Glossary term: 二至點
Description: 地軸並非垂直於地球圍繞太陽的軌道平面，而是與垂直方向呈23.4度的傾斜角。因此，在地球軌道的不同位置上，地軸與太陽視線之間的角度在一年內是不同的。這種現象的實際效果是，對於地球上的觀測者來說，太陽在一天中達到地平線上最高點的高度會隨時間而變化。北半球夏至，同時也是南半球的冬至，大約發生在6月21日，此時太陽在北半球的高度到達一年中的最高點，同時在南半球的高度則到達最低點。而南半球夏至，同時也是北半球的冬至，大約發生在12月21日，此時太陽在南半球的高度到達最高點，同時在北半球的高度則到達最低點。
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Term and definition status: The original definition of this term in English have been approved by a research astronomer and a teacher The translation of this term and its definition is still awaiting approval
This is an automated transliteration of the simplified Chinese translation of this term
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