Description: 恆星的內在亮度取決於其溫度和物理大小。溫度越高、體積越大的恆星越亮。光譜類型是根據恆星光譜的特徵進行分類。這大致反映了溫度的變化。光度等級則是根據恆星與同光譜類型的其他恆星相比的亮度來分類。光度等級用羅馬數字表示：主序上燃燒氫的恆星被劃分為矮星（V）。例如，太陽的分類是 G2 V。在它們之上（隨著大小和亮度增加）依次是亞巨星（IV）、巨星（III）、亮巨星（II）和超巨星（Ib代表亮度較低，Ia代表亮度最高）。所有這些類型的恆星都是演化了的恆星，其內核中的氫已經燃燒殆盡。貧金屬亞矮星是金屬含量較低的氫燃燒恆星，位於主序以下。最後，白矮星（恆星殘骸）則位於主序更下方。

Related Terms:

• 矮星
• 巨星
• 赫羅圖
• 光譜類型
• 超巨星
• Subdwarf Star
• 亞巨星

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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