View Single Post
Old 2007-10-08, 16:20   Link #112
edf91
Senior Member
 
 
Join Date: Dec 2003
Quote:
Originally Posted by 4Tran View Post
"Turning" is a very ambiguous term to use since it means one thing in terrestrial environments and something quite different in space. The most efficient way to do it in space is to first rotate one's heading and then apply full thrust in the vector you're aiming for.

Centripetal force does exist. However, it has no effect when it comes to changing a space vehicle's facing. (I've really got to stop using the word "turn")

Not quite. A vernier can only generate a small portion of a vehicle's total thrust. It'd be more efficient to rotate first, then apply all the thrusters. And since any off-center thrust can generate rotation, there isn't really any need for dedicated verniers for that purpose. Applying a 1g acceleration to a 18m vehicle, for both thrust and counter-thrust, can finish a 180-degree heading change in less than half a second.
I think the main problem I having with your explanation (which make sense, btw) is this - if it is so easy to change direction in space, provided you have acceleration, why is almost all science fiction with big rocks falling in space, it is nearly impossible to move them out of earth's way? If it's all about acceleration, just hook up jet engine to the rock, turn and off you go...

Quote:
Originally Posted by 4Tran View Post
Then why would the thrusters have to be postion on a space vehicle the way they are on a missile? As long as they can all be pointed in the same direction, they'd still generate the same amount of thrust.
I think this is just a misunderstanding - I am basically just calling the thruster configuration in which they all face the same direction and you cannot really move them as the "missile" configuration, since it is the most obvious example I can think of. MS, in most cases, have supplement thrusters on its feet so it can face in another direction, and it's something a missile cannot really do, so it can move in another direction without having to move its main thrusters to redirect itself.

Quote:
Originally Posted by 4Tran View Post
What difference would that make? We already know that the Gundam creators weren't trying for realism to begin with. Sure a few elements were pretty good, but the bulk of it is strictly fantasy. The only thing that they managed to do was to deceive some of the audience.
I know, but you are making it like a "all or nothing" system - meaning I have to completely give up all common sense in order to watch a series like Gundam, and that I cannot just accept some aspects of the show that might go against my knowledge? Usually a show has to give us some sort of reason/explanation before we can suspend some of our belief system, and I think Gundam in general did a pretty good job of trying to offer some sort of explanation. Wouldn't you agree that it's easier for viewers to "believe" in a show if it doesn't have too much stuff that go against our beliefs?
edf91 is offline   Reply With Quote