他还指出了，地球在近日点的速度要比它在远日点快，近日点离太阳比较近，远日点是距离太阳最远的地方。

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

根据Marsden的计算，这颗彗星会在3月18日过近日点。

According to Marsden's calculations, this comet reaches its closest point to the Sun (perihelion) on March 18th.

近点年是地球连续两次通过近日点之间的时间。

The anomalistic year is the time between successive transits of the Earth through the perihelion.

当地球从远日点运动到近日点时，地球辐射带向内收缩。

W hen the Earth moves from perihelion to aphelion, its radiation belts are expansion, and aphelion to perihelion contraction.

但这并不是简单的一件事情，因为近日点和远日点的日期都会变换。

But it's not that simple either, because the dates of the perihelion and aphelion are also shifting.