Description: 約翰內斯-開普勒（Johannes Kepler）在 1600 年代初制定的三大定律首次認為行星的軌道並非完美的圓形。第一定律指出，行星以橢圓形圍繞太陽運行，太陽位於其中一個焦點。第二定律指出，在軌道的給定時間間隔內，行星和太陽之間的直線所覆蓋的面積是相同的。根據第三定律，行星繞太陽運動的時間（T²）的平方與其半長軸的立方成正比（a³，半長軸是一個長度，表徵行星繞太陽軌道的大小）。開普勒通過研究他的導師第谷-布拉赫對火星軌道的觀測發現了這三個定律。他利用這些定律對當時已知的行星軌道進行了最精確的計算。

Related Terms:

• 橢圓
• 軌道
• 行星
• 太陽系

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This is an automated transliteration of the simplified Chinese translation of this term

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