尼古拉·哥白尼（1473－1543）是波兰数学家和天文学家。《天体运行论 》主要阐述了地动说的一些原理。比如，宇宙和大地都是球形的，天体以太阳为中心做匀速圆周运动，地球的运动由自转、公转和岁差三种运动构成，描述天体的位置有必要用到球面三角形等等。
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