could probably be adapted to 2 stage. Well, with that thick atmosphere, you don't need to go very fast, so it should be able to get you up out of most of the soup, no? On another note: NEAR/FAR - how hard is it to get off eve with that mod? Ignoring gravity and atmospheric drag, you only need a dV of ~3.5km/s With NEAR/FAR, as long as your lander isn't pancake shaped, and has a decent TWR, you should be able to get into orbit with a dV of much less than 12km/s, no? 6km/s? that should be feasible in a single stage...
  4. Pure CO2 is not a terraformed atmosphere. Escape valocity for mars is 5.03 km/sec That is less than half that of Earth's 11.18 km/sec Which means the KE of the gas molecules before they start to reach escape velocity at a high rate can only be must be 1/4th of that of Earth. Its orbit is at about 1.5 AU, meaning it gets just under half the sunlight of Earh.... Half the energy input, but the gas needs 1/4 the energy to prevent escape. Also note that CO2 has a much higher MW than N2 -> 44 vs 28 Its also much higher than that of H2O -> 18 The average velocity of the speed of the gas molecules will be: http://en.wikipedia.org/wiki/Root-mean-square_speed Of course, that is the average, and the closer that is to the escape velocity, the more you will have that actualy acheive escape velocity. Lighter gas molecules are more easily lost. You bring up Venus, with its atmosphere of heavy CO2 with a MW of 44, which almost completely lacks water vapor. Its atmosphere is severely deficient in hydrogen containing compounds. Note that a thick atmosphere can help retain lighter gases, much like volatile compounds will evaporate slower when they are in a solution. Any N2 that reaches escape velocity will likely impact another gas molecule before escaping, and slow down again. As nitrogen is only ~3.5% of the atmosphere, its rate of loss is much slower than it would be if the CO2 wasn't there. Earth's mainly nitrogen, argon, oxygen, and H2O atmosphere wouldn't last long on Venus, and it wouldn't last long at Mars, particularly if you warmed mars up to Earthlike temperatures. (Athough, with massive mirrors blocking the sun on Venus, and a magnetic field to help retain the hydrogen that is produced by the suns rays splitting water, venus could hold on to an earth like atmosphere, but again with oceans, and without blocking much of the sun, it would again have a runaway greenhouse) High CO2 concentrations to warm it and reduce the loss of other gasses would render the atmosphere unbreathable, long term exposure to CO2 above about 5% begins to be toxic to humans. Warm temperatures with relatively light gasses requires a pretty large escape velocity. Titan retains N2 because its so cold... that gas would all escape if it was warmed up to something like 10C. Mars wouldn't lose its atmosphere as fast, but it would. The lack of a magnetic field would cause it to lose hydrogen faster.
  5. Nothing says you can't launch multiple rockets in the same launch window.... so you don't need big expensive rockets, you could get away with many cheap rockets, that are cumulatively expensive. Mars colonization probably won't happen, but its still a far more interesting and accessible planet than any others (though jupiter and saturn have quite a few interesting bodies in orbit around them, the planets themselves are pretty inaccessible -> descend through clouds into the abyss - > end of mission)
  6. Low population density means the zombie horders wouldn't get that large (can't have more zombies than you had people). Military forces of the day were geared towards close range combat, thus well prepared to hack up zombies without being bitten. Military preparations of the day had a lot of preparations for withstanding seiges. Zombies would have a very hard time penetrating a castle. Less zombies, slower zombie spread, more armor agaisnt bites, more defensive works, and men that know how to use melee weapons. They'd be fine.
  7. The very large tanks are fine IMO, given that you normally only use them when you haev a large payload, and thus the mass fraction doesn't change al that much (as tank weight in the lower stage is minor)... but the small ones... are quite bad, I loathe using anything smaller than the FL-T100. And it wasn't noted, but the mass ratio of the tanks for Xenon is pretty bad too (and the propellant cost is obscene!)
  8. Mars lacks the mass to maintain an atmosphere and warm core. The suns output has increased (warmer temperatures= faster atmosphere loss), and it would lose its atmosphere even faster now that its got no magnetic field, and the outgassing from its mantle has stopped. For the effort and resources to terraform mars (temporarily, its obvious that it had liquid water in the past, implying an atmospheric pressure and temperatureabove the triple point), we could probably have truly spacefaring civilization - asteroid colonies and such. Then we could spread to the majority of nearby star systems if we don't need a habitable planet to settle on. That said... if we were going to terraform a planet... lets look at the list (this is a little like the beginning of War of the Worlds from the 1950s, except not omitting Venus which they still hadn't gotten the public to understand the hellish conditions, and more up to date) Mercury: LOL, nope Venus: LOL, nope - some may say it wouldn't be so bad if you thinned out the atmosphere, but it has a severe lack of the element hydrogen (no water), an incredibly long day, and still very intense solar radiation that would cause a runaway greenhouse again in short order if you somehow managed to get it to have oceans of liquid water. It may have been habitable with oceans 4 billion years ago, but current hellish conditions have erased most evidence and make it too difficult to go look for more subtle evidence. Earth - home sweet home, lets not f*** it up -Earth's moon: LOL, nope, not enough gravity to hold on to an atmosphere, to easily wiped out by the same sort of calamity that may affect Earth. Mars - probably not worth the effort, but closest so far: in the Hellas basin the atmosphere gets just thick enough to allow liquid water to exist (temporarily, in theory). The day is similar, it has enough gravity to hold on to a breathable atmosphere for a limited amount of time (a millenia or two perhaps much more). Current temperatures sometimes get into the comfortable range (but with such a thin atmosphere, the temperature swings can be pretty wide, from a veyr warm 35C, to -120 C). Clouds of water ice on occassion, the Phoenix lander appears to have imaged a salty brine on its landing legs (liquid salt water perhaps). It contains clear signs of being habitable once. Jupiter: LOL, nope - Its moons: LOL, nope to terraforming, none could hold an atmosphere, nor would they receive enough light, nor is the surface radiation anywhere close to healthy... underground colonies may be feasible on Europa/Ganymede/Callisto. Saturn: LOL, Nope - Its moons: LOL, nope to terraforming, none could hold an atmosphere at 25C, nor would they receive enough light, nor is the surface radiation healthy... underground colonies may be feasible. Titan would be interesting, as the atmospheric pressure is survivable (though the temperature is not). Its mainly nitrogen, so it wouldn't be too toxic to breath if you warmed it up and had supplemental oxygen, so surface colonies may be feasible, and if there is a hole, it wouldn't be as bad as a hole in a colony exposed to a vacuum... Uranus: LOL nope -Its moons: underground colonies may be feasible (but these would be little different than asteroid colonies) Neptune: See above.
  9. I invented a new number, It's going to be called the GrahGOOOAAAAAALLLLLLLLLLL. Its graham's number to the power of Graham's number. I await the publication of this number in a math journal. Ummm I don't think he did that, or he wouldn't be asking "how do i describe it in math? " and "i want to know how to write that down without losing my sanity."
  10. Considering I've seen one (of only 2 - 46-0524 at the SAC museum) with my own eyes, no, I do not find that worrying at all.
  11. The only flying aircraft carriers that even came close to working: http://en.wikipedia.org/wiki/USS_Akron_%28ZRS-4%29 http://en.wikipedia.org/wiki/USS_Macon_%28ZRS-5%29 ^the hangar for this thing remained long after it was gone, and it was very close to where I grew up, I saw it very often. Also of note: http://en.wikipedia.org/wiki/FICON_project http://en.wikipedia.org/wiki/McDonnell_XF-85_Goblin
  12. Yes, I do that, and it doesn't work. Say I want to hold a pitch of 40 degrees, I pitch up to 40, hold it there a moment, tap "F" The nose drops a bit, and SAS begins to apply a pitch correction, but it starts doing it too slowly, and the pitch continues to drop a bit... then the SAS decides to stop trying to hold the heading I set, and to set a new one at a lower pitch, often it will just have the pitch slowly drop for a while in the white "SAS" light turns to those circular arrows, before finally locking in at a much lower pitch, which results in a near zero AoA, and the plane descends, so I have to babysit it the whole flight tapping the pitch up key.... Meanwhile, it often won't reset when I enter control inputs, like when I'm turning or trying to correct a roll, so after I tap roll or yaw, it often undoes it... so I just fly the whole darn way manually. And it can get quite annoying having to manage action groups for intakes, and engine toggles and rapier switches, all while flying manually or with an SAS the won't hold a heading. Its particularly bad in one plane I have with a rapier cluster that overheats, so I have to tap the engine toggle pretty often (or yes, I could lower the thrust limiters... but I want full power on takeoff, particularly when carrying a full payload... and trying to fly manually while clicking on each engine to change the thrust limiter whith a really bad framerate is... well, not feasible) This SAS behavior has been bugging me for a while... but trying FAR has just made it too annoying to not mention. on another note, I wish we had a SAS setting that acted like SAS did in .18 when you had no ASAS module... it just stops rotation, and doesn't try to return to a given heading... I loved that SAS behavior with landers. As I metioned earlier, the way SAS "fights" you unless you tap F after every keystroke (and often I have to hold F... but thats probably a result of the game running slow with very largeships), is also quite annoying, and this is true not just for planes, but also landers. Are there any good mods out there to replace the stock SAS? I'm quite fed up with it.
  13. I know about aircraft design. My question is very simple HOW DO I STOP THE SAS FROM RESETTING ITSELF? That is all I want to know.
  14. SAS is freaking useless in the atmosphere with FAR installed... I have to fly everything completely manually, which is a major pain with "15 minute" ascents that take more like an hour due ot reduced frame rate, and 2 hours due to the need for quick loading....
  15. I think we're more like the romulans and ferengi
  16. NEAR, or a modified FAR Radial drogue chutes Better information display in SPH/VAB (at least display ship mass like in map view, even if it doesn't reach the level of Kerbal engineer) Larger sized landing gear and cargobays (Really really easy to do, I just duplicate the .cfg file, set a rescale factor >1, and then tweak stats accordingly). Ducted electric fans/propellors for exploration of atmospheres without oxygen. Air Augmented rockets (ISP gets worse with increasing atmospheric pressure)
  17. Well, this is sort of a generic problem I run into with many designs... its not an issue in space, but the SAS really annoys me in the atmosphere. Maybe it is NEAR/FAR specific. In a more mild form for many craft, I have a problem of getting the SAS to lock into a heading. For example, I raise the nose to 45, although my heading is only 35 (AoA of 10)... and toggle SAS (tap the F key). Instead of locking it in place, the nose drops as the SAS starts to give a small pitch input... but rather than increasing the pitch response to bring it back up, the white "SAS" light turns to those circular arrows, and the nose will slowsly drop for a while, before the SAS finnaly locks into a heading. Basically, it seems when the heading deviates from the null setting by a certain amount, SAS automatically resets the null... I'm asking if there is anyway to stop this SAS behavior.
  18. I've been having a lot of problems with SAS not being able to hold a heading when using NEAR or FAR. SAS tends to over correct when in atmospheric flight a little, resulting in a small oscilation... but when the oscilation gets just big enough, the SAS null point resets a little... and the result is I basically have to fly manually. Is there any way to tweak this? I'd really like to make it so SAS never resets its null point unless I toggle it - is there any way to do this? It is really really really *expletive deleted* annoying when SAS auto-resets the heading its trying to hold
  19. Akinator was unable to guess Dr. Reid from Warzone 2100 You just got to have an obscure enough character, and then not help it learn at the end
  20. http://en.wikipedia.org/wiki/Far-Seer Its basically the story of dinosaurs on Laythe... Some "preserver" entity transports dinosaurs to a water world tidally locked to a gas giant before the extinction event on Earth. They develop into an intelligent civilization The water world is tidally locked, and the main landmass does not face the gas giant. Eventually, ships sailing beyond the horizon spot the gas giant, which they deem the face of god, and a new religion starts. Thats the backstory Book 1 is essentially a rehashing of Gallileo and the persecution by the church.... that's not the face of god, its a planet that their world orbits - with the introduction of telescopes, they can see other worlds with moons. In a sort of break from real good physics... planetary rings form when a moon gets too close and breaks up, and the same fate awaits their world. Book 2 is a rehash of darwins voyages, with some other stuff in there Book 3 involves an ancient alien space elevator (extending to the lagrange point... since the world is tidally locked, after all), population problems, and first contact with a race of dinosaurs on another continent (columbus sort of?)
  21. Even if we could produce that much antimatter... see my previous post.... Why bother with an acceleration beyond 1g? If we have that sort of technology, surely cryostasis or just increased longevity or some form of hibernation would be better. Its more energy efficient, the dry mass can be lower due to reduced need for life support and no water filled tanks. Going at .95 or .9995c wont make much of a difference to those not on the ship. If you can make those on the ship able to handle longer voyages, then why not crank the thrust back and take it a little slower?
  22. It could not guess Afsan, from the Farseer books. It "learns" by asking you to name the character when it can't guess it
  23. They go to orbit first to reduce lost dV due to gravity drag. It is more efficient to burn perpendicular to the force of gravity, than opposing it
  24. Actually, the most efficient way to get into an 80 km orbit, is to go into an 80x80 orbit directly. Or a 80x70km orbit, and then burn at apoapsis to turn it to 80x80. Just like any other hohman transfer. For practical purposes, just split burn pointing at the horizon until your PE is at 70km (use a maneuver node so its half before, and half after apoapsis). If your apoapsis goes up a little more than you'd like, a tiny burn at PE should fix that (or even only raise your PE to 65-68km depending on how much over 80 you went). Once in a nearly 70x80km orbit, it should be trivial to circularize to 80 x 80km
  25. I should have explicitely mentioned the KE equation, 1/2 MV^2 Basically, if you're pushing your working mass to twice the velocity, you need 4x the energy. Its like the opposite of a rocket In the air, you can use the air as essentially unlimited working/reaction mass, and you are limited by energy. You actually want to push the air as slowly as possible to generate the needed thrust. In a vacuum, when you are using solar power, or nuclear power, you aren't so much limited by energy, but you are limited by reaction mass (I'll ignore the chemical situation for now). As a result, you want to push your reaction mass as fast as possible. Wings allow you to generate a lot of "thrust" perpendicular to your direction of motion, for a small penalty to your KE. Also note, conservation of energy does apply here. Work done is equal to Force * distance -> of course that is force in the direction of motion. As the force is perpendicualr to the direction of motion (assuming perfect wings, and perfectly horizontal flight), then sin(0)=0, and no work is done. Just as when a 1kg weight sits on the floor, even though there is a constant 9.8 m/s/s force upon the weight sitting on the floor, no work is done, there is no change of energy. The same is true if this 1kq weight starts sliding along the floor (assume it is frictionless, or nearly so.. like a sled on ice, or really low friction wheels over a smooth surface) "sliding" through the air with wings isn't as efficient... the air is disturbed a bit, which means the craft is imparting energy to it as it travels through it... but if you take a sailplane weighing 300 kilos, gliding along for 20 minutes with a L/D of 60:1, compared to hovering on rocket thrust ... which one do you think disturbs the air more? Which one takes more energy? Wings get your "free" reaction mass by deflecting air. With free reaction mass, you can move the reaction mass much slower to produce the needed thrust, which gives you huge savings thanks to KE = 1/2 MV^2 In KSP, the wings L/D turns to crap at high speeds. So the benefit is mainly seen at lower speeds. Also, in KSP, the air breathing engines are already 16x more efficient than they should be, making the benefits of wings much smaller in comparison. In NEAR/FAR, the engines are not quite as OP'd (the ISP is still ridiculous, but the max speed, and particularly the TWR are reduced), and the wings properly produce lift proportional to the square of velocity. Lower TWR engines, and wings that produce more lift, with a general decrease in drag, favor winged craft much more than stock
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