On one hand, to be able to go from one direction in the sky to study such an object to another direction to study another object, and on the other hand to be able to maintain accurately the position in space.
一方面，能够从天空的一个方向去研究这样一个物体到另一个方向去研究另一个物体，另一方面能够在空间中准确地保持位置。
标签
Study
Position
Direction