Description: 恒星的宜居带是指恒星周围类地行星表面可以存在液态水的区域。如果地球离太阳更远，所有地表水都会冻结；如果离太阳更近，所有地表水都会沸腾蒸发。在这两种情况下，我们所知的生命都无法形成或存活。有时，宜居带的概念被扩展到包括金星这样的行星，因为金星具有失控温室效应，即使行星离太阳更远，液态水也可能存在。银河系宜居带是指银河系中适合能够诞育生命的行星系统生存的区域：在那里，较重的元素应该足够常见，类地行星由这些元素构成，而像超新星这样威胁生命的事件应该足够罕见。

需要注意的是，宜居带之外也可能存在宜居条件。例如，木星的卫星木卫二上可能存在宜居的地下海洋。

Related Terms:

• 天体生物学
• Extraterrestrial Life
• 温室效应
• Supernova
• Planetary System

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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