Latitude and azimuth determination were crucial for Polynesian navigators, supplemented by techniques such as observations of swells, birds and expanded landfalls. Longitude could only be determined by dead reckoning. Both latitude and azimuth made extensive use of stars, which alter gradually over the centuries due to precession, the movement in the Earth's axis of spin. Knowledge about the effects of precession can assist scholars in weighting one voyaging date higher than another, or in providing possible reasons why certain voyages took place in a particular era if navigation methods depended on star configurations that were particularly favourable in that era. The influence of precession on stars used for different methods of latitude determination is not intuitive. In this article a graph of the change in declination per century as a function of right ascension is proposed as a way of understanding the influence of precession on different methods of latitude and azimuth determination, and of deducing when and where significant configurations occur.

中文翻译：

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波利尼西亚考古天文学中的岁差问题

纬度和方位角确定对于波利尼西亚航海者至关重要，辅之以诸如观察海浪，飞鸟和扩大的登陆区等技术。经度只能通过推算来确定。纬度和方位角都大量使用了恒星，由于进动（地球自转轴的运动）在几个世纪中逐渐改变。关于进动的影响的知识可以帮助学者权衡一个航行日期比另一个航行日期高的权重，或者如果导航方法依赖于那个时代特别有利的星型，则可以提供在特定时代发生某些航行的可能原因。进动对用于不同纬度确定方法的恒星的影响并不直观。