行星飞行 meaning in Chinese

interplanetary operation

The ability to do this will be necessary in future flights to distant planets
再将来向遥远地行星飞行时就需要有这样做的能力。
The american space probe , mariner 9 , has become the first spacecraft to orbit another planet , swinging into its planned trajectory around mars without a hitch
1971年的今天，美国宇宙飞船水手九号顺利进入火星的计划轨道飞行，成为首架环绕另一颗行星飞行的宇宙飞船。