Epicycle
01
本轮, 次级圆形轨道
(astronomy) a secondary circular orbit embedded within a primary circular orbit
例子
In his astronomical work the Almagest, Ptolemy used a system of deferents and epicycles to explain the observed motions of planets across the night sky.
在他的天文著作《天文学大成》中，托勒密使用了均轮和本轮的系统来解释夜空中观测到的行星运动。
Copernicus disagreed with the Ptolemaic model adding unnecessary epicycles, believing instead that planets revolve in simpler circular orbits around the Sun.
哥白尼不同意托勒密模型添加不必要的本轮，而是认为行星围绕太阳以更简单的圆形轨道运行。
02
本轮, 次级圆
a small circle whose center moves around the circumference of a larger circle
例子
The concept of an epicycle allows for the modeling of complex periodic movements in geometry and astronomy.
本轮的概念允许在几何和天文学中模拟复杂的周期性运动。
The motion of a point on an epicycle can be described mathematically by combining the rotations of the smaller circle and the larger circle.
本轮上一点的移动可以通过结合小圆和大圆的旋转来数学描述。
