处理X星在天空中醒目地戏剧性地出现，第二个太阳现象偶尔会在日出或日落时呈现给观测者这件事对NASA来说意味着什么？
And how does NASA mean to deal with a dramatic appearance of Planet X in the skies, for all to see, the Second sun phenomena that on occasion presents itself to observers at sunrise or sunset.
他准确地预测了金星将在1761年和1769年穿过太阳表面——尽管他没能活到看到这一现象的那一天。
He accurately predicted that Venus would cross the face of the Sun in both 1761 and 1769—though he didn't survive to see either.
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。
In November 1677, Halley observed a transit of the innermost planet, Mercury, from the desolate island of St Helena in the South Pacific.
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