英语语法分析

Halley was aware that the AU was one of the most fundamental of all astronomical measurements.

哈雷知道，天文单位是所有天文学测量中最基本的。

Halley realised that Mercury was so far away that its parallax angle would be very difficult to determine.

哈雷意识到水星离地球如此之远，以至于很难确定它的视差角。

In November 1677, Halley observed a transit of the innermost planet, Mercury, from the desolate island of St Helena in the South Pacific.

1677年11月，哈雷在南太平洋荒凉的圣赫勒拿岛上观测到了水星（最靠近太阳的行星）的凌日现象。