Description: 伽利略衛星是圍繞木星運行的四顆最大、最明亮的衛星：木衛一（Io, 艾奧）、木衛二（Europa, 歐羅巴）、木衛三（Ganymede, 加尼美得）和木衛四（Callisto, 卡利斯托）。離木星最近的是木衛一，它有數百座活火山。木衛一火山爆發的主要原因是受到木星引力潮汐效應的 "揉捏"。木衛二的整個表面都被冰覆蓋著。據信，冰層下是液態水海洋，是太陽系除地球外能夠孕育生命的最佳候選者之一。木衛三是太陽系中體積最大的衛星，也是質量最大的，是月球質量的兩倍。木衛四的大小幾乎與水星完全一致，但質量只有水星的三分之一。

這四顆伽利略衛星是伽利略-伽利萊（Galileo Galilei）於 1610 年發現的，是伽利萊使用望遠鏡進行天文觀測的開創性活動中的若干發現之一。伽利萊通過記錄發現，隨著時間的推移，四顆衛星圍繞木星運行，就像一個微型太陽系。這清楚地表明，天體可以圍繞地球以外的中心運行；這一觀測結果在科學界對太陽系的認知轉變過程中發揮了重要作用，從以地球為中心（地心說）轉為以太陽為中心（日心說）。

Related Terms:

• 木衛一，音譯為艾奧
• 木星
• 衛星
• 潮汐鎖定

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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