Description: 氫是宇宙中含量最多、重量最輕的元素；它只有一個質子，因此它的核電荷最小。當氫原子被激發時，例如被附近熱恆星的輻射激發，它們會在光譜的特徵區域產生譜線。這些氫發射線可用於探測氫原子：特別是氫α線，其濃郁的紅色使氫雲在天文圖像中呈現出絢麗的紅色；21 釐米（cm）氫線可用於利用射電望遠鏡探測大型氣體雲的結構。

Related Terms:

• 質子

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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