And as it does, from Earth's perspective, distant stars appear to move their positions relative to the sun.

从地球的角度来看，遥远的恒星似乎在相对于太阳移动它们的位置。

They therefore change their apparent position relative to other stars.

因此，它们改变了相对于其他恒星的表观位置。

Mercury the planet moves pretty quickly, visibly changing its position relative to the background stars even after a single night.

水星的移动速度非常快，甚至一个晚上就可以看到它和背景星系的相对位置发生了明显的变化。

You got polar orbiting satellites, which stay in the same position relative to the sun as the earth rotates underneath them.

一种是极地轨道卫星，当地球在它们下面旋转时，它们相对于太阳保持在相同的位置。

They sailed by noting their position relative to a succession of recognisable landmarks.

他们通过注意相对于一系列可识别地标的位置来航行。

M depends on things like the size and shape of the coils, and how they're positioned relative to each other.

M 取决于线圈的大小和形状等因素，以及 它们是如何相对于彼此定位的。

However, there's a trick: consider the relative position and velocity of the two bodies with respect to the center of gravity of the system.

然而，有一个技巧：考虑两个物体相对于系统重心的相对位置和速度。

You can see it for yourself by doing the thumb thing: as you blink one eye and then the other, your thumb appears to shift position relative to more distant objects.

你先闭上一只眼睛，在换一边眼睛闭上，就会发现你的拇指似乎会朝相对于它远一些的物体移动位置。

So to us, on Earth, the planets go around the sky over the course of a year, and they also appear to change their positions relative to the Sun and the stars.

所以对我们在地球上的人来说，行星每年在天空中运动，看起来就像是改变了它们与太阳和其它星星的相对位置。