Description: 外海王星天體（TNOs）是一類在海王星軌道之外繞太陽運行的小天體和矮行星。這些天體的定義是：與太陽的典型距離（其軌道的半長軸）大於海王星與太陽的典型距離（30.1 個天文單位或日地距離）。目前已知的 TNO 超過 2000 個。大多數是柯伊伯帶的成員，但更遙遠的天體則是被稱為分散盤的天體群的成員。

Related Terms:

• 天文單位
• 矮行星
• 柯伊伯帶
• Neptune
• 太陽系
• 半長軸

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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