主题：【原创】明清火器的迷思 -- 恶魔之读书者

haab 是356天，18月20天。 至于润月， 哈布历根本没有置闰

这样，每一年的时令节气都会和上一年产生一点偏差。日积月累之下

玛雅人注意到了这种这种偏差。在玛雅古文献中有这样的描述：每过29个“历法循环”（Calendar Round，是指“卓尔金年”和“哈布年”按最小公倍数形成的循环。一个历法循环是52个哈布年，29个历法循环就是1508个哈布年），实际上是过了1507年 。按这个描述来计算的话，玛雅人认为一年是365.242203天（365×1508÷1507=365.242203），这确实比格里高利历的每年365.2425天更接近太阳年的真正长度：365.242189天 。

玛雅人用了400多年观察了金星运转，还有很精确的金星历的。

再贴一个wiki吧，

Maya astronomy refers to the studies of the stars, planets, sun, and other astronomical occurrences by the Precolumbian Maya Civilization of Mesoamerica. The Classic Maya in particular saw the Maya develop some of the most accurate pre-telescope astronomy in the world, aided by their fully developed writing system and their positional numeral system, both of which are fully indigenous to Mesoamerica. The Classic Maya understood of many astronomical phenomena: For example, their estimate of the length of the synodic month being more accurate than Ptolemy's,[2] and their calculation as to the length of the tropical solar year was more accurate than that of the Spanish when the latter first arrived.[3]

玛雅数字的体系既有其特色，也有其适用性与科学性。在世界各古代文明中，除了起源于印度的阿拉伯数字之外，玛雅数字要算是最先进的了。