Once in space, ion engines steadily propel a spacecraft until it travels faster than it would have using a chemical rocket.
一旦进入太空，离子发动机将稳步推进航天器，最终达到的速度会比使用普通火箭的更高。
2
The exhaust velocity, though, is enormous—more than ten times that of a chemical rocket—and this makes ion propulsion extremely efficient.
但其排气速度却异常惊人，大约为化学燃料火箭的十倍—这使得离子推进器的效率非常高。
3
The push power be produced is very tiny but the key point is that compare to produce same push power ion propulsion needs lesser fuels than traditional rocket.