Aphelion is the farthest orbital point from the sun and perihelion is the closest.

Aphelion（远日）是离太阳最远的轨道，Perihelion（日）是指最的。

The most distant point is known as aphelion and occurs around the 4th of July.

最远的被称为“远日”，大约出现在7月4日。

However, its motion around the Sun is faster at perihelion than aphelion.

然，它在日比在远日时公转更快。

Meanwhile, it's at its slowest in early July, at its furthest point from the Sun, or aphelion.

同时，它在 7 月初最慢，在离太阳最远的，或远日。

At aphelion, Mercury's spin is a bit faster than its orbital speed, so the Sun moves rapidly westward across the sky.

是在远日时，水星的自转速度会比它的公转速度稍快一，所以太阳会在天空中快速地向西移动。

The motion of Newton's comet at aphelion may be equally slight.

牛顿彗星在远日的运动可能同样轻微。

He also figured out the planet goes faster when it's at perihelion, nearer the sun, than when it's at aphelion, its furthest distance.

他还算出这个行星在距离太阳最的日比在距离太阳最远的远日时运动的速度快。

The tides from the Sun are far stronger on Mercury when it's at perihelion, the closest point in its orbit to the Sun, than when it's at aphelion, the farthest point in its orbit.

在日，也就是水星与太阳距离最处，它受到的来自太阳的引潮力比在远日(水星轨道上离太阳最远的)时要强烈得多。

The corresponding change in gravitational force causes the Earth to move fastest in January, when it reaches its closest point to the Sun, the perihelion, and the slowest in July, when it reaches its farthest point, the aphelion.

引力相应变化导致地球在一月达到日时运行最快，在七月到达远日时则最为缓慢。