Description: 褐矮星是一種既非恆星也非行星的天體，它的質量相較於恆星來說太小，但相較於行星來說又太大。恆星的能量來源是核心中的氫聚變。褐矮星的內部溫度太低，無法維持氫聚變。不過，褐矮星在其生命早期能夠短暫地進行氘聚變，氘是氫的一種較重形式。這種氘聚變被用來區分褐矮星和行星，但很難觀測到。褐矮星的質量通常在太陽質量的1.2%到8%之間（大約是木星質量的12到80倍），尺寸與木星大致相同。年輕褐矮星外部區域的溫度（有效溫度）與小質量恆星（紅矮星）相近，但由於缺乏內部熱源，它們會隨著年齡的增長而冷卻，有些會冷卻到幾百攝氏度。

Related Terms:

• 氫
• Hydrogen Fusion
• 木星
• Mass
• 行星
• 紅矮星
• 有效溫度
• Stellar Activity

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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