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Events:
虞喜发现岁差
Country:
中国
Dynasty:
东晋
Chinese Era:
晋成帝司马衍咸和五年
Type of Event: Hot spot
Date:
330 AD
Where: 中国
Event Details:
咸和五年(330),晋天文学家虞喜发现岁差。岁差是指地轴运动引起春分点向西缓慢运行而使
回归
年比恒星年短的现象。虞喜认为“通而计之,未盈百载,所差二度”,从而得出五十年差一度的结论,这个看法居世界领先,较为精确,并使我国的历法比较早地区分了恒星年与太阳年。
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中国
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