nutation in right ascension

例句：

1. 1. The planet's gravitational pull causes the stars to appear to move across the sky in a parallax effect.
   行星的引力作用导致星星在天空中以视差现象移动。
2. 2. The astronomers observed the star's movement through the telescope and noted the parallax effect.
   天文学家通过望远镜观察那颗星的运动，并注意到了视差效应。
3. 3. The observers were able to measure the parallax angle accurately, which helped them determine the distance of the distantobject.
   观察者能够准确地测量视差角，这有助于他们确定远处物体的距离。