一个多月以前评论(Comment from over a month ago)

这只松鼠又跳到一天了吗？闰年之所以存在，是因为地球轨道和我们通常的年度计算略有不同步。地球绕太阳旋转需要365天、5小时、48分46秒。为了弥补这5个小时的额外时间，2月份每四年又有一天，一个闰日。这个概念可以追溯到古罗马人，在教皇格雷戈里十三世于1582年引入的格里高利历法中得到了完善。虽然这一天的目的是使我们的一年与太阳历保持一致，但它也可以作为一个额外的日子来为春天做准备。
原文：
Has this squirrel jumped into another day? The reason why leap years exist is because the Earth's orbit is slightly out of sync with our usual annual calculations. The rotation of the Earth around the sun takes 365 days, 5 hours, 48 minutes and 46 seconds. To make up for this extra 5 hours of time, there is another leap day every four years in February. This concept can be traced back to the ancient Romans and was perfected in the Gregorian calendar introduced by Pope Gregory XIII in 1582. Although the purpose of this day is to align our year with the solar calendar, it can also serve as an additional day to prepare for spring.
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