但是它们的小尺寸也意味着它们缺少机载的推进系统，这就是为什么它们通常都固定在一个特殊的轨道。

But their small size also means they lack on-board propulsion systems, which is why they generally remain locked to a particular orbit.

youdao

但是它们的小尺寸也意味着它们缺少机载的推进系统，这就是为什么它们通常都固定在一个特殊的轨道。

But their small size also means they lack on-board propulsion systems, which is why they generally remain locked to a particular orbit.

youdao