Description: 當兩個天體在觀測者看來排成一條直線或接近一條直線，並且在天空中位於相反方向時，謂之為“沖”。觀測者並不需要能同時看到這兩個物體。例如，在滿月時，太陽、地球上的觀測者和月亮排成一線，因此月亮可見部分的表面完全被太陽照亮——除非三者完美對齊，在這種情況下會發生月食。當行星、彗星或小行星處於沖時，通常是指與太陽和地球上的觀測者的關係。當行星處於沖時，它將顯得特別明亮，在移動方向上出現“逆行”（因為地球在其較內側軌道上移動得更快），並且離地球特別近。

Related Terms:

• 合
• 月相
• 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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