Glossary term: 年
Description: 一年是地球繞太陽一週的時間，但 "繞行一週 "有多種定義。太陽從一年到下一年出現在天空中完全相同位置的時間是一個回歸年，也稱為太陽年，約為 365.24 天。以遙遠的恆星為參照物，地球完成一個軌道所需的時間是一個恆星年。兩者之間的差異約為 20 分鐘（恆星年稍長），這是由於地球自轉軸的偏移造成的，即地球自轉軸在空間中非常緩慢地改變其方向。此外還有近點年：在橢圓軌道上，地球與太陽的距離時近時遠。近點年是隨後兩次最接近太陽（"經過近日點"）之間的時間差。對於太陽系內外的其他行星，其 "年 "的定義與這些行星圍繞太陽或其他中心恆星的軌道類似。
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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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