Description: 氢是宇宙中含量最多、重量最轻的元素；它只有一个质子，因此它的核电荷最小。当氢原子被激发时，例如被附近热恒星的辐射激发，它们会在光谱的特征区域产生谱线。这些氢发射线可用于探测氢原子：特别是氢α线，其浓郁的红色使氢云在天文图像中呈现出绚丽的红色；21 厘米（cm）氢线可用于利用射电望远镜探测大型气体云的结构。

Related Terms:

• 质子

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

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