And that would mean the Earth's natural satellite may have always been too dry to host life.
这意味着月球这颗地球的的天然卫星可能由于过于干燥而无法存在生命。
2
One such cost arises when a satellite has to take evasive action and thereby USES up fuel, reducing its life in orbit.
当一个卫星不得不回避时，这一费用上涨了，因此也会用尽燃料，减少在轨道里停留的时间。
3
The propulsion subsystem is essential for maneuvering the MUOS satellite during transfer orbit to its final location as well as conducting on-orbit repositioning maneuvers throughout its mission life.