Description: 從地球上的觀測者的角度來看，當兩個天體在天空中看起來非常接近時，它們被稱為處於合相（合）。合相不一定是肉眼可見的——例如，每當新月時，月亮和太陽近似在一條直線上，但在此時，我們看不到月亮，除非發生日食。在這種情況下，或者兩個天體非常接近（合）以至於一個天體看起來遮住另一個天體時，天文學家就會將其描述為凌日或食。

Related Terms:

• 日蝕
• 月相
• 衝
• 淩

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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