is the ion engine better than the rocket engine?

Question

i heard the the ion engine is slow but last long before running out of fuel and the rocket engine blast off at top speeds but last only in a few seconds or minutes depending on the fuel tank

Answer 1

A good question is - why hasn't 11 dimensional string theory led to any breakthroughs in physics?

Also, with a lot more computing power available, why hasn't there been any breakthroughs in new rocket engines?

To answer your question, ion engines are high efficiency and low thrust, regular rocket engines are high thrust and low efficiency.

Answer 2

the ion engine IS a rocket engine! ;-)

you must mean, "than a combustion rocket engine"

better varies. The ion engine has low thrust so cannot be used to take off from Earth, or to make big changes in trajectory, for example. But the ion engine uses much less fuel and can take you to high(er) speeds because of the small but very long lasting acceleration.

in some ways a spaceship with an ion engine is a bit like a supertanker (boat): accelerates slowly, stops slowly, can only make very broad turns. And requires help from something else (tow boat) for special manoeuvers.

still, it seems pretty clear that in the current state of our technology, the ion engine is our best bet to go anywhere far. You could start from orbit, and you'd have secondary combustion engines to be used for when you'd be on a hurry to change trajectory.

hope this helps

Answer 3

You pretty much have it. Ion engines aren't powerful enough to launch something or make quick course changes. But they get a lot more push from a pound of fuel over long periods of time than a chemical rocket. They send the gas out the back at about 50,000 mph while chemical rockets only send exhaust at 5,000 mph or so.