ydoaPs Posted June 17, 2005 Author Share Posted June 17, 2005 that's how they work. equal and opposite reations. Link to comment Share on other sites More sharing options...
flyboy Posted June 17, 2005 Share Posted June 17, 2005 nooooo rockets to push it back into place Link to comment Share on other sites More sharing options...
ydoaPs Posted June 17, 2005 Author Share Posted June 17, 2005 kinda wasteful Link to comment Share on other sites More sharing options...
flyboy Posted June 17, 2005 Share Posted June 17, 2005 y would it be wassteful? ok then u station a huge mass driver on the moons surface that would hav to be more powerful than the space based one if we made these then we could launch probes and stuff deeper into space faster without waitiing months or years for them to reach jupitor or planets like that Link to comment Share on other sites More sharing options...
mmalluck Posted June 18, 2005 Share Posted June 18, 2005 Take all the rockets and fuel used to move your accelerator back into place and strap then to the ship instead. Ta da! No need for the mass driver. This will supply the same amount of thrust that our mass driver did, without the complexity of the mass driver. Yeah, launching stuff from the moon would be easier, but building a huge accelerator isn't cost effective. The cost of an ion engine is small. You need a gas to ionize and a high voltage source to ionize with. The amount of fuel used by an ion engine is miniscule compared to a standard rocket. Even if the weight of bringing your own fuel for an ion engine is prohibitve, there's no reason why you can't harvest some 'fuel' from a nebula your passing through. Just gather up whatever gasses are present and use them as your gas to ionize. Link to comment Share on other sites More sharing options...
flyboy Posted June 18, 2005 Share Posted June 18, 2005 u dont understand how fast a mass driver could propel these ships they would easily go faster thatn wimpy conventional rockets Link to comment Share on other sites More sharing options...
flyboy Posted June 18, 2005 Share Posted June 18, 2005 besides your thread is about huge particle accelerators which would be a mass driver not rockets or ion engines Link to comment Share on other sites More sharing options...
insane_alien Posted June 18, 2005 Share Posted June 18, 2005 umm we do realise and understand quite well how fast a mass driver could send a space ship. have you considered the gforces on the poor astronaughts that are being put through this mass driver. If its on the moon then when you get to a fast speed say >20km/s then the centrifugal effect is going to crush the astronaughts (assuming the mass driver is wrapped around the moon) the idea with just placing the rockets on the ship is a good one. Link to comment Share on other sites More sharing options...
flyboy Posted June 18, 2005 Share Posted June 18, 2005 g-forces in space dont affect people that much than they do on earth since it is weightless someone could be goin mach 12 and not even know it unless its like 30 gs or sumthin really high like that Link to comment Share on other sites More sharing options...
insane_alien Posted June 18, 2005 Share Posted June 18, 2005 human limit is about 12g max if it is sustained and gforces have nothing to do with speed just acceleration and they affect you just as much in space as on earth. i'm not meaning gravity its just that i hang around with a pilot regularly and if its to do with accelerations i use g-forces technically not right but force of habit. Link to comment Share on other sites More sharing options...
flyboy Posted June 19, 2005 Share Posted June 19, 2005 he doesnt fly around in in a weightless atmosphere does he? gravity is part of the acceleration u can go faster and endure more in space because u dont hav gravity acting on u to pull u back im not saying that som1 wouldnt be affected by it they can just endure more gs than usual on earth Link to comment Share on other sites More sharing options...
flyboy Posted June 19, 2005 Share Posted June 19, 2005 would it be possible to have a giant particle accelerator in orbit around the sun? find a nice' date=' big space(like between some of the farther planets) and have some strategically placed asteroids with powerful magnets orbit the sun. well, could it work?[/quote'] everthing in the solar system orbits around the sun Link to comment Share on other sites More sharing options...
ydoaPs Posted June 19, 2005 Author Share Posted June 19, 2005 not necesarily Link to comment Share on other sites More sharing options...
YT2095 Posted June 19, 2005 Share Posted June 19, 2005 not necesarily such as? can you name something inside the solar system that doesn`t? Link to comment Share on other sites More sharing options...
ydoaPs Posted June 19, 2005 Author Share Posted June 19, 2005 any giant asteroid that was dislodged from it's system and wafted over here just to pass through. Link to comment Share on other sites More sharing options...
YT2095 Posted June 19, 2005 Share Posted June 19, 2005 got ya I guess being Influenced by, doesn`t mean an Orbit necesarily. Cheers I forgot about those suckers, comets etc... Link to comment Share on other sites More sharing options...
Edward Posted June 20, 2005 Share Posted June 20, 2005 I like the idea of using a Mass driver wrapped around the moon to launch a space ship if it is going all the way arountd the moon then it doesent have to accelerate uber fast you could probily have it accelerate safely at over 1g and you could theoreticly have it accelerate to over 1/2 C. and then launch without problems the olny one I could think of is the ship pulling away from the center of the moon too much. How long would it take something to accelerate to 1/2 C at 1-2 g? Link to comment Share on other sites More sharing options...
mmalluck Posted June 20, 2005 Share Posted June 20, 2005 That's not too hard to do... acceleration is the derivative of velocity, which is the derivative of displacement. To go backwards we integrate. We'll say were starting at 0 displacement and velocity, when time = 0 Acceleration = dt(Velocity) = 9.8 m/s^2 Velocity = dt(displacement) = 9.8 m/s^2 *t and .5c = 1.499*10^8 m/s so 1.499*10^8 m/s = 9.8 m/s^2 * t seconds This yields t equal to 15,295,918 seconds or 177 days. Doesn't sound too shabby, but this is considering we're going in a straight line. With circling the moon or any other body, you're going to have to trade off some of your forward acceleration for centripetal acceleration. Just for fun lets see how much distance we'd travel while speeding up to .5c. Displacement = 9.8 m/s^2 * t^2. For t = 15,295,918, we travel 2,292,858,053,134,695.2 meters or 2.292 billion kilometers. This is roughly the distance from the Sun to Uranus (2.8 billion km). You wouldn't want to accelerate too much faster than a g or two with a human crew, but you could fling as unmanned spacecraft out there many times faster. A proerperly designed satellite could probably survive an acceleration of 20Gs or more. With that acceleration (196m/s^2) you'd get up to .5c in only 8.85 days. The real trick here is being able to supply enough force for the mass to continue to accelerate. Link to comment Share on other sites More sharing options...
greentea Posted June 20, 2005 Share Posted June 20, 2005 you seem to be forgetting that velocity is a vector, so changing direction is acceleration, as well. your idea works only on a straight line and getting to any speed of the order of c at 1-2g will take a looooooong way. Link to comment Share on other sites More sharing options...
mmalluck Posted June 20, 2005 Share Posted June 20, 2005 you seem to be forgetting that velocity is a vector, so changing direction is acceleration, as well. your idea works only on a straight line and getting to any speed of the order of c at 1-2g will take a looooooong way. Actually I mention that. This yields t equal to 15,295,918 seconds or 177 days. Doesn't sound too shabby, but this is considering we're going in a straight line. With circling the moon or any other body, you're going to have to trade off some of your forward acceleration for centripetal acceleration. Link to comment Share on other sites More sharing options...
Edward Posted June 20, 2005 Share Posted June 20, 2005 Cool thanks so 177 days? Link to comment Share on other sites More sharing options...
flyboy Posted June 20, 2005 Share Posted June 20, 2005 go to this site it will tell u everything u need to kno http://www.scienceforums.net/forums/newreply.php?do=newreply&noquote=1&p=179421 Link to comment Share on other sites More sharing options...
flyboy Posted June 20, 2005 Share Posted June 20, 2005 and guys most objects in space travel faster than 1 g how do u think we keep satalites and space stations to orbit around the earth? Link to comment Share on other sites More sharing options...
mmalluck Posted June 20, 2005 Share Posted June 20, 2005 1 g is not a velocity!!! It's an acceleration! I think that's where you're confused flyboy. A g = 9.8 m/s^2 which is the force equivalent to that of the earths gravity. If we accelerate with an acceleration of 1 g, our little astronauts will be forced against the back of the ship with a force the same as the earths gravity. That is to say, that if our astronaut stepped on a scale he would weigh the same as he does on earth. After one second we'd be traveling with a speed(velocity) of 9.8 m/s After two seconds we'd be traveling with a speed(velocity) of 19.6 m/s After three seconds we'd be traveling with a speed(velocity) of 29.4 m/s After four seconds we'd be traveling with a speed(velocity) of 32.9 m/s and so on.... If we start accelerating with an acceleration of 2 g (19.6 m/s^2) and our astronaut again steps on a scale, he would weigh twice as much as he does on earth. After one second we'd be traveling with a speed(velocity) of 19.6 m/s After two seconds we'd be traveling with a speed(velocity) of 39.2 m/s After three seconds we'd be traveling with a speed(velocity) of 58.8 m/s After four seconds we'd be traveling with a speed(velocity) of 78.4 m/s and so on.... If we accelerate too quickly and our astronaut will experience too many Gs and will be crushed by his own weight. It's true. I could be going million trillion quazillion billion m/s (excuse me while I rip a hole in the space-time continuum as I travel faster than light ) and it's true I wouldn't feel any thing, but if I try to speed up to that ludicrous speed in a second from a stand-still, I'd be squashed all over the inside of my spaceship. go to this site it will tell u everything u need to kno http://www.scienceforums.net/forums/newreply.php?do=newreply&noquote=1&p=179421 That's funny. Your link just goes back to this thread. Link to comment Share on other sites More sharing options...
flyboy Posted June 20, 2005 Share Posted June 20, 2005 oops wrong site Link to comment Share on other sites More sharing options...
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