Description: 外海王星天体（TNOs）是一类在海王星轨道之外绕太阳运行的小天体和矮行星。这些天体的定义是：与太阳的典型距离（其轨道的半长轴）大于海王星与太阳的典型距离（30.1 个天文单位或日地距离）。目前已知的 TNO 超过 2000 个。大多数是柯伊伯带的成员，但更遥远的天体则是被称为分散盘的天体群的成员。

Related Terms:

• 天文单位
• 矮行星
• 柯伊伯带
• Neptune
• 太阳系
• 半长轴

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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