observer's meridian

1. In most cases, the satellite will rise in the west, cross the observer's meridian, and set in the east, although satellites in a polar orbit can rise or set in any part of the sky!
   大多数情况下，人造卫星自观测者的西方升起，经过中天，然后在东方落下，虽然越极轨道人造卫星可以在天空的任意部分升起和落下！
2. The angular distance along the celestial equator from the observer's meridian to the hour circle of a given celestial body.
   从观测者所在的子午线到给定天体的子午线沿着天赤道的角距离。

noun

1. a meridian that passes through the observer's zenith