Description: 约翰内斯-开普勒（Johannes Kepler）在 1600 年代初制定的三大定律首次认为行星的轨道并非完美的圆形。第一定律指出，行星以椭圆形围绕太阳运行，太阳位于其中一个焦点。第二定律指出，在轨道的给定时间间隔内，行星和太阳之间的直线所覆盖的面积是相同的。根据第三定律，行星绕太阳运动的时间（T²）的平方与其半长轴的立方成正比（a³，半长轴是一个长度，表征行星绕太阳轨道的大小）。开普勒通过研究他的导师第谷-布拉赫对火星轨道的观测发现了这三个定律。他利用这些定律对当时已知的行星轨道进行了最精确的计算。

Related Terms:

• 椭圆
• 轨道
• 行星
• 太阳系

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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